check-config: mention the file and line of the error

I used this to more quickly track down a failing test-check-config.t issue
in another repo. I thought it might be useful more generally, so I'm sending
it out in case others think it's a worthwhile change.

contrib/check-config.py

@@ -1,139 +1,142 b''
 #!/usr/bin/env python
 #
 # check-config - a config flag documentation checker for Mercurial
 #
 # Copyright 2015 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import absolute_import, print_function
 import re
 import sys
 
 foundopts = {}
 documented = {}
 allowinconsistent = set()
 
 configre = re.compile(r'''
     # Function call
     ui\.config(?P<ctype>|int|bool|list)\(
         # First argument.
         ['"](?P<section>\S+)['"],\s*
         # Second argument
         ['"](?P<option>\S+)['"](,\s+
         (?:default=)?(?P<default>\S+?))?
     \)''', re.VERBOSE | re.MULTILINE)
 
 configwithre = re.compile('''
     ui\.config(?P<ctype>with)\(
         # First argument is callback function. This doesn't parse robustly
         # if it is e.g. a function call.
         [^,]+,\s*
         ['"](?P<section>\S+)['"],\s*
         ['"](?P<option>\S+)['"](,\s+
         (?:default=)?(?P<default>\S+?))?
     \)''', re.VERBOSE | re.MULTILINE)
 
 configpartialre = (r"""ui\.config""")
 
 ignorere = re.compile(r'''
     \#\s(?P<reason>internal|experimental|deprecated|developer|inconsistent)\s
     config:\s(?P<config>\S+\.\S+)$
     ''', re.VERBOSE | re.MULTILINE)
 
 def main(args):
     for f in args:
         sect = ''
         prevname = ''
         confsect = ''
         carryover = ''
+        linenum = 0
         for l in open(f):
+            linenum += 1
 
             # check topic-like bits
             m = re.match('\s*``(\S+)``', l)
             if m:
                 prevname = m.group(1)
             if re.match('^\s*-+$', l):
                 sect = prevname
                 prevname = ''
 
             if sect and prevname:
                 name = sect + '.' + prevname
                 documented[name] = 1
 
             # check docstring bits
             m = re.match(r'^\s+\[(\S+)\]', l)
             if m:
                 confsect = m.group(1)
                 continue
             m = re.match(r'^\s+(?:#\s*)?(\S+) = ', l)
             if m:
                 name = confsect + '.' + m.group(1)
                 documented[name] = 1
 
             # like the bugzilla extension
             m = re.match(r'^\s*(\S+\.\S+)$', l)
             if m:
                 documented[m.group(1)] = 1
 
             # like convert
             m = re.match(r'^\s*:(\S+\.\S+):\s+', l)
             if m:
                 documented[m.group(1)] = 1
 
             # quoted in help or docstrings
             m = re.match(r'.*?``(\S+\.\S+)``', l)
             if m:
                 documented[m.group(1)] = 1
 
             # look for ignore markers
             m = ignorere.search(l)
             if m:
                 if m.group('reason') == 'inconsistent':
                     allowinconsistent.add(m.group('config'))
                 else:
                     documented[m.group('config')] = 1
 
             # look for code-like bits
             line = carryover + l
             m = configre.search(line) or configwithre.search(line)
             if m:
                 ctype = m.group('ctype')
                 if not ctype:
                     ctype = 'str'
                 name = m.group('section') + "." + m.group('option')
                 default = m.group('default')
                 if default in (None, 'False', 'None', '0', '[]', '""', "''"):
                     default = ''
                 if re.match('[a-z.]+$', default):
                     default = '<variable>'
                 if (name in foundopts and (ctype, default) != foundopts[name]
                     and name not in allowinconsistent):
-                    print(l)
+                    print(l.rstrip())
                     print("conflict on %s: %r != %r" % (name, (ctype, default),
                                                         foundopts[name]))
+                    print("at %s:%d:" % (f, linenum))
                 foundopts[name] = (ctype, default)
                 carryover = ''
             else:
                 m = re.search(configpartialre, line)
                 if m:
                     carryover = line
                 else:
                     carryover = ''
 
     for name in sorted(foundopts):
         if name not in documented:
             if not (name.startswith("devel.") or
                     name.startswith("experimental.") or
                     name.startswith("debug.")):
                 ctype, default = foundopts[name]
                 if default:
                     default = ' [%s]' % default
                 print("undocumented: %s (%s)%s" % (name, ctype, default))
 
 if __name__ == "__main__":
     if len(sys.argv) > 1:
         sys.exit(main(sys.argv[1:]))
     else:
         sys.exit(main([l.rstrip() for l in sys.stdin]))

tests/test-check-config.t

@@ -1,47 +1,47 b''
 #require test-repo
 
   $ . "$TESTDIR/helpers-testrepo.sh"
 
 Sanity check check-config.py
 
   $ cat > testfile.py << EOF
   > # Good
   > foo = ui.config('ui', 'username')
   > # Missing
   > foo = ui.config('ui', 'doesnotexist')
   > # Missing different type
   > foo = ui.configint('ui', 'missingint')
   > # Missing with default value
   > foo = ui.configbool('ui', 'missingbool1', default=True)
   > foo = ui.configbool('ui', 'missingbool2', False)
   > # Inconsistent values for defaults.
   > foo = ui.configint('ui', 'intdefault', default=1)
   > foo = ui.configint('ui', 'intdefault', default=42)
   > # Can suppress inconsistent value error
   > foo = ui.configint('ui', 'intdefault2', default=1)
   > # inconsistent config: ui.intdefault2
   > foo = ui.configint('ui', 'intdefault2', default=42)
   > EOF
 
   $ cat > files << EOF
   > mercurial/help/config.txt
   > $TESTTMP/testfile.py
   > EOF
 
   $ cd "$TESTDIR"/..
 
   $ $PYTHON contrib/check-config.py < $TESTTMP/files
   foo = ui.configint('ui', 'intdefault', default=42)
-  
   conflict on ui.intdefault: ('int', '42') != ('int', '1')
+  at $TESTTMP/testfile.py:12: (glob)
   undocumented: ui.doesnotexist (str)
   undocumented: ui.intdefault (int) [42]
   undocumented: ui.intdefault2 (int) [42]
   undocumented: ui.missingbool1 (bool) [True]
   undocumented: ui.missingbool2 (bool)
   undocumented: ui.missingint (int)
 
 New errors are not allowed. Warnings are strongly discouraged.
 
   $ testrepohg files "set:(**.py or **.txt) - tests/**" | sed 's|\\|/|g' |
   >   $PYTHON contrib/check-config.py