[PATCH] revset: use "repo.changelog" instead of "list(repo)" for resource efficiency

[FUJIWARA Katsunori]

# HG changeset patch
# User FUJIWARA Katsunori <foozy at lares.dti.ne.jp>
# Date 1361115858 -32400
# Node ID 06fb2582618f43400b38ac4c791410d2fc748d2c
# Parent  f12804d3ff801b989cb2aab1aad93047a8db46f1
revset: use "repo.changelog" instead of "list(repo)" for resource efficiency

Before this patch, some revset predicates use "list(repo)" as "subset"
to indicate "all revisions in the repo", and it immediately creates
the list object containing such revisions, even though it may not be
used: for example, "stringset" omits checking whether the revision
number corresponding to the specified string is contained in "subset"
or not, if "len(subset) == len(repo)".

This patch uses "repo.changelog" instead of "list(repo)" for resource
efficiency.

diff --git a/mercurial/revset.py b/mercurial/revset.py
--- a/mercurial/revset.py
+++ b/mercurial/revset.py
@@ -239,7 +239,7 @@
 
 def dagrange(repo, subset, x, y):
     if subset:
-        r = list(repo)
+        r = repo.changelog
         xs = _revsbetween(repo, getset(repo, r, x), getset(repo, r, y))
         s = set(subset)
         return [r for r in xs if r in s]
@@ -286,14 +286,14 @@
     """
     # i18n: "ancestor" is a keyword
     l = getlist(x)
-    rl = list(repo)
+    cl = repo.changelog
     anc = None
 
-    # (getset(repo, rl, i) for i in l) generates a list of lists
+    # (getset(repo, cl, i) for i in l) generates a list of lists
     rev = repo.changelog.rev
     ancestor = repo.changelog.ancestor
     node = repo.changelog.node
-    for revs in (getset(repo, rl, i) for i in l):
+    for revs in (getset(repo, cl, i) for i in l):
         for r in revs:
             if anc is None:
                 anc = r
@@ -305,7 +305,7 @@
     return []
 
 def _ancestors(repo, subset, x, followfirst=False):
-    args = getset(repo, list(repo), x)
+    args = getset(repo, repo.changelog, x)
     if not args:
         return []
     s = set(_revancestors(repo, args, followfirst)) | set(args)
@@ -432,7 +432,7 @@
         else:
             return [r for r in subset if matcher(repo[r].branch())]
 
-    s = getset(repo, list(repo), x)
+    s = getset(repo, repo.changelog, x)
     b = set()
     for r in s:
         b.add(repo[r].branch())
@@ -511,7 +511,7 @@
     """``children(set)``
     Child changesets of changesets in set.
     """
-    s = set(getset(repo, list(repo), x))
+    s = set(getset(repo, repo.changelog, x))
     cs = _children(repo, subset, s)
     return [r for r in subset if r in cs]
 
@@ -592,7 +592,7 @@
     return l
 
 def _descendants(repo, subset, x, followfirst=False):
-    args = getset(repo, list(repo), x)
+    args = getset(repo, repo.changelog, x)
     if not args:
         return []
     s = set(_revdescendants(repo, args, followfirst)) | set(args)
@@ -616,9 +616,9 @@
     is the same as passing all().
     """
     if x is not None:
-        args = set(getset(repo, list(repo), x))
+        args = set(getset(repo, repo.changelog, x))
     else:
-        args = set(getall(repo, list(repo), x))
+        args = set(getall(repo, repo.changelog, x))
 
     dests = set()
 
@@ -932,7 +932,7 @@
         # i18n: "limit" is a keyword
         raise error.ParseError(_("limit expects a number"))
     ss = set(subset)
-    os = getset(repo, list(repo), l[0])[:lim]
+    os = getset(repo, repo.changelog, l[0])[:lim]
     return [r for r in os if r in ss]
 
 def last(repo, subset, x):
@@ -950,14 +950,14 @@
         # i18n: "last" is a keyword
         raise error.ParseError(_("last expects a number"))
     ss = set(subset)
-    os = getset(repo, list(repo), l[0])[-lim:]
+    os = getset(repo, repo.changelog, l[0])[-lim:]
     return [r for r in os if r in ss]
 
 def maxrev(repo, subset, x):
     """``max(set)``
     Changeset with highest revision number in set.
     """
-    os = getset(repo, list(repo), x)
+    os = getset(repo, repo.changelog, x)
     if os:
         m = max(os)
         if m in subset:
@@ -994,7 +994,7 @@
     """``min(set)``
     Changeset with lowest revision number in set.
     """
-    os = getset(repo, list(repo), x)
+    os = getset(repo, repo.changelog, x)
     if os:
         m = min(os)
         if m in subset:
@@ -1044,9 +1044,9 @@
     for the first operation is selected.
     """
     if x is not None:
-        args = set(getset(repo, list(repo), x))
+        args = set(getset(repo, repo.changelog, x))
     else:
-        args = set(getall(repo, list(repo), x))
+        args = set(getall(repo, repo.changelog, x))
 
     def _firstsrc(rev):
         src = _getrevsource(repo, rev)
@@ -1096,7 +1096,7 @@
 
     ps = set()
     cl = repo.changelog
-    for r in getset(repo, list(repo), x):
+    for r in getset(repo, cl, x):
         ps.add(cl.parentrevs(r)[0])
     return [r for r in subset if r in ps]
 
@@ -1114,7 +1114,7 @@
 
     ps = set()
     cl = repo.changelog
-    for r in getset(repo, list(repo), x):
+    for r in getset(repo, cl, x):
         ps.add(cl.parentrevs(r)[1])
     return [r for r in subset if r in ps]
 
@@ -1128,7 +1128,7 @@
 
     ps = set()
     cl = repo.changelog
-    for r in getset(repo, list(repo), x):
+    for r in getset(repo, cl, x):
         ps.update(cl.parentrevs(r))
     return [r for r in subset if r in ps]