| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225 |
- import unittest
- import sys
- from io import StringIO
- from test import support
- NotDefined = object()
- # A dispatch table all 8 combinations of providing
- # sep, end, and file.
- # I use this machinery so that I'm not just passing default
- # values to print, I'm either passing or not passing in the
- # arguments.
- dispatch = {
- (False, False, False):
- lambda args, sep, end, file: print(*args),
- (False, False, True):
- lambda args, sep, end, file: print(file=file, *args),
- (False, True, False):
- lambda args, sep, end, file: print(end=end, *args),
- (False, True, True):
- lambda args, sep, end, file: print(end=end, file=file, *args),
- (True, False, False):
- lambda args, sep, end, file: print(sep=sep, *args),
- (True, False, True):
- lambda args, sep, end, file: print(sep=sep, file=file, *args),
- (True, True, False):
- lambda args, sep, end, file: print(sep=sep, end=end, *args),
- (True, True, True):
- lambda args, sep, end, file: print(sep=sep, end=end, file=file, *args),
- }
- # Class used to test __str__ and print
- class ClassWith__str__:
- def __init__(self, x):
- self.x = x
- def __str__(self):
- return self.x
- class TestPrint(unittest.TestCase):
- """Test correct operation of the print function."""
- def check(self, expected, args,
- sep=NotDefined, end=NotDefined, file=NotDefined):
- # Capture sys.stdout in a StringIO. Call print with args,
- # and with sep, end, and file, if they're defined. Result
- # must match expected.
- # Look up the actual function to call, based on if sep, end,
- # and file are defined.
- fn = dispatch[(sep is not NotDefined,
- end is not NotDefined,
- file is not NotDefined)]
- with support.captured_stdout() as t:
- fn(args, sep, end, file)
- self.assertEqual(t.getvalue(), expected)
- def test_print(self):
- def x(expected, args, sep=NotDefined, end=NotDefined):
- # Run the test 2 ways: not using file, and using
- # file directed to a StringIO.
- self.check(expected, args, sep=sep, end=end)
- # When writing to a file, stdout is expected to be empty
- o = StringIO()
- self.check('', args, sep=sep, end=end, file=o)
- # And o will contain the expected output
- self.assertEqual(o.getvalue(), expected)
- x('\n', ())
- x('a\n', ('a',))
- x('None\n', (None,))
- x('1 2\n', (1, 2))
- x('1 2\n', (1, ' ', 2))
- x('1*2\n', (1, 2), sep='*')
- x('1 s', (1, 's'), end='')
- x('a\nb\n', ('a', 'b'), sep='\n')
- x('1.01', (1.0, 1), sep='', end='')
- x('1*a*1.3+', (1, 'a', 1.3), sep='*', end='+')
- x('a\n\nb\n', ('a\n', 'b'), sep='\n')
- x('\0+ +\0\n', ('\0', ' ', '\0'), sep='+')
- x('a\n b\n', ('a\n', 'b'))
- x('a\n b\n', ('a\n', 'b'), sep=None)
- x('a\n b\n', ('a\n', 'b'), end=None)
- x('a\n b\n', ('a\n', 'b'), sep=None, end=None)
- x('*\n', (ClassWith__str__('*'),))
- x('abc 1\n', (ClassWith__str__('abc'), 1))
- # errors
- self.assertRaises(TypeError, print, '', sep=3)
- self.assertRaises(TypeError, print, '', end=3)
- self.assertRaises(AttributeError, print, '', file='')
- def test_print_flush(self):
- # operation of the flush flag
- class filelike:
- def __init__(self):
- self.written = ''
- self.flushed = 0
- def write(self, str):
- self.written += str
- def flush(self):
- self.flushed += 1
- f = filelike()
- print(1, file=f, end='', flush=True)
- print(2, file=f, end='', flush=True)
- print(3, file=f, flush=False)
- self.assertEqual(f.written, '123\n')
- self.assertEqual(f.flushed, 2)
- # ensure exceptions from flush are passed through
- class noflush:
- def write(self, str):
- pass
- def flush(self):
- raise RuntimeError
- self.assertRaises(RuntimeError, print, 1, file=noflush(), flush=True)
- class TestPy2MigrationHint(unittest.TestCase):
- """Test that correct hint is produced analogous to Python3 syntax,
- if print statement is executed as in Python 2.
- """
- def test_normal_string(self):
- python2_print_str = 'print "Hello World"'
- with self.assertRaises(SyntaxError) as context:
- exec(python2_print_str)
- self.assertIn("Missing parentheses in call to 'print'. Did you mean print(...)",
- str(context.exception))
- def test_string_with_soft_space(self):
- python2_print_str = 'print "Hello World",'
- with self.assertRaises(SyntaxError) as context:
- exec(python2_print_str)
- self.assertIn("Missing parentheses in call to 'print'. Did you mean print(...)",
- str(context.exception))
- def test_string_with_excessive_whitespace(self):
- python2_print_str = 'print "Hello World", '
- with self.assertRaises(SyntaxError) as context:
- exec(python2_print_str)
- self.assertIn("Missing parentheses in call to 'print'. Did you mean print(...)",
- str(context.exception))
- def test_string_with_leading_whitespace(self):
- python2_print_str = '''if 1:
- print "Hello World"
- '''
- with self.assertRaises(SyntaxError) as context:
- exec(python2_print_str)
- self.assertIn("Missing parentheses in call to 'print'. Did you mean print(...)",
- str(context.exception))
- # bpo-32685: Suggestions for print statement should be proper when
- # it is in the same line as the header of a compound statement
- # and/or followed by a semicolon
- def test_string_with_semicolon(self):
- python2_print_str = 'print p;'
- with self.assertRaises(SyntaxError) as context:
- exec(python2_print_str)
- self.assertIn("Missing parentheses in call to 'print'. Did you mean print(...)",
- str(context.exception))
- def test_string_in_loop_on_same_line(self):
- python2_print_str = 'for i in s: print i'
- with self.assertRaises(SyntaxError) as context:
- exec(python2_print_str)
- self.assertIn("Missing parentheses in call to 'print'. Did you mean print(...)",
- str(context.exception))
- def test_stream_redirection_hint_for_py2_migration(self):
- # Test correct hint produced for Py2 redirection syntax
- with self.assertRaises(TypeError) as context:
- print >> sys.stderr, "message"
- self.assertIn('Did you mean "print(<message>, '
- 'file=<output_stream>)"?', str(context.exception))
- # Test correct hint is produced in the case where RHS implements
- # __rrshift__ but returns NotImplemented
- with self.assertRaises(TypeError) as context:
- print >> 42
- self.assertIn('Did you mean "print(<message>, '
- 'file=<output_stream>)"?', str(context.exception))
- # Test stream redirection hint is specific to print
- with self.assertRaises(TypeError) as context:
- max >> sys.stderr
- self.assertNotIn('Did you mean ', str(context.exception))
- # Test stream redirection hint is specific to rshift
- with self.assertRaises(TypeError) as context:
- print << sys.stderr
- self.assertNotIn('Did you mean', str(context.exception))
- # Ensure right operand implementing rrshift still works
- class OverrideRRShift:
- def __rrshift__(self, lhs):
- return 42 # Force result independent of LHS
- self.assertEqual(print >> OverrideRRShift(), 42)
- if __name__ == "__main__":
- unittest.main()
|