# HG changeset patch
# User Anton Shestakov <av6@dwimlabs.net>
# Date 1535634317 -28800
# Node ID ad4194399b47e6e13edbb45f88fd9f145d6d261c
# Parent  54eade86ac317f32dd1dd39a3523e58449efa07f
topic: handle ambiguous arguments to topic() revset

These arguments can be interpreted as either string or a revset. The decision
is made based on existence of topic with such a name. This matches the behavior
of branch() revset.

The code needs to know all topics that ever existed in the repo, because some
commands report "disappearance" of topics after certain operations, using this
revset (e.g. via stack.stack or repo.revs).

diff -r 54eade86ac31 -r ad4194399b47 CHANGELOG
--- a/CHANGELOG	Thu Aug 30 20:21:17 2018 +0800
+++ b/CHANGELOG	Thu Aug 30 21:05:17 2018 +0800
@@ -8,6 +8,11 @@
   * pick: rename the "grab" command to "pick" to avoid ambiguity with graft
   * discovery: enable obshashrange based discovery by default
 
+topic
+
+  * revset: `topic("patterns")` now handle standard patterns ("re:", etc)
+  * revset: `topic(REVS)` matches revisions with same topic as REVS
+
 8.1.2 -- 2018-08-28
 -------------------
 
diff -r 54eade86ac31 -r ad4194399b47 hgext3rd/topic/revset.py
--- a/hgext3rd/topic/revset.py	Thu Aug 30 20:21:17 2018 +0800
+++ b/hgext3rd/topic/revset.py	Thu Aug 30 21:05:17 2018 +0800
@@ -30,8 +30,6 @@
 
     If `string` starts with `re:` the remainder of the name is treated
     as a regular expression.
-
-    TODO: make `topic(revset)` work the same as `branch(revset)`.
     """
     args = revset.getargs(x, 0, 1, 'topic takes one or no arguments')
 
@@ -46,9 +44,7 @@
         # not a string, but another revset
         pass
     else:
-        if topic == '.':
-            topic = repo['.'].extra().get('topic', '')
-        _kind, _pattern, matcher = mkmatcher(topic)
+        kind, pattern, matcher = mkmatcher(topic)
 
         def matches(r):
             topic = repo[r].topic()
@@ -56,7 +52,22 @@
                 return False
             return matcher(topic)
 
-        if True:
+        if kind == 'literal':
+            # note: falls through to the revset case if no topic with this name
+            # exists and pattern kind is not specified explicitly
+
+            alltopics = set([repo.currenttopic])
+            for r in repo.unfiltered().set('all()'):
+                alltopics.add(r.topic(force=True))
+            alltopics.discard('')
+
+            if pattern in alltopics:
+                return (subset & mutable).filter(matches)
+
+            if topic.startswith('literal:'):
+                raise error.RepoLookupError("topic '%s' does not exist"
+                                            % pattern)
+        else:
             return (subset & mutable).filter(matches)
 
     s = revset.getset(repo, revset.fullreposet(repo), x)
diff -r 54eade86ac31 -r ad4194399b47 tests/test-topic.t
--- a/tests/test-topic.t	Thu Aug 30 20:21:17 2018 +0800
+++ b/tests/test-topic.t	Thu Aug 30 21:05:17 2018 +0800
@@ -741,6 +741,9 @@
   >   hg log -T '{rev}: {topic}\n' -r "$1"
   > }
 
+  $ tlog 'topic(9)'
+  9: fran
+  $ tlog 'topic(8)'
   $ tlog 'topic(head())'
   9: fran
   $ tlog 'topic(:)'
@@ -751,6 +754,15 @@
   9: fran
   $ tlog 'topic(wdir())'
   9: fran
+  $ tlog 'topic(nonsense)'
+  abort: unknown revision 'nonsense'!
+  [255]
+
+Pattern matching in topic() revset
+  $ tlog 'topic("re:nonsense")'
+  $ tlog 'topic("literal:nonsense")'
+  abort: topic 'nonsense' does not exist!
+  [255]
 
 Deactivate the topic.
   $ hg topics