ignore: refactor file read into a function

This refactors the ignore file reading code into a function so that in a future
patch we can make it recursive.

mercurial/ignore.py

@@ -1,113 +1,119 b''
 # ignore.py - ignored file handling for mercurial
 #
 # Copyright 2007 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 i18n import _
 import util, match
 import re
 
 _commentre = None
 
 def ignorepats(lines):
     '''parse lines (iterable) of .hgignore text, returning a tuple of
     (patterns, parse errors). These patterns should be given to compile()
     to be validated and converted into a match function.'''
     syntaxes = {'re': 'relre:', 'regexp': 'relre:', 'glob': 'relglob:'}
     syntax = 'relre:'
     patterns = []
     warnings = []
 
     for line in lines:
         if "#" in line:
             global _commentre
             if not _commentre:
                 _commentre = re.compile(r'((^|[^\\])(\\\\)*)#.*')
             # remove comments prefixed by an even number of escapes
             line = _commentre.sub(r'\1', line)
             # fixup properly escaped comments that survived the above
             line = line.replace("\\#", "#")
         line = line.rstrip()
         if not line:
             continue
 
         if line.startswith('syntax:'):
             s = line[7:].strip()
             try:
                 syntax = syntaxes[s]
             except KeyError:
                 warnings.append(_("ignoring invalid syntax '%s'") % s)
             continue
         pat = syntax + line
         for s, rels in syntaxes.iteritems():
             if line.startswith(rels):
                 pat = line
                 break
             elif line.startswith(s+':'):
                 pat = rels + line[len(s) + 1:]
                 break
         patterns.append(pat)
 
     return patterns, warnings
 
+def readignorefile(filepath, warn, skipwarning=False):
+    try:
+        pats = []
+        fp = open(filepath)
+        pats, warnings = ignorepats(fp)
+        fp.close()
+        for warning in warnings:
+            warn("%s: %s\n" % (filepath, warning))
+    except IOError, inst:
+        if not skipwarning:
+            warn(_("skipping unreadable ignore file '%s': %s\n") %
+                 (filepath, inst.strerror))
+    return pats
+
 def readpats(root, files, warn):
     '''return a dict mapping ignore-file-name to list-of-patterns'''
 
     pats = {}
     for f in files:
         if f in pats:
             continue
-        try:
-            pats[f] = []
-            fp = open(f)
-            pats[f], warnings = ignorepats(fp)
-            fp.close()
-            for warning in warnings:
-                warn("%s: %s\n" % (f, warning))
-        except IOError, inst:
-            if f != files[0]:
-                warn(_("skipping unreadable ignore file '%s': %s\n") %
-                     (f, inst.strerror))
+        skipwarning = f == files[0]
+        pats[f] = readignorefile(f, warn, skipwarning=skipwarning)
+
     return [(f, pats[f]) for f in files if f in pats]
 
 def ignore(root, files, warn):
     '''return matcher covering patterns in 'files'.
 
     the files parsed for patterns include:
     .hgignore in the repository root
     any additional files specified in the [ui] section of ~/.hgrc
 
     trailing white space is dropped.
     the escape character is backslash.
     comments start with #.
     empty lines are skipped.
 
     lines can be of the following formats:
 
     syntax: regexp # defaults following lines to non-rooted regexps
     syntax: glob   # defaults following lines to non-rooted globs
     re:pattern     # non-rooted regular expression
     glob:pattern   # non-rooted glob
     pattern        # pattern of the current default type'''
 
     pats = readpats(root, files, warn)
 
     allpats = []
     for f, patlist in pats:
         allpats.extend(patlist)
     if not allpats:
         return util.never
 
     try:
         ignorefunc = match.match(root, '', [], allpats)
     except util.Abort:
         # Re-raise an exception where the src is the right file
         for f, patlist in pats:
             try:
                 match.match(root, '', [], patlist)
             except util.Abort, inst:
                 raise util.Abort('%s: %s' % (f, inst[0]))
 
     return ignorefunc