copies: use dedicated `_revinfo_getter` function and call

We want to return data in a different form, so we need different revinfo
function. At that point it make sense to have different getter.

Differential Revision: https://phab.mercurial-scm.org/D9115

mercurial/copies.py

@@ -201,7 +201,6 def _revinfo_getter(repo):
 
         return ismerged
 
-    if repo.filecopiesmode == b'changeset-sidedata':
         changelogrevision = cl.changelogrevision
         flags = cl.flags
 
@@ -260,15 +259,6 def _revinfo_getter(repo):
                 value = (p1, p2, p1copies, p2copies, removed, get_ismerged(rev))
             return value
 
-    else:
-
-        def revinfo(rev):
-            p1, p2 = parents(rev)
-            ctx = repo[rev]
-            p1copies, p2copies = ctx._copies
-            removed = ctx.filesremoved()
-            return p1, p2, p1copies, p2copies, removed, get_ismerged(rev)
-
     return revinfo
 
 
@@ -278,7 +268,6 def _changesetforwardcopies(a, b, match)
 
     repo = a.repo().unfiltered()
     children = {}
-    revinfo = _revinfo_getter(repo)
 
     cl = repo.changelog
     isancestor = cl.isancestorrev  # XXX we should had chaching to this.
@@ -311,10 +300,12 def _changesetforwardcopies(a, b, match)
     revs = sorted(iterrevs)
 
     if repo.filecopiesmode == b'changeset-sidedata':
+        revinfo = _revinfo_getter(repo)
         return _combine_changeset_copies(
             revs, children, b.rev(), revinfo, match, isancestor
         )
     else:
+        revinfo = _revinfo_getter_extra(repo)
         return _combine_changeset_copies_extra(
             revs, children, b.rev(), revinfo, match, isancestor
         )
@@ -428,6 +419,45 def _merge_copies_dict(minor, major, isa
                 minor[dest] = value
 
 
+def _revinfo_getter_extra(repo):
+    """return a function that return multiple data given a <rev>"i
+
+    * p1: revision number of first parent
+    * p2: revision number of first parent
+    * p1copies: mapping of copies from p1
+    * p2copies: mapping of copies from p2
+    * removed: a list of removed files
+    * ismerged: a callback to know if file was merged in that revision
+    """
+    cl = repo.changelog
+    parents = cl.parentrevs
+
+    def get_ismerged(rev):
+        ctx = repo[rev]
+
+        def ismerged(path):
+            if path not in ctx.files():
+                return False
+            fctx = ctx[path]
+            parents = fctx._filelog.parents(fctx._filenode)
+            nb_parents = 0
+            for n in parents:
+                if n != node.nullid:
+                    nb_parents += 1
+            return nb_parents >= 2
+
+        return ismerged
+
+    def revinfo(rev):
+        p1, p2 = parents(rev)
+        ctx = repo[rev]
+        p1copies, p2copies = ctx._copies
+        removed = ctx.filesremoved()
+        return p1, p2, p1copies, p2copies, removed, get_ismerged(rev)
+
+    return revinfo
+
+
 def _combine_changeset_copies_extra(
     revs, children, targetrev, revinfo, match, isancestor
 ):