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Jython is an implementation of the high-level, dynamic, object-oriented language Python written in 100% Pure Java, and seamlessly integrated with the Java platform. It thus allows you to run Python on any Java platform.

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#XXX: The details of the exception messages have been excluded.
#     This should be revisited, since matching some of these
#     exception messages is sensible.
"""This module tests SyntaxErrors.

Here's an example of the sort of thing that is tested.

>>> def f(x):
...     global x
Traceback (most recent call last):
SyntaxError: name 'x' is local and global

The tests are all raise SyntaxErrors.  They were created by checking
each C call that raises SyntaxError.  There are several modules that
raise these exceptions-- ast.c, compile.c, future.c, pythonrun.c, and
symtable.c.

The parser itself outlaws a lot of invalid syntax.  None of these
errors are tested here at the moment.  We should add some tests; since
there are infinitely many programs with invalid syntax, we would need
to be judicious in selecting some.

The compiler generates a synthetic module name for code executed by
doctest.  Since all the code comes from the same module, a suffix like
[1] is appended to the module name, As a consequence, changing the
order of tests in this module means renumbering all the errors after
it.  (Maybe we should enable the ellipsis option for these tests.)

In ast.c, syntax errors are raised by calling ast_error().

Errors from set_context():

TODO(jhylton): "assignment to None" is inconsistent with other messages

#XXX: None as a dotted name is specifically allowed in Jython for Java compatibility.
#>>> obj.None = 1
#Traceback (most recent call last):
#SyntaxError: assignment to None (, line 1)

>>> None = 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: assignment to None (, line 1)

It's a syntax error to assign to the empty tuple.  Why isn't it an
error to assign to the empty list?  It will always raise some error at
runtime.

>>> () = 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't assign to () (, line 1)

>>> f() = 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't assign to function call (, line 1)

>>> del f() #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't delete function call (, line 1)

>>> a + 1 = 2 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't assign to operator (, line 1)

>>> (x for x in x) = 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't assign to generator expression (, line 1)

>>> 1 = 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't assign to literal (, line 1)

>>> "abc" = 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't assign to literal (, line 1)

>>> `1` = 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't assign to repr (, line 1)

If the left-hand side of an assignment is a list or tuple, an illegal
expression inside that contain should still cause a syntax error.
This test just checks a couple of cases rather than enumerating all of
them.

>>> (a, "b", c) = (1, 2, 3) #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't assign to literal (, line 1)

>>> [a, b, c + 1] = [1, 2, 3] #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't assign to operator (, line 1)

>>> a if 1 else b = 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: can't assign to conditional expression (, line 1)

From compiler_complex_args():

>>> def f(None=1): #doctest: +IGNORE_EXCEPTION_DETAIL
...     pass
Traceback (most recent call last):
SyntaxError: assignment to None (, line 1)


From ast_for_arguments():

>>> def f(x, y=1, z): #doctest: +IGNORE_EXCEPTION_DETAIL
...     pass
Traceback (most recent call last):
SyntaxError: non-default argument follows default argument (, line 1)

>>> def f(x, None): #doctest: +IGNORE_EXCEPTION_DETAIL
...     pass
Traceback (most recent call last):
SyntaxError: assignment to None (, line 1)

>>> def f(*None): #doctest: +IGNORE_EXCEPTION_DETAIL
...     pass
Traceback (most recent call last):
SyntaxError: assignment to None (, line 1)

>>> def f(**None): #doctest: +IGNORE_EXCEPTION_DETAIL
...     pass
Traceback (most recent call last):
SyntaxError: assignment to None (, line 1)


From ast_for_funcdef(): #doctest: +IGNORE_EXCEPTION_DETAIL

>>> def None(x): #doctest: +IGNORE_EXCEPTION_DETAIL
...     pass
Traceback (most recent call last):
SyntaxError: assignment to None (, line 1)


From ast_for_call():

>>> def f(it, *varargs):
...     return list(it)
>>> L = range(10)
>>> f(x for x in L)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> f(x for x in L, 1) #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: Generator expression must be parenthesized if not sole argument (, line 1)
>>> f((x for x in L), 1)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

### XXX: commented out -- jython lacks this limit -- should it have it?
#>>> f(i0,  i1,  i2,  i3,  i4,  i5,  i6,  i7,  i8,  i9,  i10,  i11,
#...   i12,  i13,  i14,  i15,  i16,  i17,  i18,  i19,  i20,  i21,  i22,
#...   i23,  i24,  i25,  i26,  i27,  i28,  i29,  i30,  i31,  i32,  i33,
#...   i34,  i35,  i36,  i37,  i38,  i39,  i40,  i41,  i42,  i43,  i44,
#...   i45,  i46,  i47,  i48,  i49,  i50,  i51,  i52,  i53,  i54,  i55,
#...   i56,  i57,  i58,  i59,  i60,  i61,  i62,  i63,  i64,  i65,  i66,
#...   i67,  i68,  i69,  i70,  i71,  i72,  i73,  i74,  i75,  i76,  i77,
#...   i78,  i79,  i80,  i81,  i82,  i83,  i84,  i85,  i86,  i87,  i88,
#...   i89,  i90,  i91,  i92,  i93,  i94,  i95,  i96,  i97,  i98,  i99,
#...   i100,  i101,  i102,  i103,  i104,  i105,  i106,  i107,  i108,
#...   i109,  i110,  i111,  i112,  i113,  i114,  i115,  i116,  i117,
#...   i118,  i119,  i120,  i121,  i122,  i123,  i124,  i125,  i126,
#...   i127,  i128,  i129,  i130,  i131,  i132,  i133,  i134,  i135,
#...   i136,  i137,  i138,  i139,  i140,  i141,  i142,  i143,  i144,
#...   i145,  i146,  i147,  i148,  i149,  i150,  i151,  i152,  i153,
#...   i154,  i155,  i156,  i157,  i158,  i159,  i160,  i161,  i162,
#...   i163,  i164,  i165,  i166,  i167,  i168,  i169,  i170,  i171,
#...   i172,  i173,  i174,  i175,  i176,  i177,  i178,  i179,  i180,
#...   i181,  i182,  i183,  i184,  i185,  i186,  i187,  i188,  i189,
#...   i190,  i191,  i192,  i193,  i194,  i195,  i196,  i197,  i198,
#...   i199,  i200,  i201,  i202,  i203,  i204,  i205,  i206,  i207,
#...   i208,  i209,  i210,  i211,  i212,  i213,  i214,  i215,  i216,
#...   i217,  i218,  i219,  i220,  i221,  i222,  i223,  i224,  i225,
#...   i226,  i227,  i228,  i229,  i230,  i231,  i232,  i233,  i234,
#...   i235,  i236,  i237,  i238,  i239,  i240,  i241,  i242,  i243,
#...   i244,  i245,  i246,  i247,  i248,  i249,  i250,  i251,  i252,
#...   i253,  i254,  i255)
#Traceback (most recent call last):
#SyntaxError: more than 255 arguments (, line 1)

The actual error cases counts positional arguments, keyword arguments,
and generator expression arguments separately.  This test combines the
three.

### XXX: commented out -- jython lacks this limit -- should it have it?
#>>> f(i0,  i1,  i2,  i3,  i4,  i5,  i6,  i7,  i8,  i9,  i10,  i11,
#...   i12,  i13,  i14,  i15,  i16,  i17,  i18,  i19,  i20,  i21,  i22,
#...   i23,  i24,  i25,  i26,  i27,  i28,  i29,  i30,  i31,  i32,  i33,
#...   i34,  i35,  i36,  i37,  i38,  i39,  i40,  i41,  i42,  i43,  i44,
#...   i45,  i46,  i47,  i48,  i49,  i50,  i51,  i52,  i53,  i54,  i55,
#...   i56,  i57,  i58,  i59,  i60,  i61,  i62,  i63,  i64,  i65,  i66,
#...   i67,  i68,  i69,  i70,  i71,  i72,  i73,  i74,  i75,  i76,  i77,
#...   i78,  i79,  i80,  i81,  i82,  i83,  i84,  i85,  i86,  i87,  i88,
#...   i89,  i90,  i91,  i92,  i93,  i94,  i95,  i96,  i97,  i98,  i99,
#...   i100,  i101,  i102,  i103,  i104,  i105,  i106,  i107,  i108,
#...   i109,  i110,  i111,  i112,  i113,  i114,  i115,  i116,  i117,
#...   i118,  i119,  i120,  i121,  i122,  i123,  i124,  i125,  i126,
#...   i127,  i128,  i129,  i130,  i131,  i132,  i133,  i134,  i135,
#...   i136,  i137,  i138,  i139,  i140,  i141,  i142,  i143,  i144,
#...   i145,  i146,  i147,  i148,  i149,  i150,  i151,  i152,  i153,
#...   i154,  i155,  i156,  i157,  i158,  i159,  i160,  i161,  i162,
#...   i163,  i164,  i165,  i166,  i167,  i168,  i169,  i170,  i171,
#...   i172,  i173,  i174,  i175,  i176,  i177,  i178,  i179,  i180,
#...   i181,  i182,  i183,  i184,  i185,  i186,  i187,  i188,  i189,
#...   i190,  i191,  i192,  i193,  i194,  i195,  i196,  i197,  i198,
#...   i199,  i200,  i201,  i202,  i203,  i204,  i205,  i206,  i207,
#...   i208,  i209,  i210,  i211,  i212,  i213,  i214,  i215,  i216,
#...   i217,  i218,  i219,  i220,  i221,  i222,  i223,  i224,  i225,
#...   i226,  i227,  i228,  i229,  i230,  i231,  i232,  i233,  i234,
#...   i235, i236,  i237,  i238,  i239,  i240,  i241,  i242,  i243,
#...   (x for x in i244),  i245,  i246,  i247,  i248,  i249,  i250,  i251,
#...    i252=1, i253=1,  i254=1,  i255=1)
#Traceback (most recent call last):
#SyntaxError: more than 255 arguments (, line 1)

>>> f(lambda x: x[0] = 3) #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: lambda cannot contain assignment (, line 1)

The grammar accepts any test (basically, any expression) in the
keyword slot of a call site.  Test a few different options.

>>> f(x()=2) #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: keyword can't be an expression (, line 1)
>>> f(a or b=1) #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: keyword can't be an expression (, line 1)
>>> f(x.y=1) #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: keyword can't be an expression (, line 1)


From ast_for_expr_stmt():

>>> (x for x in x) += 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: augmented assignment to generator expression not possible (, line 1)
>>> None += 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: assignment to None (, line 1)
>>> f() += 1 #doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
SyntaxError: illegal expression for augmented assignment (, line 1)


Test continue in finally in weird combinations.

continue in for loop under finally shouuld be ok.

    >>> def test():
    ...     try:
    ...         pass
    ...     finally:
    ...         for abc in range(10):
    ...             continue
    ...     print abc
    >>> test()
    9

Start simple, a continue in a finally should not be allowed.

    >>> def test(): #doctest: +IGNORE_EXCEPTION_DETAIL
    ...    for abc in range(10):
    ...        try:
    ...            pass
    ...        finally:
    ...            continue
    ...
    Traceback (most recent call last):
      ...
    SyntaxError: 'continue' not supported inside 'finally' clause (, line 6)

This is essentially a continue in a finally which should not be allowed.

    >>> def test(): #doctest: +IGNORE_EXCEPTION_DETAIL
    ...    for abc in range(10):
    ...        try:
    ...            pass
    ...        finally:
    ...            try:
    ...                continue
    ...            except:
    ...                pass
    Traceback (most recent call last):
      ...
    SyntaxError: 'continue' not supported inside 'finally' clause (, line 7)

    >>> def foo(): #doctest: +IGNORE_EXCEPTION_DETAIL
    ...   try:
    ...     pass
    ...   finally:
    ...     continue
    Traceback (most recent call last):
      ...
    SyntaxError: 'continue' not supported inside 'finally' clause (, line 5)

    >>> def foo(): #doctest: +IGNORE_EXCEPTION_DETAIL
    ...   for a in ():
    ...     try: pass
    ...     finally: continue
    Traceback (most recent call last):
      ...
    SyntaxError: 'continue' not supported inside 'finally' clause (, line 4)

    >>> def foo(): #doctest: +IGNORE_EXCEPTION_DETAIL
    ...  for a in ():
    ...   try: pass
    ...   finally:
    ...    try:
    ...     continue
    ...    finally: pass
    Traceback (most recent call last):
      ...
    SyntaxError: 'continue' not supported inside 'finally' clause (, line 6)

    >>> def foo(): #doctest: +IGNORE_EXCEPTION_DETAIL
    ...  for a in ():
    ...   try: pass
    ...   finally:
    ...    try:
    ...     pass
    ...    except:
    ...     continue
    Traceback (most recent call last):
      ...
    SyntaxError: 'continue' not supported inside 'finally' clause (, line 8)

There is one test for a break that is not in a loop.  The compiler
uses a single data structure to keep track of try-finally and loops,
so we need to be sure that a break is actually inside a loop.  If it
isn't, there should be a syntax error.

   >>> try: #doctest: +IGNORE_EXCEPTION_DETAIL
   ...     print 1
   ...     break
   ...     print 2
   ... finally:
   ...     print 3
   Traceback (most recent call last):
     ...
   SyntaxError: 'break' outside loop (, line 3)

This should probably raise a better error than a SystemError (or none at all).
In 2.5 there was a missing exception and an assert was triggered in a debug
build.  The number of blocks must be greater than CO_MAXBLOCKS.  SF #1565514

### XXX: commented out -- jython lacks this limit -- should it have it?
#   >>> while 1:
#   ...  while 2:
#   ...   while 3:
#   ...    while 4:
#   ...     while 5:
#   ...      while 6:
#   ...       while 8:
#   ...        while 9:
#   ...         while 10:
#   ...          while 11:
#   ...           while 12:
#   ...            while 13:
#   ...             while 14:
#   ...              while 15:
#   ...               while 16:
#   ...                while 17:
#   ...                 while 18:
#   ...                  while 19:
#   ...                   while 20:
#   ...                    while 21:
#   ...                     while 22:
#   ...                      break
#   Traceback (most recent call last):
#     ...
#   SystemError: too many statically nested blocks

This tests assignment-context; there was a bug in Python 2.5 where compiling
a complex 'if' (one with 'elif') would fail to notice an invalid suite,
leading to spurious errors.

   >>> if 1: #doctest: +IGNORE_EXCEPTION_DETAIL
   ...   x() = 1
   ... elif 1:
   ...   pass
   Traceback (most recent call last):
     ...
   SyntaxError: can't assign to function call (, line 2)

   >>> if 1: #doctest: +IGNORE_EXCEPTION_DETAIL
   ...   pass
   ... elif 1:
   ...   x() = 1
   Traceback (most recent call last):
     ...
   SyntaxError: can't assign to function call (, line 4)

   >>> if 1: #doctest: +IGNORE_EXCEPTION_DETAIL
   ...   x() = 1
   ... elif 1:
   ...   pass
   ... else:
   ...   pass
   Traceback (most recent call last):
     ...
   SyntaxError: can't assign to function call (, line 2)

   >>> if 1: #doctest: +IGNORE_EXCEPTION_DETAIL
   ...   pass
   ... elif 1:
   ...   x() = 1
   ... else:
   ...   pass
   Traceback (most recent call last):
     ...
   SyntaxError: can't assign to function call (, line 4)

   >>> if 1: #doctest: +IGNORE_EXCEPTION_DETAIL
   ...   pass
   ... elif 1:
   ...   pass
   ... else:
   ...   x() = 1
   Traceback (most recent call last):
     ...
   SyntaxError: can't assign to function call (, line 6)

"""

import re
import unittest
import warnings

from test import test_support

class SyntaxTestCase(unittest.TestCase):

    def _check_error(self, code, errtext=None,
                     filename="", mode="exec", subclass=None):
        """Check that compiling code raises SyntaxError with errtext.

        errtest is a regular expression that must be present in the
        test of the exception raised.  If subclass is specified it
        is the expected subclass of SyntaxError (e.g. IndentationError).

        XXX: Made errtext optional, since the exact wording of exceptions
             is implementation dependant.
        """
        try:
            compile(code, filename, mode)
        except SyntaxError, err:
            if subclass and not isinstance(err, subclass):
                self.fail("SyntaxError is not a %s" % subclass.__name__)
            if errtext is not None:
                mo = re.search(errtext, str(err))
                if mo is None:
                    self.fail("SyntaxError did not contain '%r'" % (errtext,))
        else:
            self.fail("compile() did not raise SyntaxError")

    def test_assign_call(self):
        self._check_error("f() = 1", "assign")

    def test_assign_del(self):
        self._check_error("del f()", "delete")

    def test_global_err_then_warn(self):
        # Bug tickler:  The SyntaxError raised for one global statement
        # shouldn't be clobbered by a SyntaxWarning issued for a later one.
        source = re.sub('(?m)^ *:', '', """\
            :def error(a):
            :    global a  # SyntaxError
            :def warning():
            :    b = 1
            :    global b  # SyntaxWarning
            :""")
        warnings.filterwarnings(action='ignore', category=SyntaxWarning)
        self._check_error(source, "global")
        warnings.filters.pop(0)

    def test_break_outside_loop(self):
        self._check_error("break", "outside loop")

    def test_delete_deref(self):
        source = re.sub('(?m)^ *:', '', """\
            :def foo(x):
            :  def bar():
            :    print x
            :  del x
            :""")
        self._check_error(source, "nested scope")

    def test_unexpected_indent(self):
        if test_support.is_jython:
            self._check_error("foo()\n bar()\n")
        else:
            self._check_error("foo()\n bar()\n", "unexpected indent",
                              subclass=IndentationError)

    def test_no_indent(self):
        if test_support.is_jython:
            self._check_error("if 1:\nfoo()")
        else:
            self._check_error("if 1:\nfoo()", "expected an indented block",
                              subclass=IndentationError)

    def test_bad_outdent(self):
        self._check_error("if 1:\n  foo()\n bar()",
                          "unindent does not match .* level",
                          subclass=IndentationError)

    def test_kwargs_last(self):
        if test_support.is_jython:
            self._check_error("int(base=10, '2')")
        else:
            self._check_error("int(base=10, '2')", "non-keyword arg")

def test_main():
    test_support.run_unittest(SyntaxTestCase)
    from test import test_syntax
    test_support.run_doctest(test_syntax, verbosity=True)

if __name__ == "__main__":
    test_main()




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