[PATCH 4 of 5 RESEND] grep: use "found" instead of "filerevmatches" examination for efficiency

[FUJIWARA Katsunori]

# HG changeset patch
# User FUJIWARA Katsunori <foozy at lares.dti.ne.jp>
# Date 1392461645 -32400
#      Sat Feb 15 19:54:05 2014 +0900
# Node ID 07301d80e333276ad9b1c5da007e0084e745749e
# Parent  34798e580fada8795f71cee5ccb755c4f55e7e7a
grep: use "found" instead of "filerevmatches" examination for efficiency

Before this patch, internal function "display()" of "hg grep" stores
whether matching is already found or not into the dictionary
"filerevmatches" by "(fn, rev)" tuple as the key.

But this is redundant, because:

  - "filerevmatches" is local variable of "display()", so each
    "display()" invocations don't affect others

  - both "fn" and "rev" (gotten from "ctx" argument) are never changed
    in each "display()" invocations

Then, "filerevmatches" should have only one entry at most, and "(fn,
rev) in filerevmatches" should be equal to "found".

This patch uses "found" instead of "filerevmatches" examination for
efficiency.

diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -3239,7 +3239,6 @@
         rev = ctx.rev()
         datefunc = ui.quiet and util.shortdate or util.datestr
         found = False
-        filerevmatches = {}
         @util.cachefunc
         def binary():
             flog = getfile(fn)
@@ -3262,10 +3261,8 @@
             if opts.get('date'):
                 cols.append((datefunc(ctx.date()), 'grep.date'))
             if opts.get('files_with_matches'):
-                c = (fn, rev)
-                if c in filerevmatches:
+                if found:
                     continue
-                filerevmatches[c] = 1
             else:
                 before = l.line[:l.colstart]
                 match = l.line[l.colstart:l.colend]