Johnny Chen | 10dd7a4 | 2011-11-04 01:05:29 +0000 | [diff] [blame] | 1 | #!/usr/bin/env python |
| 2 | |
| 3 | """ |
| 4 | Greps and returns the first svn log entry containing a line matching the regular |
| 5 | expression pattern passed as the only arg. |
| 6 | |
| 7 | Example: |
| 8 | |
| 9 | svn log -v | grep-svn-log.py '^ D.+why_are_you_missing.h$' |
| 10 | """ |
| 11 | |
| 12 | import fileinput, re, sys, StringIO |
| 13 | |
| 14 | # Separator string for "svn log -v" output. |
| 15 | separator = '-' * 72 |
| 16 | |
| 17 | usage = """Usage: grep-svn-log.py line-pattern |
| 18 | Example: |
| 19 | svn log -v | grep-svn-log.py '^ D.+why_are_you_missing.h'""" |
| 20 | |
| 21 | class Log(StringIO.StringIO): |
| 22 | """Simple facade to keep track of the log content.""" |
| 23 | def __init__(self): |
| 24 | self.reset() |
| 25 | def add_line(self, a_line): |
| 26 | """Add a line to the content, if there is a previous line, commit it.""" |
| 27 | global separator |
| 28 | if self.prev_line != None: |
| 29 | print >> self, self.prev_line |
| 30 | self.prev_line = a_line |
| 31 | self.separator_added = (a_line == separator) |
| 32 | def del_line(self): |
| 33 | """Forget about the previous line, do not commit it.""" |
| 34 | self.prev_line = None |
| 35 | def reset(self): |
| 36 | """Forget about the previous lines entered.""" |
| 37 | StringIO.StringIO.__init__(self) |
| 38 | self.prev_line = None |
| 39 | def finish(self): |
| 40 | """Call this when you're finished with populating content.""" |
| 41 | if self.prev_line != None: |
| 42 | print >> self, self.prev_line |
| 43 | self.prev_line = None |
| 44 | |
| 45 | def grep(regexp): |
| 46 | # The log content to be written out once a match is found. |
| 47 | log = Log() |
| 48 | |
| 49 | LOOKING_FOR_MATCH = 0 |
| 50 | FOUND_LINE_MATCH = 1 |
| 51 | state = LOOKING_FOR_MATCH |
| 52 | |
| 53 | while 1: |
| 54 | line = sys.stdin.readline() |
| 55 | if not line: |
| 56 | return |
| 57 | line = line.splitlines()[0] |
| 58 | if state == FOUND_LINE_MATCH: |
| 59 | # At this state, we keep on accumulating lines until the separator |
| 60 | # is encountered. At which point, we can return the log content. |
| 61 | if line == separator: |
Johnny Chen | aa142bc | 2012-03-05 18:25:29 +0000 | [diff] [blame] | 62 | log.finish() |
Johnny Chen | 10dd7a4 | 2011-11-04 01:05:29 +0000 | [diff] [blame] | 63 | print log.getvalue() |
| 64 | return |
| 65 | log.add_line(line) |
| 66 | |
| 67 | elif state == LOOKING_FOR_MATCH: |
| 68 | if line == separator: |
| 69 | log.reset() |
| 70 | log.add_line(line) |
| 71 | # Update next state if necessary. |
| 72 | if regexp.search(line): |
| 73 | state = FOUND_LINE_MATCH |
| 74 | |
| 75 | def main(): |
| 76 | if len(sys.argv) != 2: |
| 77 | print usage |
| 78 | sys.exit(0) |
| 79 | |
| 80 | regexp = re.compile(sys.argv[1]) |
| 81 | grep(regexp) |
Johnny Chen | aa142bc | 2012-03-05 18:25:29 +0000 | [diff] [blame] | 82 | sys.stdin.close() |
Johnny Chen | 10dd7a4 | 2011-11-04 01:05:29 +0000 | [diff] [blame] | 83 | |
| 84 | if __name__ == '__main__': |
| 85 | main() |