commit: return 1 for interactive commit with no changes (issue5397)

For consistency with non interactive commit

mercurial/commands.py

@@ -1638,9 +1638,11 b' def commit(ui, repo, *pats, **opts):'
 def _docommit(ui, repo, *pats, **opts):
     if opts.get('interactive'):
         opts.pop('interactive')
-        cmdutil.dorecord(ui, repo, commit, None, False,
-                        cmdutil.recordfilter, *pats, **opts)
-        return
+        ret = cmdutil.dorecord(ui, repo, commit, None, False,
+                               cmdutil.recordfilter, *pats, **opts)
+        # ret can be 0 (no changes to record) or the value returned by
+        # commit(), 1 if nothing changed or None on success.
+        return 1 if ret == 0 else ret
 
     if opts.get('subrepos'):
         if opts.get('amend'):

tests/test-commit-interactive-curses.t

@@ -37,6 +37,7 b' Committing some changes but stopping on '
   > EOF
   $ hg commit -i  -m "a" -d "0 0"
   no changes to record
+  [1]
   $ hg tip
   changeset:   -1:000000000000
   tag:         tip
@@ -60,6 +61,7 b' Committing some changes'
 Check that commit -i works with no changes
   $ hg commit -i
   no changes to record
+  [1]
 
 Committing only one file
 

tests/test-commit-interactive.t

@@ -29,6 +29,7 b' Select no files'
   examine changes to 'empty-rw'? [Ynesfdaq?] n
   
   no changes to record
+  [1]
 
   $ hg tip -p
   changeset:   -1:000000000000
@@ -1376,6 +1377,7 b' Removing changes from patch'
   record this change to 'editedfile'? [Ynesfdaq?] e
   
   no changes to record
+  [1]
   $ cat editedfile
   This change will not be committed
   This is the second line
@@ -1487,6 +1489,7 b' session'
   record this change to 'editedfile'? [Ynesfdaq?] n
   
   no changes to record
+  [1]
 
 
 random text in random positions is still an error