match: support reading pattern lists from files

mercurial/help/patterns.txt

@@ -20,6 +20,11 @@ across path separators and ``{a,b}`` to mean "a or b".
 To use a Perl/Python regular expression, start a name with ``re:``.
 Regexp pattern matching is anchored at the root of the repository.
 
+To read name patterns from a file, use ``listfile:`` or ``listfile0:``.
+The latter expects null delimited patterns while the former expects line
+feeds. Each string read from the file is itself treated as a file
+pattern.
+
 Plain examples::
 
   path:foo/bar   a name bar in a directory named foo in the root
@@ -39,3 +44,8 @@ Glob examples::
 Regexp examples::
 
   re:.*\.c$      any name ending in ".c", anywhere in the repository
+
+File examples::
+
+  listfile:list.txt  read list from list.txt with one file pattern per line
+  listfile0:list.txt read list from list.txt with null byte delimiters

mercurial/match.py

@@ -161,7 +161,8 @@ def _patsplit(pat, default):
     actual pattern."""
     if ':' in pat:
         kind, val = pat.split(':', 1)
-        if kind in ('re', 'glob', 'path', 'relglob', 'relpath', 'relre'):
+        if kind in ('re', 'glob', 'path', 'relglob', 'relpath', 'relre',
+                    'listfile', 'listfile0'):
             return kind, val
     return default, pat
 
@@ -270,6 +271,15 @@ def _normalize(names, default, root, cwd, auditor):
             name = util.canonpath(root, cwd, name, auditor)
         elif kind in ('relglob', 'path'):
             name = util.normpath(name)
+        elif kind in ('listfile', 'listfile0'):
+            delimiter = kind == 'listfile0' and '\0' or '\n'
+            try:
+                files = open(name, 'r').read().split(delimiter)
+                files = [f for f in files if f]
+            except EnvironmentError:
+                raise util.Abort(_("unable to read file list (%s)") % name)
+            pats += _normalize(files, default, root, cwd, auditor)
+            continue
 
         pats.append((kind, name))
     return pats