4. Systematic code examples: a guided tour of Transcrypt

One ready-to-run code example is worth more than ten lengthy descriptions. The autotest and demo suite, that is part of the distribution, is a collection of sourcecode fragments called testlets. These testlets are used for automated regression testing of Transcrypt against CPython. Since they systematically cover all language constructs, they are also very effective as a learning tool. The testlets are arranged alphabetically by subject.

Autotest: Transcrypt autotest demo suite
from org.transcrypt.stubs.browser import __pragma__
import org.transcrypt.autotester

import arguments
import attribs_by_name
import builtin_super
import byte_arrays
import callable_test
import classes
import complex_numbers
import conditional_expressions
import control_structures
import dashed_numbers
import data_classes
import data_structures
import decorators
import dict_comprehensions
import dictionaries
import div_issues
import div_pulls
import docstrings
import exceptions
import executable_comments
import extended_slices
import fstrings
import general_functions
import globals_function
import indices_and_slices
import iterators_and_generators
import lambda_functions
import list_comprehensions
import local_classes
import metaclasses
import method_and_class_decorators
import module_builtin
import module_cmath

if __pragma__ ('defined', 'undefined'):
    import module_collections

import module_datetime
import module_itertools
import module_math
import module_unicodedata
import modules
import nonlocals
import operator_overloading
import properties
import proxies
import reprtest
import set_comprehensions
import simple_and_augmented_assignment

if __pragma__ ('defined', '__sform__'):
    import string_format

import truthyness
import tuple_assignment

autoTester = org.transcrypt.autotester.AutoTester ()
autoTester.run (arguments, 'arguments')
autoTester.run (attribs_by_name, 'attribs_by_name')
autoTester.run (builtin_super, 'builtin_super')
autoTester.run (byte_arrays, 'byte_arrays')
autoTester.run (callable_test, 'callable')
autoTester.run (classes, 'classes')
autoTester.run (complex_numbers, 'complex_numbers')
autoTester.run (conditional_expressions, 'conditional_expressions')
autoTester.run (control_structures, 'control_structures')
autoTester.run (dashed_numbers, 'dashed_numbers')
autoTester.run (data_classes, 'data_classes')
autoTester.run (data_structures, 'data_structures')
autoTester.run (decorators, 'decorators')
autoTester.run (dict_comprehensions, 'dict_comprehensions')
autoTester.run (dictionaries, 'dictionaries')
autoTester.run (div_issues, 'div_issues')
autoTester.run (div_pulls, 'div_pulls')
autoTester.run (docstrings, 'docstrings')
autoTester.run (exceptions, 'exceptions')
autoTester.run (executable_comments, 'executable_comments')
autoTester.run (extended_slices, 'extended_slices')
autoTester.run (fstrings, 'fstrings')
autoTester.run (general_functions, 'general_functions')
autoTester.run (globals_function, 'globals_function')
autoTester.run (indices_and_slices, 'indices_and_slices')
autoTester.run (iterators_and_generators, 'iterators_and_generators') 
autoTester.run (lambda_functions, 'lambda_functions')
autoTester.run (list_comprehensions, 'list_comprehensions')
autoTester.run (local_classes, 'local_classes')
autoTester.run (metaclasses, 'metaclasses')
autoTester.run (method_and_class_decorators, 'method_and_class_decorators')
autoTester.run (module_builtin, 'module_builtin')
autoTester.run (module_cmath, 'module_cmath')

if __pragma__ ('defined', 'undefined'):
    autoTester.run (module_collections, 'module_collections')

autoTester.run (module_datetime, 'module_datetime')
autoTester.run (module_itertools, 'module_itertools')
autoTester.run (module_math, 'module_math')
autoTester.run (module_unicodedata, 'module_unicodedata')
autoTester.run (modules, 'modules')
autoTester.run (nonlocals, 'nonlocals')
autoTester.run (operator_overloading, 'operator_overloading')
autoTester.run (properties, 'properties')
autoTester.run (reprtest, 'repr_str')
autoTester.run (proxies, 'proxies')
autoTester.run (set_comprehensions, 'set_comprehensions')
autoTester.run (simple_and_augmented_assignment, 'simple_and_augmented_assignment')

if __pragma__ ('defined', '__sform__'):
    autoTester.run (string_format, 'string_format')
 
autoTester.run (truthyness, 'truthyness')
autoTester.run (tuple_assignment, 'tuple_assignment')

autoTester.done ()

4.1. Arguments: **kwargs, *args, defaults, at call and def time, also for lambda’s

Testlet: arguments
from org.transcrypt.stubs.browser import __pragma__

__pragma__ ('kwargs')

class A:
    def __init__ (self, x = 123, y = 456, *args, m, n = 456, **kwargs):
        self.x = x
        self.y = y
        self.args = args
        self.m = m
        self.n = n
        self.kwargs = kwargs
        self.extra = 'hello'

    def f (self, autoTester):
        autoTester.check (self.x, self.y, self.args, self.m, self.n, self.kwargs, self.extra)
        
class B (A):
    def __init__ (self, x, y = -1, *args, m = -2, n, **kwargs):
        A.__init__ (self, y, x, *args, m = n, n = m, **kwargs)
        
class C:
    __pragma__ ('nokwargs')
    def tricky (self, *args):
        return args
    __pragma__ ('kwargs')
    
def run (autoTester):
    def f (x, y = -1, *args, m = -2, n, **kwargs):
        # BEGIN issue 203, kwargs turned into real dict
        autoTester.check ('#203', kwargs.__class__.__name__)
        autoTester.check ('#203', sorted (kwargs.keys ()))
        # END issue 203
    
        def f2 (x, y = -3, *args, m = -4, n, **kwargs):
            autoTester.check (x, y, args, m, n, kwargs)
        f2 (11, 22, 1010, 2020, m = 100100, n = 200200, p = 10001000, q = 20002000)
        autoTester.check (x, y, args, m, n, kwargs)
        
    f (1, 2, 10, 20, m = 100, n = 200, p = 1000, q = 2000)
    
    b = B (3, 4, 30, 40, m = 300, n = 400, p = 3000, q = 4000)
    b.f (autoTester)
    
    def g (*args, **kwargs):
        autoTester.check (args, kwargs)
        
    g (*(1, 2, 3), **{'p': 'aP', 'q': 'aQ', 'r': 'anR'})
    
    (lambda x, y = -1, *args, m = -2, n, **kwargs: autoTester.check (x, y, args, m, n, kwargs)) (1, 2, 8, 16, m = 128, n = 256.3, p = 1024.3, q = 2048.3)
    
    autoTester.check (C () .tricky (* range (4)))
    autoTester.check ('{}-{}'.format (1, 3, 5, 7, 9))
    autoTester.check ('{}-{}'.format (* range (4)))

4.2. Attribute access by name: getattr, setattr, hasattr

Testlet: attribs_by_name
class A:
    def __init__ (self):
        self.s = 'hello'
        
a = A ()

def run (autoTester):
    autoTester.check (a.s, getattr (a, 's'))
    
    setattr (a, 's', 'goodbye')
    autoTester.check (a.s, getattr (a, 's'))
    
    setattr (a, 't', 'exists')
    autoTester.check (hasattr (a, 't'), a.t, getattr (a, 't'))
    
    delattr (a, 't')
    autoTester.check (hasattr (a, 't'))

4.3. Attribute proxies by name: __getattr__, __setattr__

Testlet: proxies
from org.transcrypt.stubs.browser import __pragma__

def run (autoTester):
    class CodedStore:
        def __init__ (self):
            try:
                __pragma__ ('js', '{}', 'self ["__dict__"] = {}')
            except:
                pass

        def __setattr__ (self, name, message):
            self.__dict__ ['_' + name] = 'coded_' + message

        def __getattr__ (self, name):
            return 'decoded_' + self.__dict__ ['_' + name]
            
        def peek (self, name):
            return self.__dict__ ['_' + name]
            
    s = CodedStore ()

    s.john = 'brown'
    s.mary = 'white'

    autoTester.check (s.peek ('john'))
    autoTester.check (s.peek ('mary'))

    autoTester.check (s.john)
    autoTester.check (s.mary)
    
    '''
    The code above produces the following output:
        'coded_brown'
        'coded_white'
        'decoded_coded_brown'
        'decoded_coded_white'
    '''

    class A:
        def __init__ (self):
            self.p = 1
            self.q = 2
            
    class B (A):
        def __getattr__ (self, name):
            return 'Faked {}'.format (name)
            
    class C (A):
        def __setattr__ (self, name, value):
            autoTester.check ('Set faked {}'.format (name))
            
            A.__setattr__ (self, name, value)
            # Needed for CPython, inherited from class 'object'
            # Transcrypt doesn't need it, if there's no __setattrib__ it will just use self [name] = value
    
    class D (B, C):
        pass
        
    a = A ()
    b = B ()
    c = C ()
    d = D ()
    
    autoTester.check (a.p, a.q)
    a.p = 3
    autoTester.check (a.p, a.q)
    
    autoTester.check (b.p, b.q, b.r, b.s)
    b.p = 4
    b.r = 5
    autoTester.check (b.p, b.q, b.r, b.s)
    
    autoTester.check (c.p, c.q)
    c.p = 6
    c.q = 7
    autoTester.check (c.p, c.q)

    autoTester.check (d.p, d.q, d.r, d.s)
    d.p = 8
    d.q = 9
    d.r = 10
    d.s = 11
    autoTester.check (d.p, d.q, d.r, d.s)  

    # Issue 587, code as utilized by pjbonestro

    autoTester.check ("Issue 587")

    class Element():
        def __init__(self):
            self.message = "Goodbye"

        def sayBye(self):
            autoTester.check (self.message)

    class Wrapper():
        def __init__ (self, element):
            self.element = element

        def __setattr__ (self, name, value):
            """ set attribute on element if it already has the attribute """
            if name != "element" and hasattr(self.element, name):
                setattr(self.element, name, value)
            else:
                self.__dict__[name] = value

        def __getattr__ (self, name):
            """ get attribute from element if this object doesn't have the attribute """
            result = getattr(self.element, name)
            # if result is a function, bind self.element to it
            if hasattr(result, 'call') and hasattr(result, 'bind'):
                result = result.bind(self.element)
            return result

        def sayHello(self):
            autoTester.check("Hello")
            return self


    e = Element()
    w = Wrapper(e)

    #
    # Usage
    #

    e.sayBye()
    w.sayBye() # call functions on e, using w

    # and method chaining should work:
    w.sayHello().sayBye()  
    
    w.message = "Bye" # set attributes on e, using w
    
    e.sayBye()
    w.sayBye() # call functions on e, using w

    # and method chaining should work:
    w.sayHello().sayBye()  
    
    autoTester.check ("End issue 587")

    # End of issue 587
    

4.4. Bytes and bytearrays: initial support

Testlet: byte_arrays
def run (autoTester):
    b = b'bike'
    s = bytes ('shop', 'utf8')
    e = b''
    bb = bytearray ([0, 1, 2, 3, 4])
    bc = bytes ((5, 6, 7, 8, 9))

    # __pragma__ ('opov')
    bps = b + b'pump' + s
    bps3 = 3 * bps + b'\0'
    aBps3 = bps * 3 + b'\0'
    l = [1, 2, 3] + [4, 5, 6]
    # __pragma__ ('noopov')

    def formatCheck (aBytes):
        autoTester.check ([int (aByte) for aByte in aBytes])
    
    formatCheck (b)
    formatCheck (s)
    formatCheck (e)
    formatCheck (bb)
    formatCheck (bc)
    formatCheck (bps)
    formatCheck (bps3)
    formatCheck (aBps3)

    # __pragma__ ('opov')
    formatCheck (bb + bc)
    formatCheck (bytearray ('ding', 'utf8') + b'dang' + bytes ('dong', 'utf8'))
    # __pragma__ ('noopov')

    formatCheck (l)

4.5. Callable or not: using the callable () built-in function

The callable (object) built-in function will tell you if something supports the () operator.

Testlet: callable_test
# Callable built-in method unit tests

from org.transcrypt.stubs.browser import __pragma__

def run(test):
    """
    """

    def func(a,b):
        return(a*b)

    test.check( func(3,4) )
    test.check( callable(func) )

    for a in (True, False):
        test.check( callable(a) )

    a = 1
    test.check( callable(a) )
    a = 2.3
    test.check( callable(a) )
    a = "asdf"
    test.check( callable(a) )

    a = []
    test.check( callable(a) )
    a = [1,2,3,3]
    test.check( callable(a) )
    a = ["asdf", "qwer", "zxcv"]
    test.check( callable(a) )

    a = {"asdf" : 1, "qwer": 2}
    test.check( callable(a) )

    a = set([1,2])
    test.check(callable(a))

    __pragma__('opov')

    class CallObj(object):
        def __init__(self, r):
            self._r = r

        def __call__(self):
            return(self._r)

    test.check( callable(CallObj) )

    obj = CallObj(2)
    test.check(obj())
    test.check( callable(obj) )
    test.check( callable(obj._r) )

    class NonCallObj(object):
        def __init__(self, b):
            self._b = b

        def func(self):
            return(self._b)

    test.check( callable(NonCallObj) )

    obj2 = NonCallObj(2)
    test.check( callable(obj2) )
    test.check( callable(obj2._b) )
    test.check( callable(obj2.func) )

    __pragma__('noopov')

    class NonOpovNonCallObj(object):
        """
        """
        def __init__(self, c):
            self._c = c

        def other(self, b):
            return(self._c * b)

        def _getC(self):
            return(self._c)
        def _setC(self, val):
            self._c = val

        C = property(_getC, _setC)

    obj = NonOpovNonCallObj(4)
    test.check( callable(obj) )
    test.check( callable(obj.other) )
    test.check( callable(obj._c) )
    test.check( callable(obj.C) )

    exc = Exception("asdf")
    test.check( callable(exc) )

4.6. Classes: multiple inheritance and assignment of bound functions

Testlet: classes
def run (autoTester):
    autoTester.check ('<br>General<br>')

    class A:
        p = 123
        def __init__ (self, x):
            self.x = x
            autoTester.check (self.p)

        def show (self, label):
            autoTester.check ('A.show', label, self.x)
            
        def show2 (self, label):
            autoTester.check ('A.show2', label, self.x)
        
    class B:
        p, q = 456, 789
        def __init__ (self, y):
            autoTester.check ('In B constructor')
            self.y = y
            autoTester.check (self.p)
            
        def show (self, label):
            autoTester.check ('B.show', label, self.y)
            
    class C (A, B):
        def __init__ (self, x, y):
            autoTester.check ('In C constructor')
            A.__init__ (self, x)
            B.__init__ (self, y)
            
        def show (self, label):
            A.show (self, label)
            B.show (self, label)
            autoTester.check ('C.show', label, self.x, self.y)
        
    a = A (1001)
    a.show ('america')
    autoTester.check (A.p)
    autoTester.check (a.p)

    b = B (2002)
    b.show ('russia')
    autoTester.check (B.p)
    autoTester.check (b.p)
    autoTester.check (b.q)

    autoTester.check (A.p)
    autoTester.check (a.p)

    c = C (3003, 4004)
    c.show ('netherlands')
    autoTester.check (C.p)
    autoTester.check (c.p)
    autoTester.check (c.q)

    c.show2 ('amsterdam')
    A.show2 (c, 'rotterdam')

    show3 = c.show
    show3 ('copy')
    
    autoTester.check (hasattr (a, 'x'))
    autoTester.check (hasattr (a, 'y'))
    autoTester.check (hasattr (a, 'p'))
    autoTester.check (hasattr (a, 'q'))
    
    autoTester.check ('<br><br>Augmented isinstance and issubclass<br>')
    # Augmented meaning: compatible with native JavaScript types
        
    simpleTypes = (dict, list, A, B, C, bool, str, float, int, object)
    tupleTypes = ((dict, list), (bool, int), (bool, A), (C, B), (B, object))
    for i, types in enumerate ((simpleTypes, tupleTypes)):
        for j, aType in enumerate (types):
            for k, anObject in enumerate (({'a': 1}, [], a, C, c, C, b, True, 'a', 1, 1.2)):
                autoTester.check (i, j, k, isinstance (anObject, aType))
                if types == simpleTypes:
                    autoTester.check (i, j, k, isinstance (anObject, simpleTypes))

    for i, types in enumerate ((simpleTypes, tupleTypes)):
        for j, aType in enumerate (types):
            for k, aClass in enumerate ((dict, list, A, C, B, bool, str, int, float)):
                autoTester.check (i + 2, j, k, issubclass (aClass, aType))
                if types == simpleTypes:
                    autoTester.check (i + 2, j, k, issubclass (aClass, simpleTypes))
                    
    autoTester.check ('<br><br>Method resolution order<br>')
    
    def mro (aClass, result = None):
        ''' Recursively assemble method resolution order from all base classes'''
        last = 0
        if result is None:
            result = [aClass]
            last = 1
        for aBase in aClass.__bases__:
            if not aBase in result and aBase != object:
                result.append (aBase)
                mro (aBase, result)
        if last and object in aClass.__bases__:
            aRoot.append (object)
        return result
        
    autoTester.check ([aClass.__name__ for aClass in mro (C)])
    

4.7. Complex numbers: Python’s builtin complex datatype

Testlet: complex_numbers
from org.transcrypt.stubs.browser import __pragma__

def run (autoTester):
    x = 567
    y = -3
    z = 5 * x + 2 * y
    autoTester.check (x.conjugate () .real, x.conjugate () .imag)
    autoTester.check (x, y, z)

    __pragma__ ('opov')
    
    a = 234 + 3j
    b = 4 - 5j
    c = complex (-6, 7)
    d = 1
    autoTester.check (a, b, c)
    autoTester.check (d.conjugate () .real, d.conjugate () .imag)
    
    t = 6 * x - 3 * y + 7   # Just to check, faster with 'noopov'
    autoTester.check (t)
    
    d = 2 * a
    e = x * b
    f = z + d + e
    g = a / b
    h = a - b
    i = x - c
    j = a - x
    k = b + y
    
    autoTester.check (d, e, f, round (g.real, 2), round (g.imag, 2), h, i, j, k)
    
    __pragma__ ('noopov')
    

4.8. Conditional expressions: simple and nested

Testlet: conditional_expressions
def f (x, b):
    return x * x if b else x + x

def run (autoTester):
    bools = (False, True)
    for a in bools:
        for b in bools:
            autoTester.check (f (10 if a else 100, b))
            
    for p in bools:
        for q in bools:
            for r in bools:
                autoTester.check ('a' if p else 'b' if q else 'c' if r else 'd')
                
                a = ((('e' if p else 'f') if q else 'g') if r else 'h')
                b = ('i' if p else ('j' if q else ('k' if r else 'l')))
                c = 'm' if (p if q else r) else 'n'
                d = 'o' if p < q <= r else 'p'
                autoTester.check (a, b, c, d)
                
    odd = [x if x % 2 else x + 1 for x in range (10)]
    noDuplicates = set (odd)
    autoTester.check (odd, noDuplicates)
    

4.9. Control structures: for…else, while…else, if…elif…else, break, continue

Testlet: control_structures
class ContextManagerExample:
    def __init__ (self):
        self.counter = 0
        
    def __enter__ (self):
        self.counter += 1
        return self
        
    def __exit__ (self, *args):
        self.counter += 99

def run (autoTester):

    # General control structure tests

    for index in range (10):
        autoTester.check (index)
        
    for index in range (8, 16):
        autoTester.check (index)
        
    for index in range (8, 16, 2):
        autoTester.check (index)
        
    for index in range (10, 0, -1):
        autoTester.check (index)
        
    for index in range (16, 8, -2):
        autoTester.check (index)
        
    for animal in ('cat', 'dog', 'turtle', 'goldfish'):
        autoTester.check (animal)

    for index, square in enumerate ([x * x for x in range (10) if x % 2]):
        for y in (1, 2, 3):
            for z in (10, 20, 30):
                autoTester.check (square + y, z )

    vehicles = ['bike', 'train', 'boat', 'car', 'plane', 'bus']
                
    for doBreak in (False, True):
        for doContinue in (False, True):
            for index in range (10):
                for index2 in range (0, 100, 10):
                    if doBreak and index2 == 50:
                        autoTester.check ('break2')
                        break
                    if doContinue and index2 == 50:
                        autoTester.check ('continue2')
                        continue
                else:
                    autoTester.check ('noBreak2')
                    
                if doBreak and index == 5:
                    autoTester.check ('break')
                    break
                if doContinue and index == 5:
                    autoTester.check ('continue')
                    continue
            else:
                autoTester.check ('noBreak')
                
            index = 0
            while index < len (vehicles) and vehicles [index] != 'bus':
                autoTester.check (index, vehicles [index])
                if doBreak and vehicles [index] == 'car':
                    autoTester.check ('breakWhile')
                    break
                if doContinue and vehicles [index] == 'car':
                    autoTester.check ('continueWhile')
                    index += 1
                    continue
                index += 1
            else:
                autoTester.check ('noBreakWhile')
                
        for vehicle in vehicles:
            if vehicle == 'bike':
                autoTester.check ('netherlands')
            elif vehicle == 'car':
                autoTester.check ('america')
            elif vehicle == 'boat':
                autoTester.check ('oceania')
            else:
                autoTester.check ('anywhere') 
                
    # Context manager tests

    externalCounter1 = 0
    with ContextManagerExample () as contextManagerExample1:
        externalCounter1 += 1
    autoTester.check ('ctx1', contextManagerExample1.counter, externalCounter1)
    
    externalCounter2 = 0
    with ContextManagerExample () as contextManagerExample2:
        externalCounter2 += 1
        contextManagerExample2.counter += 100
        externalCounter3 = 0
        with ContextManagerExample () as contextManagerExample3:
            externalCounter3 += 1
            contextManagerExample2.counter += 100     
            externalCounter3 += 2
            contextManagerExample3.counter += 200
        autoTester.check ('ctx3', contextManagerExample3.counter, externalCounter3)
        externalCounter2 += 2
        contextManagerExample2.counter += 200
    autoTester.check ('ctx2', contextManagerExample2.counter, externalCounter2)

    try:
        externalCounter4 = 0
        with ContextManagerExample () as contextManagerExample4:
            externalCounter4 += 1
            contextManagerExample4.counter += 100
            externalCounter5 = 0
            with ContextManagerExample () as contextManagerExample5:
                externalCounter5 += 1
                contextManagerExample5.counter += 100
                raise Exception ()    
                externalCounter5 += 2
                contextManagerExample5.counter += 200  
            externalCounter4 += 2
            contextManagerExample4.counter += 200
    except Exception as exception:
        autoTester.check ('ctx6', exception)
    finally:
        autoTester.check ('ctx5', contextManagerExample5.counter, externalCounter5)
        autoTester.check ('ctx4', contextManagerExample4.counter, externalCounter4)

    # Multiple context managers in one clause
    
    # $$$ The new parsers seems to treat them more like separate context managers.
    # $$$ Or maybe it's a command line switch.
    
    
    iterationCount = 0
    with ContextManagerExample () as contextManagerExample5, ContextManagerExample () as contextManagerExample6:
        iterationCount += 1
    autoTester.check ('ctx7', iterationCount, contextManagerExample5.counter, contextManagerExample6.counter)

    iterationCount = 0
    with ContextManagerExample (), ContextManagerExample (), ContextManagerExample (), \
         ContextManagerExample (), ContextManagerExample ():
        iterationCount += 1
    autoTester.check ('ctx8', iterationCount)

4.10. Data classes: Avoiding boilerplate code

Testlet: data_classes
from dataclasses import dataclass
from typing import ClassVar

def getQ ():
    return 1002

@dataclass
class A:
    m = 101010
    n: int = 202020

@dataclass
class B (A):
    p: int = 1001
    q: int = 1002
    
@dataclass (order = True)
class C (B):
    @dataclass
    class CC (B):
        k: int = 40
        l: float = 55.5
        j = 60
    x: ClassVar = 10
    y: int = 20
    yy: int = 22
    z: int = 30
    zz: int = 33
    t: ClassVar = 40
    g = 100000
    h = 100001
    i = 100002
    
    def getV (self):
        return 3
        
    def setV (self, value):
        pass
    
    v = property (getV, setV)

    def getW (self):
        return 4
        
    def setW (self, value):
        pass
    
    w: int = property (getW, setW)

    def f (self, p, autoTester):
        self.a = p
        self.b = 2000
        autoTester.check (self.x, self.y, self.a)
        return f'something(a: {self.a}, b: {self.b})'


@dataclass (order = True)        
class D:        
    _p: int = 3

    def setP (self, value):
        pass
        #self._p = value

    def getP (self):
        return 20
        #return self._p
        
    p: int = property (getP, setP)
    
def run (autoTester):
    c = C (y = 200, zz = 330)
    cc = C (y = 10200)
    c.f (123, autoTester)
    c.t = 400
    cc.f (456, autoTester)
    cc.t = 4000
    
    for obj in c, cc:
        autoTester.check (obj.x, obj.y, obj.yy, obj.z, obj.zz, obj.t, obj.a, obj.b)
        
    autoTester.check (repr (c))
    autoTester.check (repr (cc)) 
    
    #__pragma__ ('opov')
    
    autoTester.check (c == cc)
    autoTester.check (c != cc)
    
    autoTester.check (c < cc)
    autoTester.check (c > cc)  #
    autoTester.check (c <= cc) #
    autoTester.check (c >= cc)
    
    autoTester.check (c == c)
    autoTester.check (c != c)
    autoTester.check (c < c)
    autoTester.check (c > c)
    autoTester.check (c <= c)
    autoTester.check (c >= c)

    d3 = D ()
    d1 = D ()
    d2 = D ()
    
    autoTester.check (repr (d1))

    autoTester.check (d3, d1, d3 > d1)
    autoTester.check (d2, d1, d2 > d1)
    autoTester.check (d3, d2, d3 > d2) 

    ccc = C.CC ()
    autoTester.check (ccc.n, ccc.p, ccc.q, ccc.k, ccc.l)
    

4.11. Data structures: tuple, list, dict, set

Testlet: data_structures
def run (autoTester):
    aList = [1, 2, 3, 'moon', 'stars']
    autoTester.check (aList)
    aList.insert (3, 'sun')
    autoTester.check (aList)
    autoTester.check (aList [2:4:1])
    autoTester.check (aList [:])
    autoTester.check (aList [2:])
    autoTester.check (len (aList))
    aList.append ('milkyway')
    autoTester.check (aList)
    aList.extend (['m1', 'm31'])
    autoTester.check (aList)

    anotherList = list (('a', 'b', 'c'))
    autoTester.check (anotherList)
    autoTester.check ('b' in anotherList)
    autoTester.check ('d' in anotherList)
    
    aDict = {1: 'plant', 'animal': 2}
    autoTester.check (aDict)
    autoTester.check (aDict [1], aDict ['animal'])
    
    def p ():
        return 3
        
    q = 4
    
    autoTester.check ({p (): 'three', q: 'four'})
    
    aTuple = (1, 2, 3, 4, 5)
    autoTester.check(aTuple)
    autoTester.check (len (aTuple))

    anotherTuple = (1,)
    autoTester.check (anotherTuple)

    aSet = {1, 2, 2, 3}
    autoTester.check (aSet)
    autoTester.check (len (aSet))
    autoTester.check (2 in aSet)
    autoTester.check (4 in aSet)
    aSet.clear ()
    autoTester.check (aSet)

    anotherSet = set ((4, 5, 5, 6))
    autoTester.check (anotherSet)

    emptySet = set ()
    autoTester.check (emptySet)
    autoTester.check (len (emptySet))
    
    aString = 'c_cis_d_dis_e_f_fis_g_gis_a_ais_b_c'
    autoTester.check ('cis' in aString)
    autoTester.check ('g' in aString)
    autoTester.check ('bes'  in aString)
    autoTester.check ('z' in aString)
    

4.12. Decorators: function and class, with and without parameters

Transcrypt supports decorators on methods and classes. A decorator itself can be a function or an object with an overloaded __call__ operator. Parameterized decorator factories are also supported. All flavours of properties can be used directly or through decorator syntax. Extensive use of properties is demonstrated in the properties testlet.

Testlet: decorators
from org.transcrypt.stubs.browser import __pragma__

def run (autoTester):
    def repeat3 (bareFunc):
        __pragma__ ('kwargs')
        def innerFunc (*args, **kwargs):
            autoTester.check ('BEGIN repeat3')
            for i in range (3):
                bareFunc (*args, **kwargs)
            autoTester.check ('END repeat3')
        __pragma__ ('nokwargs')
        return innerFunc
        
    def repeatN (n):
        def repeat (bareFunc):
            __pragma__ ('kwargs')
            def innerFunc (*args, **kwargs):
                autoTester.check ('BEGIN repeatN ({})'.format (n))
                for i in range (n):
                    bareFunc (*args, **kwargs)
                autoTester.check ('END repeatN ({})'.format (n))
            __pragma__ ('nokwargs')
            return innerFunc
        return repeat

    class Repeater:
        def __init__ (self, n):
            self.n = n
            
        def __call__ (self, bareFunc):
            __pragma__ ('kwargs')
            def innerFunc (*args, **kwargs):
                autoTester.check ('BEGIN repeat3')
                for i in range (self.n):
                    bareFunc (*args, **kwargs)
                autoTester.check ('END repeat3')
            __pragma__ ('nokwargs')
            return innerFunc
        
    @repeatN (4)
    @repeat3
    def funcNoArg ():
        autoTester.check ('spam')
        
    funcNoArg ()
    autoTester.check ()

    __pragma__ ('kwargs')
    @repeat3
    @repeatN (2)
    def funcArg (a):
        autoTester.check ('eggs', a)
    __pragma__ ('nokwargs')
        
    funcArg (3)
    autoTester.check ()

    funcArg (a = 4)
    autoTester.check ()

    __pragma__ ('opov')
    @Repeater (3)
    def funcNoArg2 ():
        autoTester.check ('toast')
    __pragma__ ('noopov')

    funcNoArg2 ()
    autoTester.check ()

    __pragma__ ('opov')
    __pragma__ ('kwargs')
    @Repeater (5)
    def funcArg2 (a):
        autoTester.check ('jam', a)
    __pragma__ ('nokwargs')
    __pragma__ ('noopov')

    funcArg2 (3)
    autoTester.check ()

    funcArg2 (a = 4)
    autoTester.check ()

    def next (bareFunc):
        def innerFunc (value):
            return bareFunc (value + 1)
        return innerFunc
        
    @next
    class Number:
        def __init__ (self, value):
            self.value = value
            
    autoTester.check ('two', Number (1) .value)
    
    class Test: 
        @classmethod
        def f (cls, x, y):
            autoTester.check (cls.__name__, x, y)
            
        def g (self, x, y):
            autoTester.check (self.__class__.__name__, x, y)
            
    test = Test ()

    test.f (1, 2)
    test.g (3, 4)
    
    

4.13. Dict comprehensions

Testlet: dict_comprehensions
from org.transcrypt.stubs.browser import __pragma__

__pragma__ ('iconv')    # Convert dict to key list without using keys () method

def run (autoTester):
    original = {'Isaac': 'Newton', 'Albert': 'Einstein', 'Paul': 'Dirac'}
    autoTester.check (original)

    inverted = {original [key]: key for key in original}
    autoTester.check (inverted)

4.14. Dictionaries: dict revisited

Testlet: dictionaries
from org.transcrypt.stubs.browser import __pragma__
__pragma__ ('iconv')

# Dictionaries are translated to JavaScript objects,
# to achieve JSON-compatible syntax for JavaScript library object initialisation.
# Keys that may denote a number are interpreted as such in Transcrypt.
# All other keys are interpreted as strings.

def run (autoTester):
    tel = {'guido': 4127, 'jack': 4098}
    autoTester.check (len (tel))
    tel ['sape'] = 4139

    autoTester.check (tel)
    autoTester.check (tel ['jack'])

    del tel ['sape']
    tel ['irv'] = 4127
    autoTester.check (tel)

    autoTester.check (sorted (list (tel.keys ())), False)
    autoTester.check (sorted (tel.keys ()))

    autoTester.check ('guido' in tel)
    autoTester.check ('jack' not in tel)

    autoTester.check (dict ([('guido', 4127), ('jack', 4098), ('sape', 4139)]))
    autoTester.check (
        autoTester.expectException( lambda: dict(1) )
    )
    autoTester.check (
        autoTester.expectException( lambda: dict(134.34) )
    )
    autoTester.check (
        autoTester.expectException( lambda: dict('asdf') )
    )
    autoTester.check (
        autoTester.expectException( lambda: dict(['1234', 1]) )
    )

    autoTester.check( dict ([]))
    autoTester.check (dict ({}))
    autoTester.check (dict ({'asdf': 1, 'qwer': 2}) )

    # check dict copy, Issue # 221
    b = {'a' : 2.01, 'b': -3.3}
    d = dict (b)
    autoTester.check (d)
    b = {'a' : 2, 'b': [1,2,3]}
    d = dict (b)
    autoTester.check (d)
    b = {'a' : None, 'b': set([1,2,3])}
    d = dict (b)
    autoTester.check (d)
    b = {'a' : {'c': 2}, 'b': (1,2)}
    d = dict (b)
    autoTester.check (d)
    autoTester.check (d['a']['c'])
    autoTester.check (d.get('a').get('c'))
    autoTester.check (b.get('a').get('c'))
    d['a']['c'] = 3
    autoTester.check (d.get('a').get('c'))
    autoTester.check (b.get('a').get('c'))

    knights = {'robin': 'the brave', 'gallahad': 'the pure'}

    for k, v in sorted (knights.items ()):
        autoTester.check (k, v)

    if 'gallahad' in knights:
        autoTester.check ('gallahad is a knight') 

    for k in sorted (knights):
        autoTester.check (k)
        
    knight = {'rudolph': 'the righteous'}
    for k in knight:    # Autotest automatic conversion with one knight, since sort order of dict undefined
        autoTester.check (k)
        
    tel = {'guido': 123}
    tel.update({'edsger': 42})
    autoTester.check (tel.setdefault ('linus', 456))
    autoTester.check (tel ['linus'])
    autoTester.check (tel.setdefault ('guido', 789))
    autoTester.check (tel.pop ('guido', 1))
    autoTester.check (tel.pop ('guido', 1))
    autoTester.check (tel.pop ('edsger', 2))
    autoTester.check (tel.pop ('foo', 'bar'))
    autoTester.check (tel.pop ('foo', None))

    # Check compound keys (issue 281)
    
    d = {}
    d ['a'] = 3777
    d [(1, 2)] = 4777
    autoTester.check (d ['a'], d [(1, 2)])

    __pragma__ ('opov')
    d = {}
    d ['a'] = 3777
    d [(1, 2)] = 4777
    autoTester.check (d ['a'], d [(1, 2)])
    __pragma__ ('noopov')
    
    # Check exceptions
    knights = {'robin': 'the brave', 'gallahad': 'the pure'}
    autoTester.check (
        autoTester.expectException ( lambda: knights.pop("batman") )
    )
    autoTester.check (
        autoTester.expectException ( lambda: knights.pop("batman", None) )
    )
    autoTester.check (
        autoTester.expectException ( lambda: knights.pop("batman", "the gullible") )
    )

4.15. Diverse issues

Testlet: div_issues
from org.transcrypt.stubs.browser import __pragma__, __new__, __envir__, __symbols__

from div_issues.issue55 import *        # Names not exported from package's __init__.py, no output, only compilation check
from div_issues.issue387 import run387  # Support __module__ and __qualname__ for introspection (only __module__ done and
                                        # __name__ set to '__main__ for main module'
from div_issues.issue559 import run559  # Imported names not reexported form the __init__.py of a module

import re
                           
def run (autoTester):
    autoTester.check ('Issue 24')   # Non keyword switch generates javascript SyntaxError
    switch = False
    autoTester.check (switch)
    
    autoTester.check ('Issue 27')   # Python list.index () not translated correctly
    autoTester.check (['zero', 'one', 'two', 'three', 'four'] .index ('three'))
    
    autoTester.check ('Issue 36')   # Bug in compiling lambda default argument values
    # Workaround for Python closures capturing variables rather than values
    # An extra enclosing scope is created to remember the value of the variable
    results = []
    for i in range (10):
        # results.append (lambda: i)                # Works nowhere
        # results.append (lambda j = i: j)          # Works only in Python
        results.append ((lambda j: lambda: j) (i))  # Works in Python and Transcrypt
    autoTester.check ([result () for result in results])        

    autoTester.check ('Issue 37')   # Python integer division not translated correctly
    autoTester.check (15 // 7)
    
    autoTester.check ('Issue 40')   # Python parentheses dropped during translation
    autoTester.check (65 / (5 * 2))

    autoTester.check ('Issue 50')   # Wrong answer with parentheses moved during translation
    autoTester.check ((240 + 30 - 1) // 30 * 30)
    
    autoTester.check ('Issue 51')   # Wrong answer with set() compare
    a = 1
    b = 1
    autoTester.check (a, b, {a, b} == {1, 2})
    
    autoTester.check ('Issue 52')   # Non keyword 'default' generates javascript SyntaxError
    switch, case, default = 'switch', 'case', 'default'
    autoTester.check (switch, case, default)
    
    autoTester.check ('Issue 54')   # Type dict missing clear(), setdefault()
    aDict = {1: 11, 2: 22, 3: 33}
    autoTester.check (aDict)
    aDict.clear ()
    autoTester.check (aDict)
    
    autoTester.check ('Issue 60')   # Python bool() not translated
    three = 3
    one = three & 1
    seven = three | 4
    eight = one << 3
    four = eight >> 1
    aTrue = bool (three & one)
    aFalse = bool (three & four)
    autoTester.check (3, three, 1, one, 7, seven, 8, eight, 4, four, True, aTrue, False, aFalse)
    
    autoTester.check ('Issue 65')   # Adding two lists with + not supported
    __pragma__ ('opov')
    aList = [4, 5, 6]
    autoTester.check ([1, 2, 3,] + aList + [4, 5, 6])
    autoTester.check (3 * [1, 2, 3])
    autoTester.check ([1, 2, 3] * 3)
    aString = 'Crocodile'
    autoTester.check ('Tiger' + aString + 'Elephant')
    autoTester.check (3 * aString)
    autoTester.check (aString * 3)
    __pragma__ ('noopov')
    
    autoTester.check ('Issue 76')   # Python //= not translated correctly
    initially17 = 17
    autoTester.check (initially17)
    initially17 //= 2
    autoTester.check (initially17)
    initially17 //= 2
    autoTester.check (initially17)
    
    autoTester.check ('Issue 112')  # When using -e6, iterating TypedArrays or other non-list Iterables doesn't work
    try:
        if __envir__.executor_name == __envir__.transpiler_name: # CPython doesn't know Int8Array
            x = __new__ (Int8Array (2))
        else:
            x = [None, None]
        
        x [0] = 3
        x [1] = 2
        for i in x:
            autoTester.check (i)
        
        y = 3
        for j in y:
            autoTester.check (j)
            
    except: # No 'Exception' can be used behind this, since this is a JavaScript exception, and no subclass of Exception. ??? How desirable is this behaviour?
        pass
        # autoTester.check ('Detected iterating over non-iterable') # Minifier masks this exception, so we'll have to pass
        
    autoTester.check ('Issue 122')  # Problem with yield (or rather with slicing beyond list end)
    
    def chunks (aList, chunkLength):
        for index in range (0, len (aList), chunkLength):
            yield aList [index : index + chunkLength]

    for chunk in chunks ([chr (index + 97) for index in range (26)], 10):
        autoTester.check (chunk)

    autoTester.check ('Issue 123')  # Python % shouldn't behave like JS %
    autoTester.check (10 % 3, 10 % -3, -10 % 3, -10 % -3, 10 % 10, 10 % -10, -10 % 10, -10 % -10)
    
    autoTester.check ('Issue 125')  # Strings not iterable
    abc = 'abc'
    
    for index in abc:
        autoTester.check (abc)
        
    autoTester.check ('Issue 127')  # Can't use the key 'keys' in a dict
    autoTester.check ({"include_docs": "true", "keys": ["key1", "key2"], "limit": 50})
    
    autoTester.check ('Issue 134')  # Operator %= translated incorrectly
    x0, x1, x2, x3, x4, x5 = 5, 12, -5, -5, 0, 0
    x0 %= 10; x1 %= 5; x2 %= 2; x3 %= -3; x4 %= 1; x5 %= -1000 
    autoTester.check (x0, x1, x2, x3, x4)
    
    autoTester.check ('Issue 136')  # Method dict.get(key[, default]) not implemented
    aDict = {'a': 'ape', 'b': 'banana'}
    autoTester.check (aDict.get ('a', 'noApe'), aDict.get ('b'), aDict.get ('c', 'noCarot'), aDict.get ('d'))
    
    autoTester.check ('Issue 144')
    __pragma__('opov')
    aList = [x for x in [1, 2, 3]]
    autoTester.check (aList)
    __pragma__('noopov')    
    
    autoTester.check ('<br><br>Issue 145<br>')  # List sorting incorrect in case of multiple columns
    
    class SortTest:
        def __init__ (self):
            self.alphabet = 'abcdefghijklmnopqrstuvwxyz'
            self.nChars = 10
            self.nCols = 10
            self.nRows = 30
            
            self.pseudoRandom = 0
            
            def randomWord ():
                word = ''
                for iChar in range (self.nChars):
                    self.pseudoRandom = (81212 * self.pseudoRandom + 28411) % 134456
#                   self.pseudoRandom = (1234 * self.pseudoRandom + 57) % 137           # Deliberately short period
                    word += self.alphabet [self.pseudoRandom % 26]
                return word 
        
            self.rows = [[randomWord () for iCol in range (self.nCols)] for iRow in range (self.nRows)]
                
        def sort (self):
            for iCol in reversed (range (self.nCols)):
                self.rows.sort (key = lambda row: row [iCol])
            
    sortTest = SortTest ()
    
    autoTester.check ('<br>Unsorted:<br>')
    for row in sortTest.rows:
        autoTester.check ('{}<br>'.format (','.join ([word for word in row])))
        
    sortTest.sort ()
    
    autoTester.check ('<br>Sorted:<br>')
    for row in sortTest.rows:
        autoTester.check ('{}<br>'.format (','.join ([word for word in row])))
        
    autoTester.check ('<br><br>Issue 148<br>')  # Allow key a.o. key 'items' in dict
    
    aDict = {
        'items': [4, 5, 6]
    }

    for aKey, aValue in aDict.items ():
        autoTester.check ('{}: {}'.format (aKey, aValue))   
        
    autoTester.check ('<br><br>Issue 169<br>')  # Add support for float('inf') and float('-inf')
    
    autoTester.check (int (1 / float ('inf')), int (1 / float ('-inf')))
    
    autoTester.check ('<br><br>Issue 178<br>')  # List Comprehensions / Operator Precedence Bug
    
    bitmaps = [
        (2 , ''),
        (4 , ''),
        (8, 'i'),
        (16, 'm'),
        (32, 'y'),
        (64, 'u'),
        (128, 'g')
    ]
    
    for flags in (122, 233, 11, 55, 79, 201, 23, 111, 200, 100, 50, 25, 12, 6):
        autoTester.check  (''.join ([x [1] for x in bitmaps if (x [0] & flags) > 0]))
        
    def issue256 ():
        autoTester.check ('Issue 256')

        class C:
            def __init__ (self, value):
                self.value = value

        def f1 (value):  # Generate parens after return
            return (C (value) .value or 'second') .capitalize () == 'First'
            
        def f2 (value):  # Generate parens after return
            return (C (value) .value or 'second') .capitalize () == 'Second'
            
        def f3 (value):  # Generate NO parens after return
            return C (value) .value or 'second'
            
        def f4 (value):  # Generate NO parens after return
            return (C (value) .value or 'second')
                
        autoTester.check (f1 ('first'))
        autoTester.check (f1 (''))
        autoTester.check (f2 ('first'))
        autoTester.check (f2 (''))
        autoTester.check (f3 ('first'))
        autoTester.check (f4 (''))
        
    issue256 ()
    
    autoTester.check ('Issue 274')
    a = 3
    del a
    autoTester.check ('Still alive')

    autoTester.check ('Issue 276')  # Partial, other part tested in testlet 'operator_overloading'
    a = 2
    b = a ** 3
    a **= 4
    autoTester.check (a, b)
        
    autoTester.check ('Issue 277')
    new = 3
    autoTester.check (new)
    
    autoTester.check ('Issue 279')
    class A:
        TypeError = 111
        js_TypeError = 222
    autoTester.check (A.TypeError, A.js_TypeError)  # ... Generated code should use py_TypeError and TypeError respectively    
    autoTester.check ('Still alive')
    
    autoTester.check ('Issue 301')
    def filter_word (word0, word1):
        if len (word0) != len (word1):
            return False
        for char0, char1 in zip (word0, word1):
            if char0 != '_' and char0 != char1:
                return False
        return True
    autoTester.check (filter_word ('bee', 'beer'))
    autoTester.check (filter_word ('wine', 'wine'))
    autoTester.check (filter_word ('win_', 'wind'))
    autoTester.check (filter_word ('_in_', 'kind'))
    autoTester.check (filter_word ('min_', 'kind'))

    autoTester.check ('Issue 306')
    dict_306 = {'Abraham': 'Lincoln', 'Barack': 'O\'Bama', 'Thomas': 'Jefferson'}
    results = []
    try:
        while True:
            results.append (dict_306.popitem ())
    except Exception as exception:
        autoTester.check (sorted (results))
        autoTester.check ('That\'s it')

    autoTester.check ('Issue 314')
    try:
        autoTester.check (int (float (123)))
    except:
        autoTester.check ('a')
        
    try:
        autoTester.check (float (12.3))
    except:
        autoTester.check ('b')
        
    try:
        autoTester.check (int (float ('123')))
    except:
        autoTester.check ('c')
        
    try:
        autoTester.check (int (float (' 123')))
    except:
        autoTester.check ('d')
                        
    try:
        autoTester.check (float (''))
    except:
        autoTester.check ('e')
        
    try:
        autoTester.check (float (' '))
    except:
        autoTester.check ('f')
    try:
        autoTester.check (float ('drie'))
    except:
        autoTester.check ('g')
        
    autoTester.check ('Issue 316')
    
    autoTester.check (list (filter (None, [[1, 2], [3], [], [4, 5], [6]])))
    autoTester.check (list (filter (lambda l: len (l) >= 2, [[1, 2], [3], [], [4, 5], [6]])))
    
    autoTester.check ('Issue 317')

    mylist = []
    try:
        mylist.remove ('value')
    except ValueError as exception:
        autoTester.check (exception.__class__.__name__)
        
    autoTester.check ('Issue 331')
    
    autoTester.check (max (-5, 4, 1, 2, -3, 2))
    autoTester.check (max ([-5, 4, 1, 2, -3, 2]))
    autoTester.check (max ((5, 6, 2, -2, -4)))

    autoTester.check (min (-5, 4, 1, 2, -3, 2))
    autoTester.check (min ([-5, 4, 1, 2, -3, 2]))
    autoTester.check (min ((5, 6, 2, -2, -4)))
    
    autoTester.check ('issue 356')
    
    try:
        raise TypeError("How are you?")
    except TypeError as exception:
        autoTester.check (exception)
        
    autoTester.check ('Issue 369')
    
    class Vector:
        def __init__ (self, *values):
            self.values = values

        def __iter__ (self):
            for item in self.values:
                yield item

        def __add__(self, other):
            return Vector (* (x + y for x, y in zip (self, other)))
            
        def __str__ (self):
            return str (list (self.values))
        
    #__pragma__ ('opov')

    autoTester.check (str (Vector (1,2,3) + Vector (3,4,5)))

    #__pragma__ ('noopov')

    
    autoTester.check ('Issue 387')
    run387 (autoTester)
    
    autoTester.check ('Issue 391')
    autoTester.check (int (False))
    autoTester.check (int (True))
    autoTester.check (int (1 == 2))
    autoTester.check (int (1 != 2))
    
    autoTester.check ('Issue 392')

    class Example:

        d = {'A': 1, 'B': 2}
        rec = re.compile ('(?P<decimal>\d+)', re.ASCII)

        def run(self):
            match = self.rec.match ('42')
            if not match:
                print('ERROR: RE does not match')
            e = match.groupdict ()
            autoTester.check ("before: self.d=", self.d)
            autoTester.check ("before: e=", e)
            self.d.update (e)
            autoTester.check ("after: self.d=", self.d)


    example = Example ()
    example.run ()
    
    autoTester.check ('Issue 398')
    # This used to give extra comma's so invalid syntax (no check calls needed)
    
    class Test398 (object):
        #__pragma__ ('skip')
        def method1 (self):
            pass

        def method2 (self):
            pass
        #__pragma__ ('noskip')
        pass
        
    test398 = Test398 ()
        
    autoTester.check ('Issue 399')
    
    __pragma__ ('keycheck')
    try:
        surpressWarning = {'a':5}['a']
        surpressWarning = {'a':5}['b']
        autoTester.check ('no problem')
    except KeyError:
        autoTester.check ('not found')    
    
    autoTester.check ('Issue 413')
    __pragma__ ('nokeycheck')
    
    class Foo:
        def __len__ (self):
            return 3
        
        def __getitem__ (self, i):
            if i >= 3:
                raise IndexError
            return 'This is item ' + str (i)

    foo = Foo ()

    #__pragma__ ('opov')
    autoTester.check ('Attempt 1:')
    for i in foo:
        autoTester.check (i)

    autoTester.check ('Attempt 2:')
    for i in range (len (foo)):
        autoTester.check (foo [i])
    #__pragma__('noopov')
    
    autoTester.check ('Issue 414')
    
    class Foo:
        pass

    foo = Foo ()
    foo.bar = 'baz'
    foo.name = 'hello'
    foo.default = 'world'

    autoTester.check ([x for x in dir (foo) if not x.startswith ('__')])

    #__pragma__('kwargs')
    def foo (*args, **kwargs):
        default = kwargs.get ('default', 'bar')
        return default

    autoTester.check (foo())
    autoTester.check (foo(default = 'Hello World'))
    
    autoTester.check ('Issue 460')
    
    s460 = 'car'
    l460 = [11, 22, 33]
    t460 = (4, 5, 6)
    d460 = {-1: 'mmminusOne', 'b': 'bbbike'}
    
    #__pragma__ ('opov')
    
    l460 [0] = 1
    l460 [-2] = 2
    l460 [-1] = 3
    
    d460 [-1] = 'minusOne'
    d460 ['b'] = 'bike'
    
    autoTester.check (s460 [0], s460 [1], s460 [2], s460 [-1], s460 [-2], s460 [-3])
    autoTester.check (l460 [0], l460 [1], l460 [2], l460 [-1], l460 [-2], l460 [-3])
    autoTester.check (t460 [0], t460 [1], t460 [2], t460 [-1], t460 [-2], t460 [-3])
    autoTester.check (d460 [-1], d460 ['b'])
    
    autoTester.check (s460 [0], s460 [1], s460 [2], s460 [-1], s460 [-2], s460 [-3])
    autoTester.check (l460 [0], l460 [1], l460 [2], l460 [-1], l460 [-2], l460 [-3])
    autoTester.check (t460 [0], t460 [1], t460 [2], t460 [-1], t460 [-2], t460 [-3])
    autoTester.check (d460 [-1], d460 ['b'])

    #__pragma__ ('noopov')

    #__pragma__ ('keycheck')
    
    try:
        autoTester.check (d460 [-1], d460 ['c'])
    except:
        autoTester.check (111)
    try:
        autoTester.check (d460 [-2], d460 ['b'])
    except:
        autoTester.check (222)
        
    #__pragma__ ('nokeycheck')
    
    a = [1, 2, 3]
    b = [4, 5, 6]
    c = '1,2,34,5,6'

    if __envir__.executor_name == __envir__.transpiler_name:
        autoTester.check (a + b)
        autoTester.check (a + b)    #__:opov
        autoTester.check (a + b)
    else:
        autoTester.check (c)
        autoTester.check (a + b)    #__:opov
        autoTester.check (c)

    #__pragma__ ('opov')
        
    if __envir__.executor_name == __envir__.transpiler_name:
        autoTester.check (a + b)    #__:noopov
        autoTester.check (a + b)
        autoTester.check (a + b)    #__:noopov
    else:
        autoTester.check (c)        #__:noopov
        autoTester.check (a + b)
        autoTester.check (c)        #__:noopov

    #__pragma__ ('noopov')
    
    autoTester.check ('Issue 494')  # {None} in formatted string gets converted to {}
    
    # Worked, should still work
    a = 1
    autoTester.check (f'a={a}')

    # Failed, should now work
    a = None
    autoTester.check (f'a={a}')
    
    autoTester.check ('Issue 515')  # Method format() is failing to replace the replacement fields if the value is None
    
    autoTester.check('a: {}; b: {}'.format(None, 1))
    autoTester.check('a: {}; b: {}'.format(1, None))
    autoTester.check('a: {0}; b: {1}'.format(1, None))
    autoTester.check('a: {0}; b: {1}'.format(1, []))
    autoTester.check('a: {}; b: {}'.format(1, []))
    autoTester.check('a: {0}; b: {1}'.format(1, {}))
    autoTester.check('a: {}; b: {}'.format(1, {}))
    autoTester.check('a: {0}; b: {1}'.format(1, 0))
    autoTester.check('a: {}; b: {}'.format(1, 0))
    
    autoTester.check ('Issue 559')  # Reexport everything imported, e.g. by the __init__.py of a module
    run559 (autoTester)
    

4.16. Diverse pulls

Testlet: div_pulls
# Also contains small enhancements

import div_pulls.pull575_reexport_modules as pull575

'This is a single line docstring'
class A:
    '''
    This
    is 
    a 
    multiline
    docstring
    '''
    def __init__ (self, x):
        'This is a single line comment'
        self.x = x
        '''
        This
        is 
        a 
        multiline
        docstring
        '''
    'This is a single line docstring'
'''
This
is 
a 
multiline
docstring
'''

a = A (5.5)

def run (autoTester):   
    autoTester.check ('Pull 56')
    s = 'abcdefghij'
    autoTester.check (s [2:3])
    autoTester.check (s [:3])
    autoTester.check (s [2:])
    autoTester.check (s [::2])
    
    autoTester.check ('Pull 59')
    autoTester.check (list (filter (lambda x: x % 2 == 0, range (10))))
    autoTester.check (list (map (lambda x: x*x, range (0, 31, 3))))
    
    autoTester.check ('Pull 561')
    def brackets (word):
        autoTester.check ('sideeffect')
        return '[' + word + ']'
    autoTester.check (brackets ('anything') .lower ())   #__:opov
    
    pull575.run (autoTester)
    

4.17. Docstrings: __doc__ attribute generated optionally

To keep the generated code lean, generation of __doc__ attributes is controlled per module by __pragma__ (‘docat’) or by the -d / –docat command line switch, combined with user per module of __pragma__ (‘nodocat’)

Testlet: docstrings
'''Just a module
to test docstrings'''
'''Not visible'''

from org.transcrypt.stubs.browser import __pragma__
__pragma__ ('docat')

def run (autoTester):
    def f (p):
        '''Just a function
        called f'''
        '''Not visible'''
        autoTester.check (p) 

    class C:
        '''Just a class
        called C'''
        '''Not visible'''
        def g (self, q):
            '''Just a method
            called g'''
            '''Not visible'''
            autoTester.check (q)
        
    autoTester.check (__doc__)
    autoTester.check ()

    autoTester.check (f.__doc__)
    autoTester.check ()

    autoTester.check (C.__doc__)
    autoTester.check ()

    autoTester.check (C.g.__doc__)
    autoTester.check ()

    f ('Doc')
    C () .g ('strings')

4.18. Exceptions: exception class hierarchy, finally

Testlet: exceptions
from org.transcrypt.stubs.browser import __envir__, __new__, __pragma__

class Ex1 (Exception):
    pass
        
class Ex2 (Ex1):
    pass
    
class Ex3 (Exception):
    pass
    
class Table (BaseException):    # Any Python exception MUST inherit from BaseException
    def __init__ (self, *args):
        self.fields = args
        
    def __repr__ (self):
        return 'Table' + repr (self.fields) .replace (', ', ',') .replace ('\'', '')

def test1 ():
    raise (Exception ('mary'))
    
def test2 (autoTester):
    try:
        test1 ()
    except Ex1 as exception:
        autoTester.check (111)
        autoTester.check (exception)
    except Exception as exception:
        autoTester.check (222)
        autoTester.check (exception)
        
def run (autoTester):
    test2 (autoTester)
    
    try:
        raise Ex2 ('had')
    except Ex1 as exception:
        autoTester.check ('a')
    except Exception as exception:
        autoTester.check ('little')
        autoTester.check (exception)
        
    autoTester.check (333)
        
    try:
        raise Ex1 ('lamb')
    except Ex2 as exception:
        autoTester.check ('his')
        autoTester.check (exception)
    except Ex1 as exception:
        autoTester.check ('fleece')
        autoTester.check (exception)
    except Exception as exception:
        autoTester.check ('was')
        autoTester.check (exception)
    finally:
        autoTester.check ('white')
        
    autoTester.check (444)

    def test3 ():
        raise Ex3 ('as')
        
    autoTester.check (555)

    try:
        test3 ()
    except Ex1 as exception:
        autoTester.check ('snow')
        autoTester.check (exception)
    except Exception as exception:
        autoTester.check ('and')
        autoTester.check (exception)
    finally:
        autoTester.check ('everywhere')
        
    autoTester.check (666)
    
    try:
        raise Ex3 ('that')
    except Ex1 as exception:
        autoTester.check ('mary')
        autoTester.check (exception)
    except:
        autoTester.check ('went')
    finally:
        autoTester.check ('the')
    
    autoTester.check (777)
    
    try:
        try:
            raise Ex3 ('lamb')
        except Ex1 as exception:
            autoTester.check ('was')
            autoTester.check (exception)
        finally:
            autoTester.check ('to')
    except Ex3 as exception:    # We should get here, exception not swallowed
        autoTester.check ('go')
        autoTester.check (exception)
        
    try:
        raise __new__ (Table ('he', 'followed', 'her'))
    except Ex1 as exception:
        autoTester.check ('to')
        autoTester.check (exception)
    except Table as exception:  # Pure JavaScript exception, if no Python __class__
        autoTester.check ('school')
        autoTester.check (exception)
    except Ex3 as exception:
        autoTester.check ('one')
        autoTester.check (exception)
    finally:
        autoTester.check ('day')
    
    try:
        assert 2 * 8 / 4 == 2, 'Assert error 1'
    except AssertionError as exception:
        autoTester.check (exception)
        
    try:
        assert 2 * 8 / 4 == 4, 'Assert error 2'
    except AssertionError as exception:
        autoTester.check (exception)
        
    try:
        assert 2 * 8 / 4 == 2
    except AssertionError as exception:
        autoTester.check (exception)
        
    try:
        assert 2 * 8 / 4 == 4
    except AssertionError as exception:
        autoTester.check (exception)
        
    autoTester.check (888)
    
    try:
        autoTester.check ('hello world 1')
    except:
        autoTester.check ('error 1')
    else:
        autoTester.check ('no error 1')
        
    i = 1 + 2
    try:
        autoTester.check ('hello world 2')
        if i == 3:  # Prevent unreachable code warning
            raise Exception ()
    except:
        autoTester.check ('error 2')
    else:
        autoTester.check ('no error 2')
        
    for raiseIt in (False, True):
        try:
            try:
                if raiseIt:
                    raise Exception ()
                autoTester.check ('no error 3')
            finally:
                autoTester.check ('anyhow 3')
        except:
            autoTester.check ('error 3')
            

4.19. Extended slices: facilitating NumScrypt and such

Testlet: extended_slices
from org.transcrypt.stubs.browser import *
from org.transcrypt.stubs.browser import __pragma__, __envir__

def indices (key):
    if __envir__.executor_name == __envir__.transpiler_name:
        return tuple (key) if type (key) == list else key
    else:
        try:
            return key.indices (1000000000)
        except:
            try:
                return tuple ([indices (subkey) for subkey in key])
            except:
                return key

class Test:
    def __init__ (self, autoTester):
        self.autoTester = autoTester

    def __getitem__ (self, key):
        self.autoTester.check ('getitem (', indices (key), ')')
        return 1234567
        
    def __setitem__ (self, key, value):
        self.autoTester.check ('setitem (', indices (key), ')', value)

def run (autoTester):
    a = b = c = d = e = f = g = h = i = j = k = l = Test (autoTester)

    __pragma__ ('opov')
            
    a [1:2:3, 4:5:6] = b [7:8:9]
    c [1:2:3] = d [4:5:6, 7:8:9]
    e [1, 1:2:3, 3] = f [4, 4:5:6, 6]
    g [1, 2, 3] = h [1, 2, 3]
    i [1] = j [1]
    k [1:2:3] = l [1:2:3]

4.20. General functions: sort and sorted

Testlet: general_functions
from org.transcrypt.stubs.browser import __pragma__

class A:
    foo='bar'
    def __init__ (self):
        self.foo2 = 'bar2'

class B (A):
    foo3='bar3'
    def __init__ (self):
        self.foo4 = 'bar4'
        
class C:
    def __len__ (self):
        return 42

def run (autoTester):
    autoTester.check ('len')

    strings = ['hello', ',', 'world', '!']
    instances = [C()]
    collections = [
        [], [1], [1, 2],
        tuple(), (1,), (1, 2),
        {}, {1: 1}, {1: 1, 2: 2}
    ]

    for string in strings:
        autoTester.check (len (string))

    for instance in instances:
        autoTester.check (len (instance))

    for collection in collections:
        autoTester.check (len (collection))

    autoTester.check ('sort and sorted<br>')
    a = [1, 5, 3, 2, -1]
    b = ['sun', 'earth', 'moon']
    
    autoTester.check (sorted (a))
    autoTester.check (sorted (b))
    
    a.sort ()
    autoTester.check (a)
    
    b.sort ()
    autoTester.check (b)

    autoTester.check (sorted (a, reverse = True))
    autoTester.check (sorted (b, reverse = True))
    
    a.sort (reverse = True)
    autoTester.check (a)
    
    b.sort (reverse = True)
    autoTester.check (b)
    
    b.sort (key = lambda x: len (x)) 
    autoTester.check (b)

    b.sort (key = lambda x: len (x), reverse = True) 
    autoTester.check (b)

    autoTester.check ('<br><br>dir<br>')
    autoTester.check ([entry for entry in dir (A) if not entry.startswith ('__')])
    autoTester.check ([entry for entry in dir (A()) if not entry.startswith ('__')])
    autoTester.check ([entry for entry in dir (B) if not entry.startswith ('__')])
    autoTester.check ([entry for entry in dir (B()) if not entry.startswith ('__')])

    autoTester.check ('<br><br>any, all, sum<br>')
    list1 = ['ape', 'node', 'mice']
    list2 = ['vim', '', 'jet']
    list3 = ['', '', '']
    list4 = [[1, 2], [1], []]   # Truthyness into play
    autoTester.check (list1, any (list1), all (list1))
    autoTester.check (list2, any (list2), all (list2))
    autoTester.check (list3, any (list3), all (list3))
    autoTester.check (list4, any (list4), all (list4))
    
    autoTester.check (sum (range (5)))
      
    def generator1 ():
        for i in range (5):
            yield i;
            
    def generator2 ():
        for i in range (5):
            if i % 2:
                yield 0
            else:
                yield i;
                
    def generator3 ():
        for i in range (5):
            yield 0;
                
        autoTester.check (generator1 (), any (generator1 ()), all (generator1 ()))
        autoTester.check (generator2 (), any (generator2 ()), all (generator2 ()))
        autoTester.check (generator3 (), any (generator3 ()), all (generator3 ()))
        
        autoTester.check (sum (generator1 ()))
    __pragma__ ('endif')

4.21. Global variable access by using globals () [<variable_name>]

The globals () function does the same as its counterpart in CPython, with some restrictions.

In the same module:

  • globals () can retrieve all module-level variables, whether created via globals () or in the normal way

  • module-level variables created via globals () can only be retrieved by globals (), not as a normal variable

From a different module:

  • globals () can retrieve all module-level variables, whether created by globals () or in the normal way

  • module-level variables created by globals () can be retrieved by globals (), but also as a normal variable

Since imports are done (statically) at compile time, from … import * will not include the variables created (dynamically) via globals (). You can however import the whole module, e.g. import <longName> as <shortName> and then use <shortName>.<dynamicallyCreatedVariable>.

The code below shows what’s possible:

Testlet: globals_function, module sub
#  __pragma__ ('xglobs')

xxa = 'subXxa'
xxb = 'subXxb'
xxp = None
xxq = None
xxr = None
xxs = None

for name in ('xxp', 'xxq'):
    globals () [name] = 'sub{}'.format (name.capitalize ())

def f ():
    for name in ('xxr', 'xxs'):
        globals () [name] = 'sub{}'.format (name.capitalize ())
        
def run (autoTester):
    f ()
    autoTester.check ('Check sub 1', xxa, xxb)    
    autoTester.check ('Check sub 2', * [globals () [name] for name in ('xxa', 'xxb', 'xxp', 'xxq', 'xxr', 'xxs')])
    autoTester.check ('Check sub 3', * sorted ([value for key, value in globals () .items () if key.startswith ('xx')]))

    
Testlet: globals_function, main program
# __pragma__ ('xglobs')

from globals_function import sub

xxa = 'mainXxa'
xxb = 'mainXxb'
xxp = None
xxq = None
xxr = None
xxs = None

for name in ('xxp', 'xxq'):
    globals () [name] = 'main{}'.format (name.capitalize ())    
    
def f ():
    for name in ('xxr', 'xxs'):
        globals () [name] = 'main{}'.format (name.capitalize ())
        
def run (autoTester):
    f ()                 # All vars of main added
    sub.run (autoTester) # Shouldn't override vars of main
    
    autoTester.check ('Check main 1', xxa, xxb)
    autoTester.check ('Check main 2', * [globals () [name] for name in ('xxa', 'xxb', 'xxp', 'xxq', 'xxr', 'xxs')])
    autoTester.check ('Check main 3', sub.xxa, sub.xxb, sub.xxp, sub.xxq, sub.xxr, sub.xxs)
    autoTester.check ('Check main 4', * sorted ([value for key, value in globals () .items () if key.startswith ('xx')]))
    

The output will be:

Output of 'global_functions autotest'

4.22. Indices and slices: LHS, RHS, basic and extended

Testlet: indices_and_slices
def run (autoTester):
    # Right hand side slices
    all = range (32)
    autoTester.check (all)
    
    autoTester.check (all [8 : 24])
    autoTester.check (all [8 : 24 : 2]) 
    
    # Left hand side slices
    aList = [3, 4, 7, 8]
    autoTester.check (aList)
    
    aList [4 : 4] = [9, 10]
    autoTester.check (aList)
    
    aList [2 : 2] = [5, 6]
    autoTester.check (aList)
    
    aList [0 : 0] = [1, 2]
    autoTester.check (aList)
    
    aList [ : : 2] = [x + 0.001 for x in range (10) if x % 2]
    autoTester.check (aList)

4.23. Iterators and generators

Testlet: iterators_and_generators
from org.transcrypt.stubs.browser import __pragma__

class Iterable:
    def __init__ (self, i):
        self.aList = range (0, 50, i)

    def __iter__ (self):
        return Iterator (self) 
        
class Iterator:
    def __init__ (self, iterable):
        self.iterable = iterable
        self.index = -1
        
    def __next__ (self):    # Should be auto-wrapped in a next (self) by the compiler 
        self.index += 1
        
        if self.index > 5:
            raise StopIteration ()
            
        return self.iterable.aList [self.index]
            
    def __iter__ (self):
        return self
        
def exhaustableGenerator (i):
    for i in range (5):
        yield 2 * i

def run (autoTester):
    exhaustableGenExp = (a * a * a for a in [10, 20, 30])   # Currently still converted to iterator on list comprehension, must also be iterable
    # So becomes py_iter (aList).
    # List already has an __iter__ which it will return, it's a __PyIterator__
    # To that __PyIterator__, that will already have a __next__, py_iter first adds a next
    # So exhaustableGenExp is an iterator with a next and a __next__
    # If we call iter on that, py_iter is calle again py_iter, on an object with a next and a next __next__
    # For this reason py_iter needs a recursion prevention check

    iterables = [Iterable (7), exhaustableGenerator (5), [i * 3 for i in range (5)], exhaustableGenExp]

    for iterable in iterables:  
        autoTester.check ('[1]')
        iterator = iter (iterable)
        try:
            while True:
                autoTester.check (next (iterator))
        except Exception as exception:
            autoTester.check (exception.__class__.__name__)

        autoTester.check ('[2]')
        iterator = iter (iterable)
        try:
            while True:
                autoTester.check (next (iterator))
        except Exception as exception:
            autoTester.check (exception.__class__.__name__)
            
    for iterable in iterables:
        autoTester.check ('[3]')
        for n in iterable:
            autoTester.check (n)
            
        autoTester.check ('[4]')
        for n in iterable:
            autoTester.check (n)
            
    # BEGIN issue 196: for loop over iter (), runs OK but needs JavaScript 6. This should be clearly in the docs.
            
    a = 0
    vals = [1,2,3]
    ret = iter (vals)
    for m in ret:
        a += m
    autoTester.check (a)
     
    # END issue 196
                
    # BEGIN 1st example with 'send'
        
    __pragma__ ('gsend')

    def test0 ():
        r = 0
        while True:
            r = r + (yield r)

    gen0 = test0()
    next (gen0)
    autoTester.check (gen0.send (1))
    autoTester.check (gen0.send (2))

    def test1 ():
        r = 0
        while True:
            r = (yield r) + r

    gen1 = test1()
    next (gen1)
    autoTester.check (gen1.send (3))
    autoTester.check (gen1.send (4))
    
    # END 1st example with 'send'
    
    def subGenerator ():
        yield 27
        yield 37
        yield 47
    
    
    def mainGenerator ():
        yield 17
        yield from subGenerator ()
        yield 57
        
    autoTester.check (* [i for i in mainGenerator ()])
    
    def subCoroutine ():
        autoTester.check (38)
        yield
        autoTester.check (48)
        yield
        autoTester.check (58)
        yield
        autoTester.check (68)
    
    
    def mainCoroutine ():
        autoTester.check (18)
        yield
        autoTester.check (28)
        yield from subCoroutine ()
        autoTester.check (78)
        yield
        autoTester.check (88)
        
    m = mainCoroutine ()
    for i in range (5):
        m.send (None)
        

4.24. Lambda functions with all types of args

Testlet: lambda_functions
def run (autoTester):
    z = 1000
    autoTester.check ((lambda x, y: x + y + z) (111, 222))

    def f (list0, list1, aFunc):
        return [aFunc (*elem) for elem in zip (list0, list1)]

    x = f (range (10), range (0, 100, 10), lambda x, y: x + y + z)
    autoTester.check (x)
    
    autoTester.check (f (range (10, 20), range (100, 200, 10), lambda x, y: x * y + 100 * z))
    autoTester.check (f (range (10, 20), range (100, 200, 10), lambda *args: args [0] * args [1] + 100 * z))

4.25. List comprehensions: multi-loop and nested with multiple if’s

Testlet: list_comprehensions
def run (autoTester):
    squares = [i * i for i in range (10) if i % 2]
    autoTester.check (squares)
    
    tuples = [
        (x, y, z)
        for x in (100, 200, 300, 400, 500, 600, 700)
            for y in (10, 20, 30, 40, 50, 60, 70) if 20 < y  < 60
                for z in (1, 2, 3, 4, 5, 6, 7) if 200 < x < 600 if 2 < z < 6
    ]
    autoTester.check (tuples)
    
    tricky = [(2 * x, 3 * y) for x, y in ((10, 11), (20, 21))]
    autoTester.check (tricky)
    
    nested = [2 * x for x in [x * x for x in range (3)]]
    autoTester.check (nested)
    
    a = 100
    x = 5
    scopeTest = [x + a for x in range (5)]
    autoTester.check (x)
    autoTester.check (scopeTest)

4.26. Local classes: inside other classes and functions

Testlet: local_classes
def run (autoTester):       
    class A:
        class B:
            class C:
                def __init__ (self, x):
                    self.x = x
                    
                def tell (self):
                    autoTester.check (self.x)
                    autoTester.check (self.e)
                    
                # Limitation: no destructuring assignment inside nested classes
                e = 3
                
            def __init__ (self, x):
                self.x = x
                
            def tell (self):
                autoTester.check (self.x)
                autoTester.check (self.d)
                
            d = 2
                
        c = 1

        def __init__ (self, x):
            self.x = x
            
        def tell (self):
            autoTester.check (self.x)
            autoTester.check (self.c)
            
    def f (x):
        class G:
            class H:
                def __init__ (self, x):
                    self.x = x
                    
                def tell (self):
                    autoTester.check (self.x)
                    autoTester.check (self.i)
                    
                i = 5
        
            def __init__ (self, x):
                self.x = x
                
            def tell (self):
                autoTester.check (self.x)
                
            k = 4
            
        g = G (6)
        g.tell ()
        autoTester.check (g.k)
        
        h = G.H (7)
        h.tell ()
        autoTester.check (h.i)
        
        class P (A.B):
            pass
            
        p = P (7)
        p.tell ()
        autoTester.check (p.d)
                
    a = A (8)
    b = a.B (9)
    c = b.C (10)

    a.tell ()
    b.tell ()
    c.tell ()

    autoTester.check (a.c)
    autoTester.check (b.d)

    f (7)

4.27. Metaclasses: overriding type.__new__ in a descendant metaclass

Testlet: metaclasses
from org.transcrypt.stubs.browser import __pragma__

class UppercaserMeta (type):
    def __new__ (meta, name, bases, attribs):
        __pragma__ ('jsiter')       # Translate for ... in directly to JavaScript for ... in ... and translate {} to bare {} rather than to dict {}
                                    # Using bare {} as attribs parameter to __new__ avoids dict attributes masking regular attributes
                                    # For more flexibility use __pragma__ ('js', '{}', '''...''')
        upperAttribs = {}
        
        for attribKey in attribs:   # Translates to 'for (var attribKey in attribs)' by virtue of __pragma__ ('jsiter'), to iterate over the attributes of a bare JavaScript {}
            upperAttribs [attribKey if  attribKey.startswith ('__') else attribKey.upper ()] = attribs [attribKey]
            
        __pragma__ ('nojsiter')
            
        return type.__new__ (meta, name, bases, upperAttribs)

class Uppercaser (metaclass = UppercaserMeta):
    pass
    
class Animal (Uppercaser):
    class Thoughts:
        quantity = 7

    # Limitation: no destructuring assignment if metaclass has to alter attributes
    color = 'Brown'
    state = 'Moving'

    def move (self):
        return 'Move'

class Plant (Uppercaser):
    class Thoughts:
        quantity = 6

    color = 'Green'
    state = 'Growing'

    def grow (self):
        return 'Grow'
        
class Stone:
    class Thoughts:
        quantity = 5

    color = 'Gray'
    
    def be (self):
        return ('Being')

def run (autoTester):
    animal = Animal ()
    autoTester.check (animal.THOUGHTS.quantity, Animal.COLOR, animal.COLOR, animal.MOVE ())
    
    plant = Plant ()
    autoTester.check (plant.THOUGHTS.quantity, Plant.COLOR, plant.COLOR, plant.GROW ())
    
    stone = Stone ()
    autoTester.check (stone.Thoughts.quantity, Stone.color, stone.color, stone.be ())
    

4.28. Method and class decorators

Testlet: method_and_class_decorators
from org.transcrypt.stubs.browser import __pragma__

def run (autoTester):

    class adecorator:
        __pragma__('kwargs')
        def __init__(self, *args, **kwargs):
            self.args = args
            self.kwargs = kwargs
        __pragma__('nokwargs')

        def __call__(self, func):
            __pragma__('kwargs')
            def wrapper(*args, **kwargs):
                slf = args[0]

                # replace and store the attributes
                saved = {}
                for k, v in self.kwargs.items():
                    if hasattr(slf, k):
                        saved[k] = getattr(slf, k)
                        setattr(slf, k, v)

                # call the method
                ret = func(*args, **kwargs)

                # put things back
                for k, v in saved.items():
                    setattr(slf, k, v)

                return ret

            __pragma__('nokwargs')
            return wrapper

    def method_decorator(prefix):
        def inner_decorator(method):
            def wrapper(self, name):
                autoTester.check(name)
                return method(self, prefix + name)
            return wrapper
        return inner_decorator

    def method_decorator2(prefix):
        def inner_decorator(method):
            def wrapper(self, name):
                autoTester.check(name)
                return method(self, prefix + name)
            return wrapper
        return inner_decorator

    def multiplier(m):
        def inner_decorator(method):
            def wrapper(self, num):
                autoTester.check(num)
                n = method(self, num)
                return n * m
            return wrapper
        return inner_decorator

    def classmethod_decorator(method):

        def wrapper(cls, a, b):
            autoTester.check(cls.__name__, a, b)
            return method(cls, b, a)

        return wrapper

    def class_decorator(prefix):

        def wrapper(cls):
            autoTester.check(prefix + cls.__name__)
            return cls

        return wrapper

    @class_decorator('outer_')
    class MyClass:

        @class_decorator('inner_')
        class InnerClass:
            @method_decorator('inner_first_')
            @method_decorator2('inner_second_')
            def mymethod(self, name):
                autoTester.check(name)

            @classmethod
            @classmethod_decorator
            def myclassmethod(cls, a, b):
                autoTester.check(cls.__name__, a, b)
                return a + b

            @staticmethod
            def mystaticmethod(a, b):
                autoTester.check(a, b)
                return a + b

            @property
            def inner_property(self):
                return 'I am a property'

        def __init__(self):
            self.greetings = 'Hello'

        __pragma__('opov')
        @adecorator(greetings='Goodbye')
        def get_greetings(self):
            return self.greetings
        __pragma__('noopov')

        @method_decorator('first_')
        @method_decorator2('second_')
        def mymethod(self, name):
            autoTester.check(name)

        @multiplier(5)
        def number(self, num):
            return num

        @classmethod
        def myclassmethod(cls, a, b):
            autoTester.check(cls.__name__, a, b)
            return a + b

        @staticmethod
        def mystaticmethod(a, b):
            autoTester.check(a + b)
            return a + b

        @property
        def simple_property(self):
            return self.greetings

        @simple_property.setter
        def simple_property(self, value):
            self.greetings = value

        def run(self):
            inner_obj = self.InnerClass()
            inner_obj.mymethod('Dog')
            result1 = inner_obj.myclassmethod('param1', 'param2')
            result2 = self.InnerClass.myclassmethod('param1', 'param2')
            autoTester.check(result1 == result2)
            result1 = inner_obj.mystaticmethod('param1', 'param2')
            result2 = self.InnerClass.mystaticmethod('param1', 'param2')
            autoTester.check(result1 == result2)
            autoTester.check(inner_obj.inner_property)

    myobj = MyClass()
    myobj.mymethod('Cat')
    autoTester.check(myobj.greetings)
    autoTester.check(myobj.get_greetings())
    result1 = myobj.myclassmethod('param1', 'param2')
    result2 = MyClass.myclassmethod('param1', 'param2')
    autoTester.check(result1 == result2)
    result1 = myobj.mystaticmethod('param1', 'param2')
    result2 = MyClass.mystaticmethod('param1', 'param2')
    autoTester.check(result1 == result2)
    autoTester.check(myobj.number(3))
    autoTester.check(myobj.simple_property)
    myobj.simple_property = 'New value'
    autoTester.check(myobj.simple_property)
    autoTester.check(myobj.greetings == myobj.simple_property)
    myobj.run()

4.29. Module builtin: a small part of it demo’ed

Testlet: module_builtin
# coding: utf-8

from org.transcrypt.stubs.browser import __envir__

def canonizeString (aString):
    if __envir__.executor_name == 'transcrypt':
        return aString.replace ('\t', '\\t') .replace ('\n', '\\n')
    else:
        return aString

def canonizeStringList (stringList):
    return [canonizeString (aString) for aString in stringList]

def run (autoTester):
    autoTester.check ('min', min (-1.1, -1, -3))
    autoTester.check ('max', max (-1.1, -1, -3))
    autoTester.check ('abs', abs (-1), abs (1), abs (0), abs (-0.1), abs (0.1))
    autoTester.check ('ord', ord ('a'), ord ('e´'[0]))  # This is the 2 codepoint version
    
    autoTester.check ('round',
        round (4.006),
        round (4.006, 2),
        round (4060, -2),
        
        round (-4.006),
        round (-4.006, 2),
        round (-4060, -2),
        
        round (1/2.),
        round (1/2., 1),
        round (1/2, 1),
        round (1/3., 2),
        
        round (-1/2.),
        round (-1/2., 1),
        round (-1/2, 1),
        round (-1/3., 2),
    
        round (0.5),
        round (0.51),
        round (1.5),
        round (1.51),
        round (1.51),
        round (2.5),
        round (2.59),
        round (3.5),
        round (3.59),
        
        round (-0.5),
        round (-0.51),
        round (-1.5),
        round (-1.51),
        round (-1.51),
        round (-2.5),
        round (-2.59),
        round (-3.5),
        round (-3.59)
    )
    
    strings = [
        'der des dem den die der den die das des dem das',
        'an auf hinter ueber    neben vor   zwischen',
        '''
            durch
            fuer
            ohne
            um
            bis
            gegen
            entlang
        ''',
        'eins,zwei,drie,vier,fuenf,sechs,sieben'
    ]
    
    autoTester.check ('<br><br>split')
    for aString in strings:
        autoTester.check (
            canonizeString (aString),
            canonizeStringList (aString.split ()),
            canonizeStringList (aString.split (' ')),
            canonizeStringList (aString.split (' ', 4)),
            canonizeStringList (aString.split ('\t')),
            canonizeStringList (aString.split ('\t', 4)),
            canonizeStringList (aString.split ('\n')),
            canonizeStringList (aString.split ('\n', 4)),
            canonizeStringList (aString.split (',')),
            canonizeStringList (aString.split (',', 4)),
            '<br>'
        )
        
    autoTester.check ('<br>rsplit')
    for aString in strings:
        autoTester.check (
            canonizeString (aString),
            canonizeStringList (aString.rsplit ()),
            canonizeStringList (aString.rsplit (' ')),
            canonizeStringList (aString.rsplit (' ', 4)),
            canonizeStringList (aString.rsplit ('\t')),
            canonizeStringList (aString.rsplit ('\t', 4)),
            canonizeStringList (aString.rsplit ('\n')),
            canonizeStringList (aString.rsplit ('\n', 4)),
            canonizeStringList (aString.rsplit (',')),
            canonizeStringList (aString.rsplit (',', 4)),
            '<br>'
        )

    autoTester.check("".isalpha())
    autoTester.check("123".isalpha())
    autoTester.check("abc".isalpha())
    autoTester.check("abc123".isalpha())

    enumerate_list = ['a', 'b', 'c', 'd', 'e']
    # JS does not have tuples so coerce  to list of lists
    autoTester.check([list(item) for item in enumerate(enumerate_list)])
    autoTester.check([list(item) for item in enumerate(enumerate_list, 1)])
    autoTester.check([list(item) for item in enumerate(enumerate_list, start=2)])

    replace_test = "abcabcabcabc"
    autoTester.check(replace_test.replace("c", "x"))
    autoTester.check(replace_test.replace("c", "x", -1))
    autoTester.check(replace_test.replace("c", "x", 0))
    autoTester.check(replace_test.replace("c", "x", 1))
    autoTester.check(replace_test.replace("c", "x", 2))
    autoTester.check(replace_test.replace("c", "x", 10))

    autoTester.check(bin(42))
    autoTester.check(oct(42))
    autoTester.check(hex(42))
    autoTester.check(bin(0))
    autoTester.check(oct(0))
    autoTester.check(hex(0))
    autoTester.check(bin(-42))
    autoTester.check(oct(-42))
    autoTester.check(hex(-42))

    string_test = "abcdefghijkl"
    autoTester.check(string_test.startswith(""))
    autoTester.check(string_test.startswith("abcd"))
    autoTester.check(string_test.startswith("efgh"))
    autoTester.check(string_test.startswith("efgh", 2))
    autoTester.check(string_test.startswith("efgh", 4))
    autoTester.check(string_test.startswith("abcd", 0, 3))
    autoTester.check(string_test.startswith("abcd", 0, 5))
    autoTester.check(string_test.startswith("efgh", 4, -2))
    autoTester.check(string_test.startswith("efgh", 4, -6))
    autoTester.check(string_test.startswith(("abc",)))
    autoTester.check(string_test.startswith(("abc", "de", "gh")))
    autoTester.check(string_test.startswith(("abc", "de", "gh"), 2))
    autoTester.check(string_test.startswith(("abc", "de", "gh"), 3))
    autoTester.check(string_test.startswith(("abc", "defgh"), 3, 9))
    autoTester.check(string_test.startswith(("abc", "defgh"), 3, 6))

    autoTester.check(string_test.endswith(""))
    autoTester.check(string_test.endswith("ijkl"))
    autoTester.check(string_test.endswith("efgh"))
    autoTester.check(string_test.endswith("efgh", 2))
    autoTester.check(string_test.endswith("abcd", 0, 3))
    autoTester.check(string_test.endswith("abcd", 0, 4))
    autoTester.check(string_test.endswith("efgh", 4, -2))
    autoTester.check(string_test.endswith("efgh", 4, -4))
    autoTester.check(string_test.endswith(("ijkl",)))
    autoTester.check(string_test.endswith(("abc", "de", "gh")))
    autoTester.check(string_test.endswith(("abc", "de", "gh"), 3, -4))
    autoTester.check(string_test.endswith(("abc", "de", "gh"), -6, -4))
    autoTester.check(string_test.endswith(("abc", "defgh"), -3, 8))
    autoTester.check(string_test.endswith(("abc", "defgh"), -9, 8))

4.30. Module cmath: almost all of Python’s cmath module

Testlet: module_cmath
from org.transcrypt.stubs.browser import __pragma__
from cmath import *

twoPi = 2 * pi
nDecs = 5

__pragma__ ('opov')

def run (autoTester):
    autoTester.check (phase (1 + 1j))
    
    aPolar = polar (3 + 5j)
    autoTester.check (round (aPolar [0], nDecs), aPolar [1])
    
    aRect = rect (*aPolar)
    autoTester.check (round (aRect.real), round (aRect.imag))
    
    anExp = exp (-2.2 - 3.3j)
    autoTester.check (round (anExp.real, nDecs), round (anExp.imag, nDecs))
    
    aLog = log (anExp)
    autoTester.check (round (aLog.real, nDecs), round (aLog.imag, nDecs))
    
    anExp10 = aLog ** 10
    autoTester.check (round (anExp10.real, nDecs), round (anExp10.imag, nDecs))
    
    aLog10 = log10 (anExp10)
    autoTester.check (round (aLog10.real, nDecs), round (aLog10.imag, nDecs))
    
    anExpRect = aLog ** aRect
    autoTester.check (round (anExpRect.real, nDecs), round (anExpRect.imag, nDecs))
    
    aLogRect = log (anExpRect, aRect)
    autoTester.check (round (aLogRect.real, nDecs), round (aLogRect.imag, nDecs))
    
    aSqrt = sqrt (1j)
    autoTester.check (round (aSqrt.real, nDecs), round (aSqrt.imag, nDecs))
    autoTester.check (sqrt (4))
    anotherSqrt = sqrt (-4)
    autoTester.check (round (anotherSqrt.real), round (anotherSqrt.imag))
    
    anAsin = asin (1 + 2j)
    autoTester.check (round (anAsin.real, nDecs), round (anAsin.imag, nDecs))

    anAcos = acos (-2 + 3j)
    autoTester.check (round (anAcos.real, nDecs), round (anAcos.imag, nDecs))
    
    anAtan = atan (3 - 4j)
    autoTester.check (round (anAtan.real, nDecs), round (anAtan.imag, nDecs))
    
    aSin = sin (anAsin)
    autoTester.check (round (aSin.real), round (aSin.imag))
    
    aCos = cos (anAcos)
    autoTester.check (round (aCos.real), round (aCos.imag))
    
    aTan = tan (anAtan)
    autoTester.check (round (aTan.real), round (aTan.imag))
    
    anAsinh = asinh (aCos)
    autoTester.check (round (anAsinh.real, nDecs), round (anAsinh.imag, nDecs))

    anAcosh = acosh (aSin)
    autoTester.check (round (anAcosh.real, nDecs), round (anAcosh.imag, nDecs))
    
    anAtanh = atanh (aTan)
    autoTester.check (round (anAtanh.real, nDecs), round (anAtanh.imag, nDecs))
    
    aSinh = sinh (anAsinh)
    autoTester.check (round (aSinh.real), round (aSinh.imag))
    
    aCosh = cosh (anAcosh)
    autoTester.check (round (aCosh.real), round (aCosh.imag))
    
    aTanh = tanh (anAtanh)
    autoTester.check (round (aTanh.real), round (aTanh.imag))
    

4.31. Module datetime: transcryption of Python’s datetime module

Testlet: module_datetime
from datetime import date, timedelta, datetime, timezone

# __pragma__('opov')

def fix_time (dt):
    if dt.hour > 23:
        dt = dt - timedelta (minutes=60)
    if dt.minute > 50:
        dt = dt - timedelta (minutes=10)
    return dt

def run (autoTester):
    # timezone
    tz = timezone.utc
    autoTester.check (repr (tz))

    tz2 = timezone (timedelta (hours=-5), 'EST')
    autoTester.check (repr (tz2))

    now = fix_time (datetime.utcnow ())
    now2 = fix_time (datetime.now (timezone.utc))
    autoTester.check (now.day == now2.day)
    autoTester.check (now.hour == now2.hour)
    autoTester.check (now.replace (tzinfo=timezone.utc).astimezone (tz=None).hour)

    # timedelta
    delta = timedelta (days=8, minutes=15, microseconds=685)
    delta2 = timedelta (days=8, minutes=15, microseconds=684)
    autoTester.check (delta)
    autoTester.check (delta2)

    # timedelta comparisons
    autoTester.check (delta == delta2)
    autoTester.check (delta > delta2)
    autoTester.check (delta < delta2)

    # date
    d = date (2017, 5, 5)
    autoTester.check (d.day)
    d = date.today ()
    autoTester.check (d)
    autoTester.check (d.day)
    autoTester.check (d.weekday ())
    autoTester.check (d.isoweekday ())
    # !!! autoTester.check (d.isocalendar ()) Format changed in Python 3.9!
    # Autotest: module_datetime/__init__.py:45  datetime.IsoCalendarDate(year=2021, week=19, weekday=5) (2021, 19, 5)   module_datetime.js:108
    autoTester.check (d.ctime ())
    d = d.replace (day=28)
    autoTester.check (d.day)
    autoTester.check (d.strftime ('%Y.%m.%d'))
    autoTester.check (d.ctime ())
    autoTester.check (d.isoformat ())

    # date comparisons
    d2 = d + delta
    d3 = d2 - delta
    autoTester.check (d)
    autoTester.check (d2)
    autoTester.check (d3)
    autoTester.check (d == d3)
    autoTester.check (d > d3)
    autoTester.check (d < d3)
    autoTester.check (d == d2)
    autoTester.check (d > d2)
    autoTester.check (d < d2)

    # datetime
    now = fix_time (datetime.now ())
    autoTester.check (now.day)
    autoTester.check (now.hour)
    autoTester.check ((now + timedelta (days=2)).day)

    d = datetime (2010, 1, 1, tzinfo=timezone.utc)
    autoTester.check (d)

    d = datetime (2017, 9, 19, 15, 43, 8, 142)
    autoTester.check (d)
    autoTester.check (d - timedelta (minutes=150))

    d = datetime.strptime ('2017-03-14 15:28:14', '%Y-%m-%d %H:%M:%S')
    autoTester.check (d)
    autoTester.check (d.strftime ('%Y.%m.%d %H:%M:%S'))
    d = d + timedelta (hours=5, minutes=18, seconds=25)
    autoTester.check (d.strftime ('%Y-%m-%d %H:%M:%S'))
    d = d.replace (year=2016, month=1)
    autoTester.check (d.ctime ())
    autoTester.check (d.isoformat ())
    autoTester.check (d.date ())
    autoTester.check (d.time ())
    # named tuples not supported, need to convert
    autoTester.check (tuple (d.timetuple ()))
    autoTester.check (tuple (d.utctimetuple ()))

    # datetime comparisons
    d2 = d + delta
    d3 = d2 - delta
    autoTester.check (d)
    autoTester.check (d2)
    autoTester.check (d3)
    autoTester.check (d == d3)
    autoTester.check (d > d3)
    autoTester.check (d < d3)
    autoTester.check (d == d2)
    autoTester.check (d > d2)
    autoTester.check (d < d2)

4.32. Module itertools: almost all of Python’s itertools module

Testlet: module_itertools
from itertools import *
from math import pow

def fibonacci():
    a, b = 0, 1
    for i in range (10):
        yield a
        a, b = b, a + b

squares = [i * i for i in range (10)]

chars = 'thequickbrownfoxjumpsoverthelazydog'
        
def run (autoTester):
    autoTester.check ('islice count', list (islice (count (10, 2), 4, 40, 3)))
    autoTester.check ('islice cycle', list (islice (cycle (fibonacci ()), 15)))
    autoTester.check ('repeat', list (repeat (3.14, 15)))
    autoTester.check ('islice repeat', list (islice (repeat (2.74), 15)))
    autoTester.check ('accumulate', list (accumulate (range (5))))

    def add (total, element):
        return total + element
    
    autoTester.check ('accumulate', list (accumulate (['alamak', 'mirach', 'sirrah'], add)))
    
    autoTester.check ('chain', list (chain (fibonacci (), squares, chars)))
    autoTester.check ('chain.from_iterable', list (chain.from_iterable (['ape', 'node', 'mice', 'vim', 'sus', 'jet'])))
    
    selectors = [True, True, False, True, False, False, True, True, False, True]
    
    autoTester.check ('compress', list (compress (
        ['{}{}'.format (('take' if selector else 'leave'), index) for index, selector in enumerate (selectors)],
        selectors
    )))
    
    autoTester.check ('dropwhile', list (dropwhile (lambda x: x < 5, [1, 4, 6, 4, 1])))
    autoTester.check ('filterfalse', list (filterfalse (lambda x: x % 2, range (10))))
    
    things = [('animal', 'bear'), ('animal', 'duck'), ('plant', 'cactus'), ('vehicle', 'speed boat'), ('vehicle', 'school bus')]

    for key, group in groupby (things, lambda x: x [0]):
        for thing in group:
            autoTester.check ('A {} is a {}.' .format (thing[1], key))
        autoTester.check (' ')
        
    autoTester.check ('islice', list (islice ([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 2, 9, 2)))
        
    autoTester.check ('starmap', [int (x) for x in starmap (pow, [(2, 5), (3, 2), (10, 3)])])
    autoTester.check ('takewhile', list (takewhile (lambda x: x < 5, [1, 4, 6, 4, 1])))
    
    i1, i2 = tee (islice (count (), 5))
    autoTester.check ('tee', list (i1), list (i1), list (i2))
    
    autoTester.check ('product', list (product ('ABCD', 'xy')), list (product (range (2), repeat = 3)))

    autoTester.check ('permutations', list (permutations ('ABCD')), list (permutations ('ABCD', 2)))
    
    autoTester.check ('combinations',
        list (combinations ('ABCD', 2)),
        list (combinations ([1, 2, 3, 4, 5], 3)),
        list (combinations (islice (count (), 6), 4))
    )
    
    autoTester.check ('combinations_with_replacement',
        list (combinations_with_replacement ('ABCD', 2)),
        list (combinations_with_replacement ([1, 2, 3, 4, 5], 3)),
        list (combinations_with_replacement (islice (count (), 6), 4))
    )
    

4.33. Module math: almost all of Python’s math module

Testlet: module_math
from math import *

def _check(nr, autoTester):
    # we just compare the first 15 digits of floats due to precision deviations
    # in browser and CPython:
    if isinstance(nr, float):
        nr = str(nr)[:15]
    autoTester.check(nr)


def run (autoTester):
    check = lambda nr: _check(nr, autoTester)
    check (pi)
    check (e)
    
    check (exp (3))
    check (int (expm1 (5)))
    
    check (log (0.2))
    check (round (log (1024, 2)))
    check (log1p (5))
    check (int (log2 (257)))
    check (int (log10 (1001)))
    
    check (pow (3, 4.5))
    check (sqrt (25.1))
    
    check (sin (10))
    check (cos (10))
    check (tan (10))

    check (asin (0.5))
    check (acos (0.5))
    check (atan (0.5))
    check (atan2 (1, 2))
    
    check (int (hypot (3, 4.1)))
    
    check (degrees (pi/2.1))
    check (radians (90))
    
    check (sinh (1))
    check (cosh (1))
    check (tan (1))
    
    check (asinh (70))
    check (acosh (70))
    check (atan (70))
    
    check (floor (3.5))
    check (ceil (3.5))
    check (trunc (3.5))
    
    check (isnan (3))
    check (isnan (nan))
    
    

4.34. Module random: most important functions of Python’s random module

Manual_test: module_random
from random import *

result = ''

def output (any):
    result += any + '<br>\n'

for fixedSeed in (False, True):
    if fixedSeed:
        seed (3)
    else:
        seed ()

    output ('------ {} ------'.format ('fixed seed' if fixedSeed else 'auto seed'))
        
    output ('--- randint in [10, 20] ---')
    for i in range (20):
        output (randint (10, 20))

    output ('<br>\n--- choice ---')
    for i in range (20):
        output (choice ([1, 2, 3, 4, 5]))

    output ('<br>\n--- random ---')
    for i in range (20):
        output (random ())
        
    output ('<br>\n--- shuffle ---')
    aList = [0, 1, 2, 3, 4, 5, 6]
    output (aList)
    for i in range (7):
        shuffle (aList)
        output (aList)
    
    output ('<br>\n')
    
document.getElementById ('output') .innerHTML = result

4.35. Module re: transcryption of Python’s re module

Testlet: re/autotest
import org.transcrypt.autotester

import basic_pyre
import basic_jsre

autoTester = org.transcrypt.autotester.AutoTester ()

autoTester.run (basic_jsre, 'Basic JS RE Tests')
autoTester.run (basic_pyre, 'Basic Python RE Tests')

autoTester.done ()
Testlet: re/basictests

from org.transcrypt.stubs.browser import __pragma__, __symbols__, __envir__
import re
__pragma__("skip")
re.J = (1<<19)
re.JSSTRICT = re.J

def convertMappingDict(mdict):
    """ This method converts a mapping proxy object to
    a dict object. mapping proxies create read-only dicts
    but we don't have that concept in transcrypt yet.
    """
    ret = {}
    for k in mdict.keys():
        ret[k] = mdict[k]
    return(ret)

__pragma__("noskip")

testStr1 = "There,is,No,Time"
testStr2 = "som[23] In[23423] the[34].asd[934].234."
testStr3 = "s(43) d(03) asdfasd dsfsd(3) sd"
testStr4 = "Were an apple like an orange then apple orange no appleorange"

def checkMatchProperties(test, flags = 0):
    """ This test checks that properties on the match
    are reported correctly, and that they are read-only
    """
    result = re.search(",", testStr1, flags)
    if ( result is not None ):
        test.check( result.pos )
        test.check( result.endpos )
        test.check( result.group() )
        test.check( result.group(0) )
        test.check( result.string )

        # Check readonly props of match
        def assignPos():
            result.pos = 1
        test.check(test.expectException(assignPos))
        def assignEndPos():
            result.endpos = 1
        test.check(test.expectException(assignEndPos))
        def assignRe():
            result.re = "asdfasdf"
        test.check(test.expectException(assignRe))
        def assignStr():
            result.string = "asdf"
        test.check(test.expectException(assignStr))
        def assignLastGroup():
            result.lastgroup = "asdfasdf"
        test.check(test.expectException(assignLastGroup))
        def assignLastIndex():
            result.lastindex = 33
        test.check(test.expectException(assignLastIndex))
    else:
        test.checkPad("NULL", 11)


def checkRegexProperties(test, flags = 0):
    """ This test checks that the appropriate properties
    exist on the Regex object and that these properties
    are read-only.
    """
    r = re.compile(",", flags)
    if ( r is not None ):
        test.check( r.groups )
        test.check( r.pattern )
        test.check( r.flags )
        d = r.groupindex
        __pragma__('skip')
        d = convertMappingDict(d)
        __pragma__('noskip')
        test.check( d )
        # Check Read-only props on regex object
        def assignPattern():
            r.pattern = "asdfasdf"
        test.check(
            test.expectException(assignPattern)
        )
        def assignFlags():
            r.flags = "wer"
        test.check(
            test.expectException(assignFlags)
        )
        def assignGroups():
            r.groups = 1
        test.check(
            test.expectException(assignGroups)
        )
        def assignGroupIndex():
            r.groupindex = 34
        test.check(
            test.expectException(assignGroupIndex)
        )
    else:
        test.checkPad("NULL", 8)
        
def aValue (flag):   # Workaround for Python 3.6 enums
    result = flag.value
    return result if result else flag
        
def checkFlagsExist(test):
    test.check(aValue(re.T))
    test.check(aValue(re.I))
    test.check(aValue(re.IGNORECASE))
    test.check(aValue(re.M))
    test.check(aValue(re.MULTILINE))
    test.check(aValue(re.S))
    test.check(aValue(re.DOTALL))
    test.check(aValue(re.U))
    test.check(aValue(re.UNICODE))
    test.check(aValue(re.X))
    test.check(aValue(re.VERBOSE))
    test.check(aValue(re.A))
    test.check(aValue(re.ASCII))

def escapeTests(test):
    test.check(re.escape("buf[34]"))
    test.check(re.escape("C:\\asdf\\wewer\\"))
    test.check(re.escape("func(int a) { return(3)};"))

def checkIgnoreCase(test, flags = 0):
    test.check( re.search("as", testStr3, flags|re.I).pos )
    test.check( re.search("as", testStr3, flags|re.I).endpos )
    test.check( re.search("as", testStr3, flags|re.I).group() )
    test.check( re.search("as", testStr3, flags|re.I).group(0) )
    test.check( re.search("AS", testStr3, flags|re.I).pos )
    test.check( re.search("AS", testStr3, flags|re.I).endpos )
    test.check( re.search("AS", testStr3, flags|re.I).group() )
    test.check( re.search("AS", testStr3, flags|re.I).group(0) )

def checkSearchWithGroups(test, flags = 0):
    r = "\\[([\\d]+)\\]"
    test.check( re.compile(r, flags).groups )
    test.check( re.search(r, testStr2, flags).pos)
    test.check( re.search(r, testStr2, flags).endpos)
    test.check( re.search(r, testStr2, flags).groups())
    test.check( re.search(r, testStr2, flags).group())
    test.checkEval(lambda: re.search(r, testStr2, flags).group(0))
    test.checkEval(lambda: re.search(r, testStr2, flags).group(1))
    test.check( re.search(r, testStr2, flags).start())
    test.checkEval(lambda: re.search(r, testStr2, flags).start(0))
    test.checkEval(lambda: re.search(r, testStr2, flags).start(1))

    test.check( re.search(r, testStr2, flags).end())
    test.checkEval(lambda: re.search(r, testStr2, flags).end(0))
    test.checkEval(lambda: re.search(r, testStr2, flags).end(1))

    test.check( re.search(r, testStr2, flags).span())
    test.checkEval(lambda: re.search(r, testStr2, flags).span(0))
    test.checkEval(lambda: re.search(r, testStr2, flags).span(1))

    test.check( re.search(r, testStr2, flags).lastgroup)
    test.check( re.search(r, testStr2, flags).lastindex)

    for i in range(2,50):
        test.check(
            test.expectException(lambda: re.search(',', testStr1, flags).group(i))
        )

def checkMatchOps(test, flags = 0):
    test.check( re.match("asdf", "asdf", flags).pos )
    test.check( re.match(r"asdf", "asdf", flags).endpos )
    test.check( re.match("asdf", "asdf", flags).groups() )
    test.check( re.match("a", "asdf", flags).pos )
    test.check( re.match("a", "asdf", flags).endpos )
    test.check( re.match("a", "asdf", flags).groups() )
    test.check( (re.match("s", "asdf", flags) is None) )
    test.check( (re.match(r"^s", "asdf", flags) is None) )
    test.check( (re.compile("^s", flags).match("asdf", 1) is None) )

def checkMatchWithNamedGroups(test, flags = 0):
    """
    """
    # Matches with named groups
    r = None
    try:
        r = re.compile(r"(?P<prefix>[a-zA-Z]+)://(?P<suffix>[^/]*)", flags)
    except Exception as exc:
        test.checkPad(None, 15)

    if ( r is not None ):
        test.check(r.groups)
        test.check(r.pattern)
        d = r.groupindex
        __pragma__('skip')
        d = convertMappingDict(d)
        __pragma__('noskip')
        test.check( d )

        m = r.match("http://asdf")
        test.check( m.groups() )
        test.check( m.group() )
        test.check( m.group(0) )
        test.check( m.group(1) )
        test.check( m.group("prefix") )
        test.check( m.group("suffix") )

        m = r.match("ftp://192.168.1.1")
        test.check( m.group() )
        test.check( m.group(0) )
        test.check( m.group(1) )
        test.check( m.group("prefix") )
        test.check( m.group("suffix") )
        m = r.match("555-5555")
        test.check(m)

    try:
        r = re.compile(r"(?P<country>\d{1,3})-(?P<areacode>\d{3})-(?P<number>\d{3}-\d{4})", flags)
    except:
        test.checkPad(None, 13)

    if ( r is not None ):
        test.check(r.groups)
        test.check(r.pattern)
        d = r.groupindex
        __pragma__('skip')
        d = convertMappingDict(d)
        __pragma__('noskip')
        test.check( d )

        m = r.match("1-234-567-9012")
        test.check(m.groups())
        test.check(m.group())
        test.check(m.group(0))
        test.check(m.group(1))
        test.check(m.group(2))
        test.check(m.group(3))

        test.check( m.group("country") )
        test.check( m.group("areacode") )
        test.check( m.group("number") )

        m = r.match("adfs;")
        test.check(m)

def checkMatchWithGroups(test, flags = 0):
    rgx = re.compile(r'(\w)(\w)(\w)?', flags)
    test.check(rgx.pattern)
    test.check(rgx.groups)
    m = rgx.match('abc')
    if m:
        test.check(m.group(0))
        test.check(m.group(1))
        test.check(m.group(1, 2))
        test.check(m.group(2, 1))
    else:
        test.checkPad(None, 4)

    # groups() with default value

    m = rgx.match('ab')
    if m:
        test.check(m.groups(0))
    else:
        test.checkPad(None, 1)

    # Match with group that is non-captured
    rgx = re.compile(r'(?:[\w\s]+)\[(\d+)\]', flags)
    test.check(rgx.pattern)
    test.check(rgx.groups)

    m = rgx.match("asdf[23]")
    if m:
        test.check( m.groups() )
        test.check( m.group(0) )
        test.check( m.group(1) )
        test.check( test.expectException( lambda: m.group(2) ) )
    else:
        test.checkPad(None, 4)


def checkCommentGroup(test, flags = 0):
    """ Comment Groups are only supported in Python so will
    likely fail in javascript only mode
    """
    r = None
    try:
        r = re.compile(r'a(?#foobar)b', flags)
    except:
        test.checkPad(None,4)

    if ( r is not None ):
        test.check(r.groups)
        test.check(r.pattern)
        test.check(r.search("ab").group())
        test.check(r.search("er"))

    try:
        r = re.compile(r'([\d]+)(?#blarg)\[\]', flags)
    except:
        test.checkPad(None, 4)
        return

    test.check( r.groups )
    test.check( r.pattern )
    test.check( r.search("1234[]").group())
    test.check( r.search("asdf[]"))


def checkFullMatchOps(test, flags = 0):
    test.check( (re.fullmatch("asdf", "asdf", flags).pos))
    test.check( (re.fullmatch("asdf", "asdf", flags).endpos))
    test.check( (re.fullmatch("as", "asdf", flags) is None))
    test.check( (re.fullmatch("q", "asdf", flags) is None))
    test.check( (re.compile("o[gh]", flags).fullmatch("dog") is None))
    test.check( (re.compile("o[gh]", flags).fullmatch("ogre") is None))

    m = re.compile("o[gh]", flags).fullmatch("doggie",1,3)
    if m:
        test.check(m.pos)
        test.check(m.endpos)
    else:
        test.checkPad(None,2)

def checkFindAllOps(test, flags = 0):
    test.check(re.findall(",", testStr1, flags)) # No Caps
    test.check(re.findall("\\[([\\d]+)\\]", testStr2, flags)) # 1 Cap
    r = "([^\d\s]+\\(([\d]+)\\))"
    test.check(re.compile(r, flags).groups)
    test.check(re.findall(r, testStr3, flags)) # 2 Caps

def checkSplitOps(test, flags = 0):
    test.check(re.split(",", testStr1, 0, flags))

    test.check(re.split("(apple|orange)",testStr4, 0, flags))
    test.check(re.split("\\[([\\d]+)\\]", testStr2, 0, flags))
    r = re.compile(",", flags)
    test.check(r.split(testStr1, 0))
    test.check(r.split(testStr1, 1))
    test.check(r.split(testStr1, 2))
    test.check(r.split(testStr1, 3))
    test.check(r.split(testStr1, 4))

    r = re.compile("\\[([\\d]+)\\]", flags)
    test.check(r.split(testStr2,0))
    test.check(r.split(testStr2,1))
    test.check(r.split(testStr2,2))
    test.check(r.split(testStr2,3))
    test.check(r.split(testStr2,4))

def checkSubOps(test, flags = 0):
    def dashrepl(matchobj):
        if matchobj.group(0) == '-':
            return ' '
        else:
            return '-'
    test.check(re.sub('-{1,2}', dashrepl, 'pro----gram-files',0, flags))
    test.check(re.sub('-{1,2}', '4', 'pro----gram-files',0, flags))
    test.check(re.subn('-{1,2}', dashrepl, 'pro----gram-files',0,flags))
    test.check(re.subn('-{1,2}', '4', 'pro----gram-files',0,flags))

def checkSyntaxErrors(test, flags = 0):
    test.check(test.expectException( lambda: re.compile(r')', flags)))
    test.check(test.expectException( lambda: re.compile("a\\", flags)))
    test.check(test.expectException( lambda: re.compile(r'a[b', flags)))
    test.check(test.expectException( lambda: re.compile(r'(abc', flags)))
    test.check(test.expectException( lambda: re.compile(r')(', flags)))
    test.check(test.expectException( lambda: re.compile(r'))', flags)))
    test.check(test.expectException( lambda: re.compile(r'a[b-a]', flags)))
    test.check(test.expectException( lambda: re.compile(r'*a', flags)))

def checkFindIter(test, flags = 0):
    """ Test the finditer method
    """
    p = "\\[([\\d]+)\\]"
    r = re.compile(p, flags)
    test.check( r.groups )

    iret = r.finditer(testStr2)
    for m in iret:
        test.check(m.pos)
        test.check(m.endpos)
        test.check(m.string)
        test.check(m.lastindex)
        test.check(m.groups())
        test.check(m.group(0))
        test.check(m.group(1))
        test.check(test.expectException( lambda: m.group(2) ))
        test.check(test.expectException( lambda: m.group(2342)))
        test.check(test.expectException( lambda: m.group("asdf")))
        test.check(m.start(0))
        test.check(m.start(1))
        test.check(test.expectException( lambda: m.start("asdf")))
        test.check(m.end(0))
        test.check(m.end(1))
        test.check(test.expectException( lambda: m.end("asdf")))


def checkWithFlags(test, flags = 0):
    """ This checks the regex with flags called out in the
    string, for example (?i) for ignore case.
    This is a python only feature.
    """
    try:
        r = re.compile(r'(?i)aba', flags)
    except:
        test.checkPad(None, 5)
        return

    test.check(r.groups)
    test.check(r.pattern)

    m = r.search("aBA")
    test.check(m.group() )
    test.check(m.groups())

    m = r.match("aAa")
    test.check(m)

    m = r.match("ABA")
    test.check(m.group())

    m = r.match("abA")
    test.check(m.group())


def checkConditionalGroups(test, flags = 0):
    """ Check conditional groups - this is a python only
    feature - will likely faily in the js strict mode
    """
    rgx = None
    try:
        rgx = re.compile(r'(a)?(b)?(?(1)a|c)(?(2)b)', flags)
    except:
        test.checkPad(None, 12)

    if ( rgx is not None ):
#        test.check(rgx.groups)                                             # !!! @JdeH temporarily disabled this
        test.check(rgx.pattern)
        test.checkEval(lambda: rgx.match('abab').group())
        test.checkEval(lambda: rgx.match('aa').group())
        test.checkEval(lambda: rgx.match('bcb').group())
        test.checkEval(lambda: rgx.match('c').group())
        test.checkEval(lambda: rgx.match('abcb'))
        # PyRegex needs to use n_splits from `translate` for this to work
        # test.checkEval(lambda: rgx.match('c').groups())                   # !!! @JdeH temporarily disabled this
        # test.checkEval(lambda: rgx.split("ababbababcdjsabbabdbab"))       # !!! @JdeH temporarily disabled this
        test.checkEval(lambda: rgx.sub("jumbo", "ababsdf rexababwer"))
        test.checkEval(lambda: rgx.sub("shrimp", "shipbcb shootc aardvark"))
        # test.checkEval(lambda: rgx.findall("ababxaaxcebbcxababeded"))     # !!! @JdeH temporarily disabled this

    try:
        rgx = re.compile(r'(a)?(b)?(?(1)a|c)(?(2)b|d)', flags)
    except:
        test.checkPad(None, 6)
        return

    # test.check(rgx.groups)                                                # !!! @JdeH temporarily disabled this
    test.check(rgx.pattern)
    test.checkEval(lambda: rgx.match('abab').group())
    test.checkEval(lambda: rgx.match('aad').group())
    test.checkEval(lambda: rgx.match('bcb').group())
    test.checkEval(lambda: rgx.match('bcb').group())
Testlet: re/basic_pyre
# File: basic_pyre.py
#
# This file contains the basic regex tests run on the
# python translated regex expressions.
#

from org.transcrypt.stubs.browser import __pragma__
import re
from basictests import *

def run (test):
    """ basic tests of the re engine. The point is to
    exercise most of the methods to make sure they behave as
    expected. These tests are expected to provide exhaustive
    coverage of the regex engine.
    """
    checkFlagsExist(test)

    escapeTests(test)
    checkMatchProperties(test)
    checkRegexProperties(test)

    checkIgnoreCase(test)

    checkSearchWithGroups(test)
    checkMatchOps(test)
    checkMatchWithGroups(test)
    # checkMatchWithNamedGroups(test)           # !!! @JdeH temporarily disabled this
    checkFullMatchOps(test)
    checkFindAllOps(test)
    checkSplitOps(test)
    checkSubOps(test)
    checkSyntaxErrors(test)
    checkConditionalGroups(test)
    checkCommentGroup(test)
    checkWithFlags(test)

    checkFindIter(test)
Testlet: re/basictests
from org.transcrypt.stubs.browser import __pragma__
import re
__pragma__("skip")
re.J = (1<<19)
re.JSSTRICT = re.J
__pragma__("noskip")

from basictests import *

def run (test):
    """ basic tests of the re engine. The point is to
    exercise most of the methods to make sure they behave as
    expected. These tests are expected to provide exhaustive
    coverage of the regex engine.
    """
    checkFlagsExist(test)
    escapeTests(test)
    checkMatchProperties(test, re.JSSTRICT)
    checkRegexProperties(test, re.JSSTRICT)

    checkIgnoreCase(test, re.JSSTRICT)

    checkSearchWithGroups(test, re.JSSTRICT)
    checkMatchOps(test, re.JSSTRICT)
    checkMatchWithGroups(test, re.JSSTRICT)
    #checkMatchWithNamedGroups(test, re.JSSTRICT)

    checkFullMatchOps(test, re.JSSTRICT)
    checkFindAllOps(test, re.JSSTRICT)
    checkSplitOps(test, re.JSSTRICT)
    checkSubOps(test, re.JSSTRICT)
    checkSyntaxErrors(test, re.JSSTRICT)
    #checkConditionalGroups(test, re.JSSTRICT)
    #checkCommentGroup(test, re.JSSTRICT)
    #checkWithFlags(test, re.JSSTRICT)

    checkFindIter(test, re.JSSTRICT)

4.36. Module time: transcryption of Python’s time module

Testlet: time/testlet0
import org.transcrypt.autotester

import testlet0, strptime, mult_time

autoTester = org.transcrypt.autotester.AutoTester ()

autoTester.run (testlet0, 'testlet0')
autoTester.run (strptime, 'strptime')
autoTester.run (mult_time, 'mult_time')

autoTester.done ()
Testlet: time/testlet0
''' general functions '''
import time

ts = 1468968009.638596 # a test timestamp
hy = 6 * 30 * 86400 # around half a year
# accommodate the offset between python and transcrypt run:
def run (autoTester):
    c = autoTester.check
    # rounding this one much, since test res is not updated when code not
    # changes (?)
    c('time():'         , int(time.time() / 1000))
    c('altzone:'        , time.altzone)
    c('timelen:'        , len(str(int(time.time()))))
    c('localtime:'      , list(time.localtime(ts)))
    c('ltime_no_dst:'   , list(time.localtime(ts + hy)))
    c('gmtime:'         , list(time.gmtime(ts)))
    c('daylight:'       , bool(time.daylight))
    c('timezone:'       , time.timezone)
    # c('tzname:'         , time.tzname) # Won't work under Windows 10, since it mixes up CET/CEST and WET/WEST and names CEST deviantly.
    # more tests in other testlests

Testlet: time/mult_time
'''
testing strftime.
'''

import time


def run (autoTester):
    t = [2000, 1, 1, 1, 1, 1, 1, 1, 0]
    def check(fmt):
        s = time.mktime(tuple(t))
        autoTester.check('gmtime'   , tuple(time.gmtime(int(s))))
        autoTester.check('localtime', tuple(time.localtime(int(s))))
        autoTester.check('mktime'   , int(s))
        autoTester.check('ctime'    , int(s))

    for hour in (0, 1, 12, 14, 23):
        t[3] = hour
        for f in (
             '%p %I.%d.%Y'
            ,'%b .%d.%y'
            ,'%b .%d.%Y'
            ,'%d%m%Y%H:%M:%S%p'
            ,'%b .%d.%Y'
            ,'M%m.%d.%Y'
            ,'%m.%d.%Y'
            ,'%m.%d.%Y'
            ,'%b .%d.%Y'
            ,'%m.%d.%Y'
            ,'%B %d.%Y'
            ,'%a %b %d %H:%M:%S %Y'
            ,'%d.%m.%Y %I:%M:%S%p'
            ,'%a%b %d %H:%M:%S %Y'
            ,'%a%b%d %H:%M:%S %Y'
            ,'%a%b%d%H:%Mx%S%Y'
            ,'%a%b%d%H:%Mxx%S%Y'
            ,'%a%b%d%H:%Mxx%S%Y +000'
            ,' %a%b%d%H:%Mxx%S%Y +000 '
            ): check(f)

    autoTester.check('asctime', t)



Testlet: time/strptime
'''
testing strptime.

Note, Py3 bug:

while true; do
    python3.5 -c "import time; print(tuple(time.strptime('nov 1.1.1900', '%b %m.%d.%Y')))"
done

=> we simply cannot test conflicting %b %m switches,
it decides per run which one it takes(!!!), so autotest would fail randomly.

Verified with 3.4, 3.5 on mac and linux.

Root cause explained here: https://github.com/JdeH/Transcrypt/issues/85
'''

import time

# Note: The localized names for months and weekdays assumed to be english here.
# And the js implementation takes the names of the locale. That may fail the
# tests in other areas of the world. tried with export LANG other locales but
# did not get an error though.
# In any case the Js implementation of the checking the weekdays and monthnames
# should be safe.

def run (autoTester):
    def check(t, fmt):
        s = tuple(time.strptime(t, fmt))
        autoTester.check(' '.join([t, '[', fmt, '] = ']), s)

    check('jan .1.1902'               , '%b .%d.%Y')
    check('3112199912:00:00pm'         , '%d%m%Y%H:%M:%S%p')
    check('FEb .1.1902'               , '%b .%d.%Y')
    check('M1.1.1901'                  , 'M%m.%d.%Y')
    check('2.1.1900'                   , '%m.%d.%Y')
    check('6.1.2000'                   , '%m.%d.%Y')
    check('nov .1.1900'                , '%b .%d.%Y')
    check('2.1.1900'                   , '%m.%d.%Y')
    check('december 1.1999'            , '%B %d.%Y')
    check('Tue Jul 18 19:32:11 2016'   , '%a %b %d %H:%M:%S %Y')
    check('31.12.1999 12:00:00pm'      , '%d.%m.%Y %I:%M:%S%p')
    check('TueJul 18 19:32:11 2016'    , '%a%b %d %H:%M:%S %Y')
    check('TueJul18 19:32:11 2016'     , '%a%b%d %H:%M:%S %Y')
    check('TueJul1819:32x112016'       , '%a%b%d%H:%Mx%S%Y')
    check('TueJul1819:32xx112016'      , '%a%b%d%H:%Mxx%S%Y')

4.37. Modules: hierarchical, both local to the project and global url-based

Testlet: modules
import modules.mod1.mod11.mod111
import modules.mod3
import modules.mod1.mod11.mod112
import modules.mod1
import modules.mod1.mod11
import modules.mod2
import modules.mod2.mod21
import modules.mod2.mod22

import modules.mod1.mod11.mod111 as aliasMod111
import modules.mod1 as aMod1

from modules.mod1.mod11 import mod111, mod112

from modules.mod2 import mod21 as aMod21, mod22 as aMod22

from modules.mod3 import *

from modules.mod1.mod11.mod111 import A

from modules import mod4

a = modules.mod1.mod11.mod111.A (12345)
pi = modules.mod1.pi
f = modules.mod2.f

def run (autoTester):
    # Import without 'as'
    autoTester.check ('modules')
    autoTester.check (a.f ())
    autoTester.check (modules.mod1.mod11.mod112.f ())
    autoTester.check (modules.mod1.mod11.e)
    autoTester.check (pi)
    autoTester.check (f (102030))
    autoTester.check (modules.mod2.mod21.f ())
    B = modules.mod2.mod22.B
    b = B ()
    autoTester.check (b.x)
    autoTester.check (modules.mod3.x)
    
    # Import with 'as'
    a2 = aliasMod111.A (6789101112)
    autoTester.check (a2.f ())
    autoTester.check (aMod1.pi)
    
    # From ... import without 'as'
    a3 = mod111.A (100.001)
    autoTester.check (a3.f ())
    autoTester.check (mod112.f ())
    
    # From ... import with 'as'
    autoTester.check (aMod21.f ())
    autoTester.check (aMod22.B () .x)
    
    # From ... import *
    autoTester.check (mod3Hundred)
    autoTester.check (mod3GetTwoHundred ())
    autoTester.check (A (123.321) .f ())

    # Circular import (between mod4 and mod5)
    autoTester.check(mod4.mod4Add2FromMod5(449))

4.38. Nonlocals

Testlet: nonlocals
def run (autoTester):
    test1 = 1
    test2 = 2
    
    def f ():
        test1 = 10
        
        nonlocal test2
        test2 = 20
        
        autoTester.check (test1, test2)
        
    f ()
    autoTester.check (test1, test2)     

4.39. Operator overloading

Testlet: operator_overloading
from org.transcrypt.stubs.browser import __pragma__

class Matrix:
    def __init__ (self, nRows, nCols, elements = []):
        self.nRows = nRows
        self.nCols = nCols
        
        if len (elements):
            self._ = elements
        else:
            self._ = [[0 for col in range (nCols)] for row in range (nRows)]
        
    def __matmul__ (self, other):
        result = Matrix (self.nRows, other.nCols)
        for iTargetRow in range (result.nRows):
            for iTargetCol in range (result.nCols):
                for iTerm in range (self.nCols):
                    result._ [iTargetRow][iTargetCol] += self._ [iTargetRow][iTerm] * other._ [iTerm][iTargetCol]
        return result
                
    def __imatmul__ (self, other):
        # True in-place multiplication not yet implemented in compiler
        # It currently translates m1 @= m2 to m1 = m1 @ ms and uses __matmul__ instead
        # This fake __imatmul__ is just for CPython , allowing back to back testing
        return self.__matmul__ (other)
        
    def __mul__ (self, other):
        if type (other) == Matrix:
            result = Matrix (self.nRows, self.nCols)
            for iRow in range (self.nRows):
                for iCol in range (self.nCols):
                    result._ [iRow][iCol] = self._ [iRow][iCol] * other._ [iRow][iCol]   
            return result
        else:  # other is a scalar
            return self.__rmul__ (other)
                
    def __rmul__ (self, scalar):    # Only called if left operand is scalar, all other cases will call __mul__
        result = Matrix (self.nRows, self.nCols)
        for iRow in range (self.nRows):
            for iCol in range (self.nCols): 
                result._ [iRow][iCol] = scalar * self._ [iRow][iCol]
        return result
    
    def __imul__ (self, other):
        return self.__mul__ (other)
                
    def __add__ (self, other):
        result = Matrix (self.nRows, self.nCols)
        for iRow in range (self.nRows):
            for iCol in range (self.nCols):
                result._ [iRow][iCol] = self._ [iRow][iCol] + other._ [iRow][iCol]
        return result
        
    # No __iadd__, to test fallback to __add__
    
    def __getitem__ (self, index):
        return self._ [index]

    def __setitem__ (self, index, value):
        self._ [index] = value
        
    def __repr__ (self):
        return repr (self._)
        
    def __floordiv__ (self, other):
        return 'Overloading __floordiv__ has no meaning for matrices'
        
    def __truediv__ (self, other):
        return 'Overloading __truediv__ has no meaning for matrices'
        
class Functor:
    def __init__ (self, factor):
        self.factor = factor
        
    __pragma__ ('kwargs')
    def __call__ (self, x, y = -1, *args, m = -2, n, **kwargs):
        return (
            self.factor * x,
            self.factor * y,
            [self.factor * arg for arg in args],
            self.factor * m,
            self.factor * n,
            # !!! [self.factor * kwargs [key] for key in sorted (kwargs.keys ())] Add supoprt for keys () on kwargs
        )
    __pragma__ ('nokwargs')
    
f = Functor (10)

__pragma__ ('kwargs')
def g (x, y = -1, *args, m = -2, n, **kwargs):
    return (x, y, args, m, n) # !!! , [kwargs [key] for key in sorted (kwargs.keys ())]) Add support for keys () on kwargs
__pragma__ ('nokwargs')
        
def run (autoTester):
    m0 = Matrix (3, 3, [
        [1, 2, 3],
        [4, 5, 6],
        [7, 8, 10]
    ])
    
    m1 = Matrix (3, 3, [
        [10, 20, 30],
        [40, 50, 60],
        [70, 80, 90]
    ])
    
    m4 = Matrix (3, 3, [
        [1, 1,  2],
        [2, 2,  3],
        [3, 3, -5]
    ])
    
    m5 = Matrix (3, 3, [
        [1, 1,  2],
        [2, 2,  3],
        [3, 3, -5]
    ])
        
    x = 3
    y = x * 4 * x
    fast = 2 * 3
    fast += 1
    
    __pragma__ ('opov')
    
    m1 [1][2] = m0 [1][2]
    slow = 2 + 3
    m2 = m0 * m1  + m1 * (m0 + m1)
    m3 = 2 * (2 * m0 * 3 * m1 + m2 * 4) * 2

    autoTester.check (m0 [1][1], m0 [1][2], m1 [1][1], m1 [1][2])

    m1 += m0
    m2 *= m1
    
    m5 @= m4
    m6 = m0 @ m1
    
    autoTester.check (m0 / m1)
    autoTester.check (m0 // m1)
    
    __pragma__ ('noopov')
    
    fast2 = 16 * y + 1
    fast *= 2
    
    autoTester.check (m0, m1)
    autoTester.check (x, y)
    autoTester.check (m2)
    autoTester.check (m3)
    autoTester.check (m5)
    autoTester.check (m6)
    autoTester.check (fast, slow, fast2)
    
    x = 'marker'
    
    __pragma__ ('opov')
    autoTester.check (f (3, 4, 30, 40, m = 300, n = 400, p = 3000, q = 4000))
    autoTester.check (g (3, 4, 30, 40, m = 300, n = 400, p = 3000, q = 4000))
    
    autoTester.check (set ((1, 2, 3)) == set ((3, 2, 1)))
    autoTester.check (set ((1, 2, 3)) != set ((3, 2, 1)))
    autoTester.check (set ((1, 3)) == set ((3, 2, 1)))
    autoTester.check (set ((1, 3)) != set ((3, 2, 1)))
    autoTester.check (set ((1, 2)) < set ((3, 2, 1)))
    autoTester.check (set ((1, 2, 3)) <= set ((3, 2, 1)))
    autoTester.check (set ((1, 2, 3)) > set ((2, 1)))
    autoTester.check (set ((1, 2, 3)) >= set ((3, 2, 1)))
    
    autoTester.check ((1, 2, 3) == (1, 2, 3))
    autoTester.check ([1, 2, 3] == [1, 2, 3])
    autoTester.check ((1, 2, 3) != (1, 2, 3))
    autoTester.check ([1, 2, 3] != [1, 2, 3])
    autoTester.check ((2, 1, 3) == (1, 2, 3))
    autoTester.check ([2, 1, 3] == [1, 2, 3])
    autoTester.check ((2, 1, 3) != (1, 2, 3))
    autoTester.check ([2, 1, 3] != [1, 2, 3])
    __pragma__ ('noopov')
    
    class Bitwise:
        def __lshift__ (self, other):
            autoTester.check ('lshift')
            
        def __rlshift__ (self, other):
            autoTester.check ('rlshift')
            
        def __rshift__ (self, other):
            autoTester.check ('rshift')
            
        def __rrshift__ (self, other):
            autoTester.check ('rrshift')
            
        def __or__ (self, other):
            autoTester.check ('or') 
            
        def __ror__ (self, other):
            autoTester.check ('ror')
            
        def __xor__ (self, other):
            autoTester.check ('xor')
            
        def __rxor__ (self, other):
            autoTester.check ('rxor')
            
        def __and__ (self, other):
            autoTester.check ('and')
            
        def __rand__ (self, other):
            autoTester.check ('rand') 

    bitwise = Bitwise ()
    
    __pragma__ ('opov')
    
    bitwise << []
    [] << bitwise
    autoTester.check (32 << 2)
    
    bitwise >> []
    [] >> bitwise
    autoTester.check (32 >> 2)
    
    bitwise | []
    [] | bitwise
    autoTester.check (1 | 4)
    
    bitwise ^ []
    [] ^ bitwise
    autoTester.check (11 ^ 13)
    
    bitwise & []
    [] & bitwise
    autoTester.check (12 & 20)
    
    a = 32
    a <<=2
    autoTester.check (a)
    
    __pragma__ ('noopov')
    
    autoTester.check (32 << 2)
    autoTester.check (32 >> 2)
    autoTester.check (1 | 4)
    autoTester.check (11 ^ 13)
    autoTester.check (12 & 20)
    
    a = 32
    a <<= 2
    autoTester.check (a)
    
    class A:
        def __init__ (self):
            self.b = {}
            
    a = A ()
    a.b ['c'] = 'd'
        
    __pragma__('opov')
    a.b ['c'] += 'e'
    __pragma__('noopov')
    
    autoTester.check (a.b ['c'])

4.40. Properties

Testlet: properties
class A:
    p = 1234
    def getX (self):
        return self._x

    def setX (self, value):
        self._x = value
            
    def getY (self):
        return self._y

    def setY (self, value):
        self._y = 1000 + value  # Weird but should be possible
        
    def getY2 (self):
        return self._y

    def setY2 (self, value):
        self._y = value
        
    def getT    (self):
        return self._t

    def setT (self, value):
        self._t = value
        
    def getU (self):
        return self._u + 10000

    def setU (self, value):
        self._u = value - 5000
            
    x, y, y2 = property (getX, setX), property (getY, setY), property (getY2, setY2)
    t = property (getT, setT)
    u = property (getU, setU)
    
A.q = 5678

class B:
    def getZ (self):
        return self.z_
    
    def setZ (self, value):
        self.z_ = value
        
    z = property (getZ, setZ)
    
class C:
    def __init__ (self):
        self.offset = 1234

    def getW (self):
        return self.w_ + self.offset
        
    def setW (self, value):
        self.w_ = value - self.offset
        
    w = property (getW, setW)
    
def run (autoTester):
    a1 = A ()
    a2 = A ()

    a1.y2 = 1000
    a2.y2 = 2000
    
    a1.x = 5
    a1.y = 6
    
    a2.x = 7
    a2.y = 8

    a1.t = 77
    a1.u = 88
        
    autoTester.check (a1.x, a1.y, a1.y2)
    autoTester.check (a2.x, a2.y, a2.y2)
    autoTester.check (a1.p, a2.p, a1.q, a2.q)
    
    autoTester.check (a1.t, a1.u)
    
    b = B ()
    c = C ()
    
    b.z = 100100
    c.z = 200200
    c.w = 300300
    
    autoTester.check (a1.x, b.z, c.z, c.w)
    
    c.w = 400400
    c.z = 500500
    b.z = 600600
    
    autoTester.check (a1.x, b.z, c.z, c.w)

4.41. Representation as text: the repr and str built-in functions

Testlet: reprtest

def run(test):
    """ Test the repr and string implementations
    """

    v = 1
    test.check( repr(v) )
    test.check( str(v) )
    v = "asdf"
    test.check( repr(v) )
    test.check( str(v) )
    v = True
    test.check( repr(v) )
    test.check( str(v) )
    v = False
    test.check( repr(v) )
    test.check( str(v) )
    v = 1.2
    test.check( repr(v) )
    test.check( str(v) )
    v = -31.2
    test.check( repr(v) )
    test.check( str(v) )
    v = 63e-12
    test.check( repr(v) )
    test.check( str(v) )
    v = 24e37
    test.check( repr(v) )
    test.check( str(v) )
    v = -34e-23
    test.check( repr(v) )
    test.check( str(v) )
    v = -89e32
    test.check( repr(v) )
    test.check( str(v) )
    v = None
    test.check( repr(v) )
    test.check( str(v) )
    v = [None]
    test.check( repr(v) )
    test.check( str(v) )
    v = [None, None]
    test.check( repr(v) )
    test.check( str(v) )
    v = [None, 1.02]
    test.check( repr(v) )
    test.check( str(v) )
    v = [1,3.000234]
    test.check( repr(v) )
    test.check( str(v) )
    v = [1,2,3]
    test.check( repr(v) )
    test.check( str(v) )
    v = [1.04, 2.03, 3.005]
    test.check( repr(v) )
    test.check( str(v) )
    v = ["asdf", 2.00009, "1234"]
    test.check( repr(v) )
    test.check( str(v) )
    v = set([1,2,3])
    test.check( repr(v) )
    test.check( str(v) )
    v = set([])
    test.check( repr(v) )
    test.check( str(v) )
    v = (1,2)
    test.check( repr(v) )
    test.check( str(v) )
    v = (3.4, 4.4)
    test.check( repr(v) )
    test.check( str(v) )
    v = (None, 5.32)
    test.check( repr(v) )
    test.check( str(v) )
    v = {}
    test.check( repr(v) )
    test.check( str(v) )
    v = { "a": 1 }
    test.check( repr(v) )
    test.check( str(v) )

    # @note - in python the dictionary key
    #     ordering is not specified. So the following tests
    #     cannot be reliably completed when there are more than
    #     one key in a dict - so this test coverage was skipped for now.

    d = { "asdf": 3.4 }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "qwer": "qwerqwer qwerqwer" }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "a9342" : None }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "nfdns" : True }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "alel;e;" : False }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "didi" : [True,False,True] }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "bibi" : [1,2,3] }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "gigi" : ["Asdf","qwer","rewer"] }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "hihi" : ("esdf","qwer","rewer") }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "jiji" : [None, None, None] }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "jiji" : (1.3, 3.4) }
    test.check( repr( d ) )
    test.check( str( d ) )

    d = { "jiji" : { "c" : 4 } }
    test.check( repr( d ) )
    test.check( str( d ) )

    class Test1(object):
        def __init__(self, val):
            self._val = val

        def __str__(self):
            return("[Test1 {}]".format(self._val))

        def __repr__(self):
            return(str(self))

    class Test2(object):
        def __init__(self, val):
            self._val = val

        def __repr__(self):
            return("[Test2 {},{}]".format(self._val, self._val*2))

        def __str__(self):
            return( repr(self) )

    class Test3(Test2):
        def __str__(self):
            return("[Test3 {}]".format(self._val))

    class Test4(object):
        def __init__(self, val):
            self._val = val

        def __repr__(self):
            return("[Test4 {}]".format(self._val))


    t1 = Test1(2)
    test.check( repr(t1) )
    test.check( str(t1) )
    t1 = Test1(4.5)
    test.check( repr(t1) )
    test.check( str(t1) )
    t1 = Test1("blarg")
    test.check( repr(t1) )
    test.check( str(t1) )
    t1 = Test1([1,2,3])
    test.check( repr(t1) )
    test.check( str(t1) )

    t2 = Test2(3)
    test.check( repr(t2) )
    test.check( str(t2) )
    t2 = Test2(7.6)
    test.check( repr(t2) )
    test.check( str(t2) )
    t2 = Test2(-8.9)
    test.check( repr(t2) )
    test.check( str(t2) )

    t3 = Test3(8)
    test.check( repr(t3) )
    test.check( str(t3) )

    t3 = Test3(3.4)
    test.check( repr(t3) )
    test.check( str(t3) )

    test.check( repr( [t1,t2,3] ) )

    d = { "irew" : t1 }
    test.check( repr( d ) )
    test.check( str( d ) )
    d = { "irew" : [t1,t2,t3] }
    test.check( repr( d ) )
    test.check( str( d ) )

    t4 = Test4("qwer")
    test.check( repr(t4) )
    test.check( str(t4) )

4.42. Set comprehensions

Testlet: set_comprehensions
def run (autoTester):
    even = {2 * i for i in [0, 9, 1, 7, 2, 8, 3, 6, 4, 5]}
    autoTester.check (even)
    
    odd = {2 * i + 1 for i in [5, 6, 7, 8, 9, 4, 3, 1, 2, 0]}
    autoTester.check (odd)
    
    even.add (12)
    even.add (12)
    autoTester.check (even)
    
    even.discard (12)
    even.discard (12)
    autoTester.check (even)
    
    uni = even.union (odd)
    autoTester.check (uni)
    
    autoTester.check (odd.isdisjoint (even))
    autoTester.check (uni.isdisjoint (even))
        
    autoTester.check (even.issuperset (uni))
    autoTester.check (uni.issuperset (even))
    
    autoTester.check (even.issubset (uni))
    autoTester.check (uni.issubset (even))
    
    first = {4, 1, 0, 5, 3, 2, 6}
    autoTester.check (first)
    
    second = {3, 5, 6, 9, 4, 7, 8}
    autoTester.check (second)
    
    inter = first.intersection (second)
    autoTester.check (inter)
    
    diff = first.difference (second)
    autoTester.check (diff)
    
    symDiff = first.symmetric_difference (second)
    autoTester.check (symDiff)
    
    aSet = {200, 4, 5, 100}
    aSet.update (first, symDiff, second)
    autoTester.check (aSet)
    

4.43. Super

The super () builtin function is supported for cases where there’s exactly one path upwards to exactly one matching method. This covers most use cases, even in a diamond class hierarchy, and results in fast and compact code. In case of more than one path, possibly to more than one matching method, use explicit class names, as shown in the example below.

Testlet: builtin_super
def run (autoTester):
    def show (*args):
        autoTester.check (*args)
        # print (*args) # Leave in for debugging purposes

    class R:
        def __init__ (self, a, b):
            self.a = a
            self.b = b
            
    class A (R):
        def __init__ (self, a, b, c):
            super () .__init__ (a, b)
            self.c = c

        def f (self, x, y):
            show ('A.f:', x, y, self.a, self.b, self.c)
            
        def g (self, x, y):
            show ('A.g:', x, y)
            
    class B (R):
        def __init__ (self, a, b, d):
            super () .__init__ (a, b)
            self.d = d

        def f (self, x, y):
            show ('B.f:', x, y, self.a, self.b, self.d)
            
        def h (self, x, y):
            show ('A.h:', x, y, self.a, self.b, self.d)

    class C (A):
        def __init__ (self, a, b, c):
            super () .__init__ (a, b, c)
        
        def f (self, x, y):
            super () .f (x, y)
            show ('C.f:', x, y, self.a, self.b, self.c)
            
    class D (B):
        def __init__ (self, a, b, d):
            super () .__init__ (a, b, d)
        
        def f (self, x, y):
            super () .f (x, y)
            show ('D.f:', x, y, self.a, self.b, self.d)
            
    # Diamond inheritance, use super () only to call exactly one target method via unique path.
    # In case of multiple target methods or multiple paths, don't use super (), but refer to ancestor classes explicitly instead
    class E (C, D):        
        def __init__ (self, a, b, c, d):
            R.__init__ (self, a, b) # Inherited via multiple legs of a diamond, so call explicitly
            self.c = c              # Could also have used C.__init__, but symmetry preferred
            self.d = d              # Don't use both C.__init__ and D.__init__, since R.__init__ will be called by both
                                    # That's harmless here, but not always

        def f (self, x, y):
            C.f (self, x, y)        # Ambiguous part of diamond, don't use super ()
            D.f (self, x, y)        # Ambiguous part of diamond, don't use super ()
            show ('E.f:', x, y, self.a, self.b, self.c, self.d)
            
        def g (self, x, y):
            super () .g (x, y)      # Unique, using super () is OK
            show ('E.g:', x, y, self.a, self.b, self.c, self.d)
            
        def h (self, x, y):
            super () .h (x, y)      # Unique, using super () is OK
            show ('E.h:', x, y, self.a, self.b, self.c, self.d)
           
    rr = R (100, 200)

    show ('--1--')

    a = A (101, 201, 301)
    a.f (711, 811)
    a.g (721, 821)

    show ('--2--')

    b = B (102, 202, 302)
    b.f (712, 812)
    b.h (732, 832)

    show ('--3--')

    c = C (103, 203, 303)
    c.f (713, 813)
    c.g (723, 823)

    show ('--4--')

    d = D (104, 204, 304)
    d.f (714, 814)
    d.h (734, 834)

    show ('--5--')

    e = E (105, 205, 305, 405)
    e.f (715, 815)
    e.g (725, 825)
    e.h (735, 835)

4.44. Simple and augmented assignment

Testlet: simple_and_augmented_assignment
class A:
    def __init__ (self):
        self.i = 0
        
    def f (self):
        return self.i

a = A ()
        
def run (autoTester):
    x = 3
    y = 5
    z = x + y
    autoTester.check (z)
    
    l = [1, 2, 3]
    l [1] = l [2]
    autoTester.check (l)
    
    # Should generate x++
    x += 1
    autoTester.check (x)
    x += +1
    autoTester.check (x)
    x -= -1
    autoTester.check (x)
    
    # Should generate y--
    y -= 1
    autoTester.check (y)
    y -= +1
    autoTester.check (y)
    y += -1
    autoTester.check (y)
    
    x += -3
    autoTester.check (x)
    
    x += 6
    autoTester.check (x)
    
    y -= 3
    autoTester.check (y)
    
    l [1] += l [1]
    autoTester.check (l)
    
    x += y
    y += x
    
    autoTester.check (x, y)
    
    f = a.f
    
    a.i += 1
    autoTester.check (f ())
    
    a.i += 10
    autoTester.check (f ())
    
    a.i += a.i
    autoTester.check (f ())

4.45. Truthyness: optional Python-style evaluation of truthyness, falsyness and non-empty container selection

Testlet: truthyness
from org.transcrypt.stubs.browser import __pragma__

__pragma__ ('tconv')

def run (autoTester):
    autoTester.check (len ({1:2}))

    autoTester.check ('Select nonemtpy container, if any<br>')

    autoTester.check ((0) or (1, 2, 3))
    autoTester.check (() or (1, 2, 3))
    autoTester.check (() or ())
    
    autoTester.check ((-1) or (0) or (1, 2, 3))
    autoTester.check (() or (0) or (1, 2, 3))
    autoTester.check (() or () or (1, 2, 3))
    autoTester.check (() or () or ())
    
    autoTester.check ([0] or [1, 2, 3])
    autoTester.check ([] or [1, 2, 3])
    autoTester.check ([] or [])
    
    autoTester.check ([-1] or [0] or [1, 2, 3])
    autoTester.check ([] or [0] or [1, 2, 3])
    autoTester.check ([] or [] or [1, 2, 3])
    autoTester.check ([] or [] or [])
    
    autoTester.check ({0} or {1, 2, 3, 4})
    autoTester.check (set () or {1, 2, 3, 4})
    autoTester.check (set () or set ())
    
    autoTester.check ({-1} or {0} or {1, 2, 3, 5})
    autoTester.check (set () or {0} or {1, 2, 3, 6})
    autoTester.check (set () or set () or {1, 2, 3, 7})
    autoTester.check (set () or set () or set ())
    
    autoTester.check ({0:10} or {1:11, 2:12, 3:13})
    autoTester.check ({} or {1, 2, 3, 8})
    autoTester.check ({} or {})
    
    autoTester.check ({-1:-11} or {0:10} or {1:11, 2:12, 3:13})
    autoTester.check ({} or {0:10} or {1:11, 2:12, 3:13})
    autoTester.check ({} or {} or {1:11, 2:12, 3:13})
    autoTester.check ({} or {} or {})
    
    autoTester.check ('<br><br>')
    autoTester.check ('Boolean evaluations')
    for expression in (
        '<br> -- falsy -- <br>',
        (),
        [],
        set (),
        {},
        0,
        '',
        3 > 5,
        False,
        '<br> -- truthy -- <br>',
        (1, 2, 3),
        [1, 2, 3],
        {1, 2, 3},
        {'a': 1, 'b': 2, 'c': 3},
        3,
        'hello',
        5 > 3,
        True
    ):
        if expression in ('<br> -- falsy -- <br>', '<br> -- truthy -- <br>'):
            autoTester.check (expression)
        else:
            autoTester.check (expression, ' . . . ')
            autoTester.check ('operators')
            autoTester.check (not not expression)
            autoTester.check (not not (True and expression))
            autoTester.check (not not (False or expression))
            autoTester.check (not not (expression and True))
            autoTester.check (not not (expression and False))
            
            autoTester.check ('if')
            if expression:
                autoTester.check (True)
            else:
                autoTester.check (False)
                
            if expression or expression:
                autoTester.check (True)
            else:
                autoTester.check (False)
                
            if False:
                autoTester.check ('if')
            elif expression:
                autoTester.check ('elif')
            else:
                autoTester.check ('else')
                
            autoTester.check ('while')
            while expression:
                autoTester.check (True)
                break
                
            autoTester.check ('condex')
            autoTester.check (True if expression else False)
            
    if (0.0):
        autoTester.check ('0.0')
    elif (0.1):
        autoTester.check ('0.1')
    else:
        autoTester.check ('Shouldn\'t be here...')
        
    class A:
        pass
        
    class B:
        def __bool__ ( self):
            return False

    class C:
        def __bool__ (self):
            return True

        def __len__ (self):
            return 0

    class D:
        def __len__ (self):
            return 0

    class E:
        def __len__ (self):
            return 1

    autoTester.check ('instances of custom classes')
    autoTester.check (not not A ())
    autoTester.check (not not B ())
    autoTester.check (not not C ())
    autoTester.check (not not D ())
    autoTester.check (not not E ())
    

4.46. Tuple assignment: recursive and in for-headers using enumerate

Testlet: tuple_assignment
def run (autoTester):
    ((a, b), santa, [c, d], e) = ((1, 2), 'santa-claus', {3, 4}, 5)
    autoTester.check (a, b, c, d, e, santa)
    
    for i, x in enumerate ((0.5, 1.5, 2.5, 3.5)):
        autoTester.check (i, x)
    
    e, pi = 3.14, 2.74
    e, pi = pi, e
    autoTester.check (e, pi)
    
    def f ():
        return [(i, 2 * i) for i in range (7000, 10000, 1000)]
        
    def g ():
        return f
        
    [k, l], [m, n], (o, p) = g () ()
    
    autoTester.check (k, l, m, n, o, p)