# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@fb.com>
# Date 1458239101 25200
# Node ID db19b1dc5c4590478205fd51e31a348644226075
# Parent  a91115687a7e95fa882e712b94c0cfec7aa024c1
topic: restrict 'hg prev' to current topic unless --no-topic is passed

This is far from perfect but a good start.

diff -r a91115687a7e -r db19b1dc5c45 hgext/evolve.py
--- a/hgext/evolve.py	Thu Mar 17 10:04:30 2016 -0700
+++ b/hgext/evolve.py	Thu Mar 17 11:25:01 2016 -0700
@@ -2079,6 +2079,7 @@
          [('B', 'move-bookmark', False,
              _('move active bookmark after update')),
           ('', 'merge', False, _('bring uncommitted change along')),
+          ('', 'no-topic', False, _('ignore topic and move topologically')),
           ('n', 'dry-run', False,
              _('do not perform actions, just print what would be done'))],
          '[OPTION]...')
@@ -2160,6 +2161,12 @@
             raise
 
     children = [ctx for ctx in wparents[0].children() if not ctx.obsolete()]
+    topic = getattr(repo, 'currenttopic', '')
+    filtered = []
+    if topic and not opts.get("no_topic", False):
+        filtered = [ctx for ctx in children if ctx.topic() != topic]
+        # XXX N-square membership on children
+        children = [ctx for ctx in children if ctx not in filtered]
     displayer = cmdutil.show_changeset(ui, repo, {'template': shorttemplate})
     if len(children) == 1:
         c = children[0]
@@ -2195,8 +2202,17 @@
         result = 1
     else:
         aspchildren = _aspiringchildren(repo, [repo['.'].rev()])
+        if topic:
+            filtered.extend(repo[c] for c in children
+                            if repo[c].topic() != topic)
+            # XXX N-square membership on children
+            aspchildren = [ctx for ctx in aspchildren if ctx not in filtered]
         if not opts['evolve'] or not aspchildren:
-            ui.warn(_('no children\n'))
+            if filtered:
+                ui.warn(_('no children on topic "%s"\n') % topic)
+                ui.warn(_('do you want --no-topic\n'))
+            else:
+                ui.warn(_('no children\n'))
             if aspchildren:
                 msg = _('(%i unstable changesets to be evolved here, '
                         'do you want --evolve?)\n')
diff -r a91115687a7e -r db19b1dc5c45 tests/test-evolve-topic.t
--- a/tests/test-evolve-topic.t	Thu Mar 17 10:04:30 2016 -0700
+++ b/tests/test-evolve-topic.t	Thu Mar 17 11:25:01 2016 -0700
@@ -191,3 +191,26 @@
   |
   o  0 - {} 199cc73e9a0b add aaa (draft)
   
+
+Tests next and prev behavior
+============================
+
+Basic move are restricted to the current topic
+
+  $ hg up foo
+  switching to topic foo
+  0 files updated, 0 files merged, 4 files removed, 0 files unresolved
+  $ hg prev
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  [14] add eee
+  $ hg next
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  [15] add fff
+  $ hg next
+  no children on topic "foo"
+  do you want --no-topic
+  [1]
+  $ hg next --no-topic
+  switching to topic bar
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  [16] add ggg