diff mercurial/exchangev2.py @ 45788:a5206e71c536

revlog: extend addgroup() with callback for duplicates

The addgroup() interface currently doesn't allow the caller to keep
track of duplicated nodes except by looking at the returned node list.
Add an optional second callback for this purpose and change the return
type to a boolean. This allows follow-up changes to use more efficient
storage for the node list in places that are memory-sensitive.

Differential Revision: https://phab.mercurial-scm.org/D9231

--- a/mercurial/exchangev2.py	Wed Oct 07 14:26:47 2020 +0530
+++ b/mercurial/exchangev2.py	Sun Oct 18 22:18:02 2020 +0200
@@ -343,16 +343,21 @@
     )
 
     manifestnodes = {}
+    added = []
 
     def linkrev(node):
         repo.ui.debug(b'add changeset %s\n' % short(node))
         # Linkrev for changelog is always self.
         return len(cl)
 
+    def ondupchangeset(cl, node):
+        added.append(node)
+
     def onchangeset(cl, node):
         progress.increment()
 
         revision = cl.changelogrevision(node)
+        added.append(node)
 
         # We need to preserve the mapping of changelog revision to node
         # so we can set the linkrev accordingly when manifests are added.
@@ -403,8 +408,12 @@
                 0,
             )
 
-    added = cl.addgroup(
-        iterrevisions(), linkrev, weakref.proxy(tr), addrevisioncb=onchangeset
+    cl.addgroup(
+        iterrevisions(),
+        linkrev,
+        weakref.proxy(tr),
+        addrevisioncb=onchangeset,
+        duplicaterevisioncb=ondupchangeset,
     )
 
     progress.complete()
@@ -516,12 +525,15 @@
             # Chomp off header object.
             next(objs)
 
-            added.extend(
-                rootmanifest.addgroup(
-                    iterrevisions(objs, progress),
-                    linkrevs.__getitem__,
-                    weakref.proxy(tr),
-                )
+            def onchangeset(cl, node):
+                added.append(node)
+
+            rootmanifest.addgroup(
+                iterrevisions(objs, progress),
+                linkrevs.__getitem__,
+                weakref.proxy(tr),
+                addrevisioncb=onchangeset,
+                duplicaterevisioncb=onchangeset,
             )
 
     progress.complete()