[PATCH 2 of 7] tags: do not feed dictionaries to 'findglobaltags'

[Pierre-Yves David]

# HG changeset patch
# User Pierre-Yves David <pierre-yves.david at ens-lyon.org>
# Date 1490674429 -7200
#      Tue Mar 28 06:13:49 2017 +0200
# Node ID 147b98bfa4afbaf608d9e1f5227a48a46e386ea4
# Parent  1e77e505e7bacf59d1200714dc92e827523d7301
# EXP-Topic tags
# Available At https://www.mercurial-scm.org/repo/users/marmoute/mercurial/
#              hg pull https://www.mercurial-scm.org/repo/users/marmoute/mercurial/ -r 147b98bfa4af
tags: do not feed dictionaries to 'findglobaltags'

The code assert that these dictionnary are empty anyway. So we can as well be
more explicit and have the function returns the dictionaries directly.

diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -707,10 +707,11 @@ class localrepository(object):
         # be one tagtype for all such "virtual" tags?  Or is the status
         # quo fine?
 
-        alltags = {}                    # map tag name to (node, hist)
-        tagtypes = {}
 
-        tagsmod.findglobaltags(self.ui, self, alltags, tagtypes)
+        globaldata = tagsmod.findglobaltags(self.ui, self)
+        alltags = globaldata[0]   # map tag name to (node, hist)
+        tagtypes = globaldata[1]  # map tag name to tag type
+
         tagsmod.readlocaltags(self.ui, self, alltags, tagtypes)
 
         # Build the return dicts.  Have to re-encode tag names because
diff --git a/mercurial/tags.py b/mercurial/tags.py
--- a/mercurial/tags.py
+++ b/mercurial/tags.py
@@ -78,23 +78,18 @@ from . import (
 # The most recent changeset (in terms of revlog ordering for the head
 # setting it) for each tag is last.
 
-def findglobaltags(ui, repo, alltags, tagtypes):
-    '''Find global tags in a repo.
+def findglobaltags(ui, repo):
+    '''Find global tags in a repo: return (alltags, tagtypes)
 
     "alltags" maps tag name to (node, hist) 2-tuples.
 
     "tagtypes" maps tag name to tag type. Global tags always have the
     "global" tag type.
 
-    The "alltags" and "tagtypes" dicts are updated in place. Empty dicts
-    should be passed in.
-
     The tags cache is read and updated as a side-effect of calling.
     '''
-    # This is so we can be lazy and assume alltags contains only global
-    # tags when we pass it to _writetagcache().
-    assert len(alltags) == len(tagtypes) == 0, \
-           "findglobaltags() should be called first"
+    alltags = {}
+    tagtypes = {}
 
     (heads, tagfnode, valid, cachetags, shouldwrite) = _readtagcache(ui, repo)
     if cachetags is not None:
@@ -103,7 +98,7 @@ def findglobaltags(ui, repo, alltags, ta
         # cases where a global tag should outrank a local tag but won't,
         # because cachetags does not contain rank info?
         _updatetags(cachetags, 'global', alltags, tagtypes)
-        return
+        return alltags, tagtypes
 
     seen = set()  # set of fnode
     fctx = None
@@ -125,6 +120,7 @@ def findglobaltags(ui, repo, alltags, ta
     # and update the cache (if necessary)
     if shouldwrite:
         _writetagcache(ui, repo, valid, alltags)
+    return alltags, tagtypes
 
 def readlocaltags(ui, repo, alltags, tagtypes):
     '''Read local tags in repo. Update alltags and tagtypes.'''