contrib/check-commit

hgweb: extract changelist entry generation into own function

I want to supplement changelist entries (used by shortlog and changelog
endpoints) with custom metadata from an extension. i.e. I have extra
per-changeset metadata that I wish to make available to templates so it
can be rendered on hgweb.

To facilitate this, I've extracted the logic for creating a changeset
data structure into its own function, where it can be wrapped by
extensions.

Ideally, hgweb would use the same templater as the command line and have
full access to templatekw.keywords. But that's a lot of work. This patch
gets us some of the benefit without all the work.

Many other hgweb commands could benefit from similar refactorings. I'm
going to wait to see how this patch is received before I go crazy on
extracting inline functions.

#!/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", "use (issueDDDD) instead of bug"),
    (r"^# User [^@\n]+$", "username is not an email address"),
    (r"^# .*\n(?!merge with )[^#]\S+[^:] ",
     "summary line doesn't start with 'topic: '"),
    (r"^# .*\n[A-Z][a-z]\S+", "don't capitalize summary lines"),
    (r"^# .*\n.*\.\s+$", "don't add trailing period on summary line"),
    (r"^# .*\n.{78,}", "summary line too long"),
    (r"^\+\n \n", "adds double empty line"),
    (r"\+\s+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)