tests/filterpyflakes.py

revert: extract actual revert in its own function

With this small refactoring, the computation of the action to perform and the
actual change to the disk happen in different function. This allows extension to
wrap the later in case of need. The initial motivation is the `remotefilelog`
extension that need to prefetch all the file content to be checked out.

#!/usr/bin/env python

# Filter output by pyflakes to control which warnings we check

import sys, re, os

def makekey(typeandline):
    """
    for sorting lines by: msgtype, path/to/file, lineno, message

    typeandline is a sequence of a message type and the entire message line
    the message line format is path/to/file:line: message

    >>> makekey((3, 'example.py:36: any message'))
    (3, 'example.py', 36, ' any message')
    >>> makekey((7, 'path/to/file.py:68: dummy message'))
    (7, 'path/to/file.py', 68, ' dummy message')
    >>> makekey((2, 'fn:88: m')) > makekey((2, 'fn:9: m'))
    True
    """

    msgtype, line = typeandline
    fname, line, message = line.split(":", 2)
    # line as int for ordering 9 before 88
    return msgtype, fname, int(line), message


lines = []
for line in sys.stdin:
    # We whitelist tests (see more messages in pyflakes.messages)
    pats = [
            r"imported but unused",
            r"local variable '.*' is assigned to but never used",
            r"unable to detect undefined names",
           ]
    for msgtype, pat in enumerate(pats):
        if re.search(pat, line):
            break # pattern matches
    else:
        continue # no pattern matched, next line
    fn = line.split(':', 1)[0]
    f = open(os.path.join(os.path.dirname(os.path.dirname(__file__)), fn))
    data = f.read()
    f.close()
    if 'no-' 'check-code' in data:
        continue
    lines.append((msgtype, line))

for msgtype, line in sorted(lines, key=makekey):
    sys.stdout.write(line)
print