145 lines
4.6 KiB
Python
145 lines
4.6 KiB
Python
"""Test correct operation of the print function.
|
|
"""
|
|
|
|
# In 2.6, this gives us the behavior we want. In 3.0, it has
|
|
# no function, but it still must parse correctly.
|
|
from __future__ import print_function
|
|
|
|
import unittest
|
|
from test import support
|
|
|
|
try:
|
|
# 3.x
|
|
from io import StringIO
|
|
except ImportError:
|
|
# 2.x
|
|
from StringIO import StringIO
|
|
|
|
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):
|
|
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))
|
|
|
|
# # 2.x unicode tests
|
|
# x(u'1 2\n', ('1', u'2'))
|
|
# x(u'u\1234\n', (u'u\1234',))
|
|
# x(u' abc 1\n', (' ', ClassWith__str__(u'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)
|
|
|
|
def test_main():
|
|
support.run_unittest(TestPrint)
|
|
|
|
if __name__ == "__main__":
|
|
test_main()
|