--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mercurial/templatekw.py	Sun Dec 13 18:06:23 2009 +0100
@@ -0,0 +1,69 @@
+# templatekw.py - common changeset template keywords
+#
+# Copyright 2005-2009 Matt Mackall <mpm@selenic.com>
+#
+# This software may be used and distributed according to the terms of the
+# GNU General Public License version 2, incorporated herein by reference.
+
+
+def showlist(templ, name, values, plural=None, **args):
+    '''expand set of values.
+    name is name of key in template map.
+    values is list of strings or dicts.
+    plural is plural of name, if not simply name + 's'.
+
+    expansion works like this, given name 'foo'.
+
+    if values is empty, expand 'no_foos'.
+
+    if 'foo' not in template map, return values as a string,
+    joined by space.
+
+    expand 'start_foos'.
+
+    for each value, expand 'foo'. if 'last_foo' in template
+    map, expand it instead of 'foo' for last key.
+
+    expand 'end_foos'.
+    '''
+    if plural: names = plural
+    else: names = name + 's'
+    if not values:
+        noname = 'no_' + names
+        if noname in templ:
+            yield templ(noname, **args)
+        return
+    if name not in templ:
+        if isinstance(values[0], str):
+            yield ' '.join(values)
+        else:
+            for v in values:
+                yield dict(v, **args)
+        return
+    startname = 'start_' + names
+    if startname in templ:
+        yield templ(startname, **args)
+    vargs = args.copy()
+    def one(v, tag=name):
+        try:
+            vargs.update(v)
+        except (AttributeError, ValueError):
+            try:
+                for a, b in v:
+                    vargs[a] = b
+            except ValueError:
+                vargs[name] = v
+        return templ(tag, **vargs)
+    lastname = 'last_' + name
+    if lastname in templ:
+        last = values.pop()
+    else:
+        last = None
+    for v in values:
+        yield one(v)
+    if last is not None:
+        yield one(last, tag=lastname)
+    endname = 'end_' + names
+    if endname in templ:
+        yield templ(endname, **args)
+