Added simple test case for mmap on Unix; someone needs to write a

Win32 test case

Lib/test/test_mmap.py

@@ -0,0 +1,69 @@
+
+import mmap
+import string, os, re, sys
+
+PAGESIZE = mmap.PAGESIZE
+
+def test_unix():
+    "Test mmap module on Unix systems"
+    	
+    # Create an mmap'ed file
+    f = open('foo', 'w+')
+    
+    # Write 2 pages worth of data to the file
+    f.write('\0'* PAGESIZE)
+    f.write('foo')
+    f.write('\0'* (PAGESIZE-3) )
+    
+    m = mmap.mmap(f.fileno(), 2 * PAGESIZE)
+    f.close()
+    
+    # Simple sanity checks
+    print '  Position of foo:', string.find(m, 'foo') / float(PAGESIZE), 'pages'
+    assert string.find(m, 'foo') == PAGESIZE
+    
+    print '  Length of file:', len(m) / float(PAGESIZE), 'pages'
+    assert len(m) == 2*PAGESIZE
+
+    print '  Contents of byte 0:', repr(m[0])
+    assert m[0] == '\0'
+    print '  Contents of first 3 bytes:', repr(m[0:3])
+    assert m[0:3] == '\0\0\0'
+    
+    # Modify the file's content
+    print "\n  Modifying file's content..."
+    m[0] = '3'
+    m[PAGESIZE +3: PAGESIZE +3+3]='bar'
+    
+    # Check that the modification worked
+    print '  Contents of byte 0:', repr(m[0])
+    assert m[0] == '3'
+    print '  Contents of first 3 bytes:', repr(m[0:3])
+    assert m[0:3] == '3\0\0'
+    print '  Contents of second page:',  m[PAGESIZE-1 : PAGESIZE + 7]
+    assert m[PAGESIZE-1 : PAGESIZE + 7] == '\0foobar\0'
+    
+    m.flush()
+
+    # Test doing a regular expression match in an mmap'ed file
+    match=re.search('[A-Za-z]+', m)
+    if match == None:
+        print '  ERROR: regex match on mmap failed!'
+    else:
+        start, end = match.span(0)
+        length = end - start               
+
+        print '  Regex match on mmap (page start, length of match):',
+        print start / float(PAGESIZE), length
+        
+        assert start == PAGESIZE
+        assert end == PAGESIZE + 6
+        
+    print ' Test passed'
+
+# XXX need to write a test suite for Windows
+if sys.platform == 'win32':
+    pass
+else:
+    test_unix()
+