contrib/check-commit

rebase: move destination computation in a revset

This is the first step toward making the "default destination" logic more clear
and unified. The revset is private because I'm happy to delay the bikeshedding until
after the clean up happened.

#!/usr/bin/env python
#
# Copyright 2014 Matt Mackall <[e-mail]>
#
# A tool/hook to run basic sanity checks on commits/patches for
# submission to Mercurial. Install by adding the following to your
# .hg/hgrc:
#
# [hooks]
# pretxncommit = contrib/check-commit
#
# The hook can be temporarily bypassed with:
#
# $ BYPASS= hg commit
#
# See also: http://mercurial.selenic.com/wiki/ContributingChanges

import re, sys, os

errors = [
    (r"[(]bc[)]", "(BC) needs to be uppercase"),
    (r"[(]issue \d\d\d", "no space allowed between issue and number"),
    (r"[(]bug(\d|\s)", "use (issueDDDD) instead of bug"),
    (r"^# User [^@\n]+$", "username is not an email address"),
    (r"^# .*\n(?!merge with )[^#]\S+[^:] ",
     "summary line doesn't start with 'topic: '"),
    (r"^# .*\n[A-Z][a-z]\S+", "don't capitalize summary lines"),
    (r"^# .*\n[^\n]*: *[A-Z][a-z]\S+", "don't capitalize summary lines"),
    (r"^# .*\n.*\.\s+$", "don't add trailing period on summary line"),
    (r"^# .*\n.{78,}", "summary line too long (limit is 78)"),
    (r"^\+\n \n", "adds double empty line"),
    (r"^ \n\+\n", "adds double empty line"),
    (r"^\+[ \t]+def [a-z]+_[a-z]", "adds a function with foo_bar naming"),
]

node = os.environ.get("HG_NODE")

if node:
    commit = os.popen("hg export %s" % node).read()
else:
    commit = sys.stdin.read()

exitcode = 0
for exp, msg in errors:
    m = re.search(exp, commit, re.MULTILINE)
    if m:
        pos = 0
        for n, l in enumerate(commit.splitlines(True)):
            pos += len(l)
            if pos >= m.end():
                print "%d: %s" % (n, msg)
                print " %s" % l[:-1]
                if "BYPASS" not in os.environ:
                    exitcode = 1
                break

sys.exit(exitcode)