1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/en/examples/ch09/check_whitespace.py.lst	Tue Nov 24 22:16:48 2009 -0500
     1.3 @@ -0,0 +1,47 @@
     1.4 +#!/usr/bin/env python
     1.5 +#
     1.6 +# save as .hg/check_whitespace.py and make executable
     1.7 +
     1.8 +import re
     1.9 +
    1.10 +def trailing_whitespace(difflines):
    1.11 +    # 
    1.12 +    linenum, header = 0, False
    1.13 +
    1.14 +    for line in difflines:
    1.15 +        if header:
    1.16 +            # remember the name of the file that this diff affects
    1.17 +            m = re.match(r'(?:---|\+\+\+) ([^\t]+)', line)
    1.18 +            if m and m.group(1) != '/dev/null':
    1.19 +                filename = m.group(1).split('/', 1)[-1]
    1.20 +            if line.startswith('+++ '):
    1.21 +                header = False
    1.22 +            continue
    1.23 +        if line.startswith('diff '):
    1.24 +            header = True
    1.25 +            continue
    1.26 +        # hunk header - save the line number
    1.27 +        m = re.match(r'@@ -\d+,\d+ \+(\d+),', line)
    1.28 +        if m:
    1.29 +            linenum = int(m.group(1))
    1.30 +            continue
    1.31 +        # hunk body - check for an added line with trailing whitespace
    1.32 +        m = re.match(r'\+.*\s$', line)
    1.33 +        if m:
    1.34 +            yield filename, linenum
    1.35 +        if line and line[0] in ' +':
    1.36 +            linenum += 1
    1.37 +
    1.38 +if __name__ == '__main__':
    1.39 +    import os, sys
    1.40 +    
    1.41 +    added = 0
    1.42 +    for filename, linenum in trailing_whitespace(os.popen('hg export tip')):
    1.43 +        print >> sys.stderr, ('%s, line %d: trailing whitespace added' %
    1.44 +                              (filename, linenum))
    1.45 +        added += 1
    1.46 +    if added:
    1.47 +        # save the commit message so we don't need to retype it
    1.48 +        os.system('hg tip --template "{desc}" > .hg/commit.save')
    1.49 +        print >> sys.stderr, 'commit message saved to .hg/commit.save'
    1.50 +        sys.exit(1)