phases: use revision number in new_heads
authorPierre-Yves David <pierre-yves.david@octobus.net>
Fri, 05 Apr 2024 11:33:47 +0200
changeset 51605 b70628a9aa7e
parent 51604 87655e6dc108
child 51606 e0194b3ea312
phases: use revision number in new_heads All graph operations will be done using revision numbers, so passing nodes only means they will eventually get converted to revision numbers internally. As part of an effort to align the code on using revision number we make the `phases.newheads` function operated on revision number, taking them as input and using them in returns, instead of the node-id it used to consume and produce. This is part of multiple changesets effort to translate more part of the logic, but is done step by step to facilitate the identification of issue that might arise in mercurial core and extensions. To make the change simpler to handle for third party extensions, we also rename the function, using a more modern form. This will help detecting the different between the node-id version and the rev-num version. I also take this as an opportunity to add some comment about possible performance improvement for the future. They don't matter too much now, but they are worse exploring in a while.
mercurial/discovery.py
mercurial/phases.py
--- a/mercurial/discovery.py	Mon Apr 08 15:11:49 2024 +0200
+++ b/mercurial/discovery.py	Fri Apr 05 11:33:47 2024 +0200
@@ -190,7 +190,12 @@
         if len(missing) == len(allmissing):
             ancestorsof = onlyheads
         else:  # update missing heads
-            ancestorsof = phases.newheads(repo, onlyheads, excluded)
+            to_rev = repo.changelog.index.rev
+            to_node = repo.changelog.node
+            excluded_revs = [to_rev(r) for r in excluded]
+            onlyheads_revs = [to_rev(r) for r in onlyheads]
+            new_heads = phases.new_heads(repo, onlyheads_revs, excluded_revs)
+            ancestorsof = [to_node(r) for r in new_heads]
         og.ancestorsof = ancestorsof
     if portable:
         # recompute common and ancestorsof as if -r<rev> had been given for
--- a/mercurial/phases.py	Mon Apr 08 15:11:49 2024 +0200
+++ b/mercurial/phases.py	Fri Apr 05 11:33:47 2024 +0200
@@ -109,6 +109,7 @@
 from typing import (
     Any,
     Callable,
+    Collection,
     Dict,
     Iterable,
     List,
@@ -127,7 +128,6 @@
 )
 from . import (
     error,
-    pycompat,
     requirements,
     smartset,
     txnutil,
@@ -1125,9 +1125,11 @@
             msg = _(b'ignoring unexpected root from remote: %i %s\n')
             repo.ui.warn(msg % (phase, nhex))
     # compute heads
+    subset_revs = [to_rev(n) for n in subset]
+    public_heads = new_heads(repo, subset_revs, draft_roots)
     draft_nodes = [to_node(r) for r in draft_roots]
-    publicheads = newheads(repo, subset, draft_nodes)
-    return publicheads, draft_nodes
+    public_nodes = [to_node(r) for r in public_heads]
+    return public_nodes, draft_nodes
 
 
 class remotephasessummary:
@@ -1152,7 +1154,11 @@
         self.draftheads = [c.node() for c in dheads]
 
 
-def newheads(repo, heads, roots):
+def new_heads(
+    repo,
+    heads: Collection[int],
+    roots: Collection[int],
+) -> Collection[int]:
     """compute new head of a subset minus another
 
     * `heads`: define the first subset
@@ -1161,16 +1167,15 @@
     # phases > dagop > patch > copies > scmutil > obsolete > obsutil > phases
     from . import dagop
 
-    repo = repo.unfiltered()
-    cl = repo.changelog
-    rev = cl.index.get_rev
     if not roots:
         return heads
-    if not heads or heads == [repo.nullid]:
+    if not heads or heads == [nullrev]:
         return []
     # The logic operated on revisions, convert arguments early for convenience
-    new_heads = {rev(n) for n in heads if n != repo.nullid}
-    roots = [rev(n) for n in roots]
+    # PERF-XXX: maybe heads could directly comes as a set without impacting
+    # other user of that value
+    new_heads = set(heads)
+    new_heads.discard(nullrev)
     # compute the area we need to remove
     affected_zone = repo.revs(b"(%ld::%ld)", roots, new_heads)
     # heads in the area are no longer heads
@@ -1188,7 +1193,9 @@
         pruned = dagop.reachableroots(repo, candidates, prunestart)
         new_heads.difference_update(pruned)
 
-    return pycompat.maplist(cl.node, sorted(new_heads))
+    # PERF-XXX: do we actually need a sorted list here? Could we simply return
+    # a set?
+    return sorted(new_heads)
 
 
 def newcommitphase(ui: "uimod.ui") -> int: