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			60 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			60 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
from test_support import verify, TestFailed, TESTFN
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# Simple test to ensure that optimizations in fileobject.c deliver
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# the expected results.  For best testing, run this under a debug-build
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# Python too (to exercise asserts in the C code).
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# Repeat string 'pattern' as often as needed to reach total length
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# 'length'.  Then call try_one with that string, a string one larger
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# than that, and a string one smaller than that.  The main driver
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# feeds this all small sizes and various powers of 2, so we exercise
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# all likely stdio buffer sizes, and "off by one" errors on both
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# sides.
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def drive_one(pattern, length):
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    q, r = divmod(length, len(pattern))
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    teststring = pattern * q + pattern[:r]
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    verify(len(teststring) == length)
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    try_one(teststring)
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    try_one(teststring + "x")
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    try_one(teststring[:-1])
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# Write s + "\n" + s to file, then open it and ensure that successive
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# .readline()s deliver what we wrote.
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def try_one(s):
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    # Since C doesn't guarantee we can write/read arbitrary bytes in text
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    # files, use binary mode.
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    f = open(TESTFN, "wb")
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    # write once with \n and once without
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    f.write(s)
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    f.write("\n")
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    f.write(s)
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    f.close()
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    f = open(TESTFN, "rb")
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    line = f.readline()
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    if line != s + "\n":
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        raise TestFailed("Expected %r got %r" % (s + "\n", line))
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    line = f.readline()
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    if line != s:
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        raise TestFailed("Expected %r got %r" % (s, line))
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    line = f.readline()
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    if line:
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        raise TestFailed("Expected EOF but got %r" % line)
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    f.close()
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# A pattern with prime length, to avoid simple relationships with
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# stdio buffer sizes.
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primepat = "1234567890\00\01\02\03\04\05\06"
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nullpat = "\0" * 1000
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try:
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    for size in range(1, 257) + [512, 1000, 1024, 2048, 4096, 8192, 10000,
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                      16384, 32768, 65536, 1000000]:
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        drive_one(primepat, size)
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        drive_one(nullpat, size)
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finally:
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    try:
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        import os
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        os.unlink(TESTFN)
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    except:
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        pass
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