[PATCH 2 of 2 V2] convert: add config option for disabling ancestor parent checks

Durham Goode durham at fb.com
Mon Jul 6 19:25:35 CDT 2015


# HG changeset patch
# User Durham Goode <durham at fb.com>
# Date 1435610664 25200
#      Mon Jun 29 13:44:24 2015 -0700
# Node ID 0dfd9b064e56280fc7f3345382714dc28d913362
# Parent  82d6924ece5c04c4be8b7931da5697961cca346f
convert: add config option for disabling ancestor parent checks

When converting merge commits, convert checks if any of the parents are
ancestors of any of the other parents. To do this, it builds an ancestor list
for every commit in the repository. On large repos this can take a long time
(30min+). Let's add an option for disabling this check to preserve performance.

The downside of this is that it may create unnecessary parent connections when
enabled (which is unfortunate, but not incorrect).

To verify, I ran the convert tests with the flag enabled, and verified the graph
changes were all just to add new parents that were ancestors of existing
parents.

diff --git a/hgext/convert/filemap.py b/hgext/convert/filemap.py
--- a/hgext/convert/filemap.py
+++ b/hgext/convert/filemap.py
@@ -156,6 +156,9 @@ class filemap_source(converter_source):
         self.origparents = {}
         self.children = {}
         self.seenchildren = {}
+        # experimental config: convert.ignoreancestorcheck
+        self.ignoreancestorcheck = self.ui.configbool('convert',
+                                                      'ignoreancestorcheck')
 
     def before(self):
         self.base.before()
@@ -306,7 +309,7 @@ class filemap_source(converter_source):
 
     def getchanges(self, rev, full):
         parents = self.commits[rev].parents
-        if len(parents) > 1:
+        if len(parents) > 1 and not self.ignoreancestorcheck:
             self.rebuild()
 
         # To decide whether we're interested in rev we:
@@ -332,9 +335,11 @@ class filemap_source(converter_source):
             mp1 = self.parentmap[p1]
             if mp1 == SKIPREV or mp1 in knownparents:
                 continue
-            isancestor = any(p2 for p2 in parents
-                                  if p1 != p2 and mp1 != self.parentmap[p2]
-                                  and mp1 in self.wantedancestors[p2])
+
+            isancestor = (not self.ignoreancestorcheck and
+                          any(p2 for p2 in parents
+                              if p1 != p2 and mp1 != self.parentmap[p2]
+                                 and mp1 in self.wantedancestors[p2]))
             if not isancestor and not hasbranchparent and len(parents) > 1:
                 # This could be expensive, avoid unnecessary calls.
                 if self._cachedcommit(p1).branch == branch:


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