# HG changeset patch
# User Martin von Zweigbergk <martinvonz@google.com>
# Date 1556911920 25200
# Node ID 6770df6e4365a8b1ffaa011e6a5441b398a32c55
# Parent  32338e27bb9d437892aa32fcb13b427fa5ab56ee
tags: avoid double-reversing a list

Differential Revision: https://phab.mercurial-scm.org/D6337

diff -r 32338e27bb9d -r 6770df6e4365 mercurial/tags.py
--- a/mercurial/tags.py	Mon Mar 11 02:35:18 2019 +0100
+++ b/mercurial/tags.py	Fri May 03 12:32:00 2019 -0700
@@ -90,7 +90,7 @@
     unfi = repo.unfiltered()
     tonode = unfi.changelog.node
     nodes = [tonode(r) for r in revs]
-    fnodes = _getfnodes(ui, repo, nodes[::-1]) # reversed help the cache
+    fnodes = _getfnodes(ui, repo, nodes)
     fnodes = _filterfnodes(fnodes, nodes)
     return fnodes
 
@@ -458,7 +458,8 @@
     # This is the most expensive part of finding tags, so performance
     # depends primarily on the size of newheads.  Worst case: no cache
     # file, so newheads == repoheads.
-    cachefnode = _getfnodes(ui, repo, repoheads)
+    # Reversed order helps the cache ('repoheads' is in descending order)
+    cachefnode = _getfnodes(ui, repo, reversed(repoheads))
 
     # Caller has to iterate over all heads, but can use the filenodes in
     # cachefnode to get to each .hgtags revision quickly.
@@ -473,7 +474,7 @@
     starttime = util.timer()
     fnodescache = hgtagsfnodescache(repo.unfiltered())
     cachefnode = {}
-    for node in reversed(nodes):
+    for node in nodes:
         fnode = fnodescache.getfnode(node)
         if fnode != nullid:
             cachefnode[node] = fnode