# HG changeset patch
# User Jun Wu <quark@fb.com>
# Date 2017-05-04 05:20:44
# Node ID 776127b29a5cb8134315b726a6f06badde80db46
# Parent  e62cf13e085898484d956769a6e2d48621ed2def

diff: use fctx.size() to test empty

fctx.size() could have a fast path that does not require loading content.

diff --git a/mercurial/patch.py b/mercurial/patch.py
--- a/mercurial/patch.py
+++ b/mercurial/patch.py
@@ -2508,6 +2508,9 @@ def trydiff(repo, revs, ctx1, ctx2, modi
         revinfo = ' '.join(["-r %s" % rev for rev in revs])
         return 'diff %s %s' % (revinfo, f)
 
+    def isempty(fctx):
+        return fctx is None or fctx.size() == 0
+
     date1 = util.datestr(ctx1.date())
     date2 = util.datestr(ctx2.date())
 
@@ -2546,9 +2549,9 @@ def trydiff(repo, revs, ctx1, ctx2, modi
                 # copy/rename
                 f2 in copy or
                 # empty file creation
-                (not f1 and not content2) or
+                (not f1 and isempty(fctx2)) or
                 # empty file deletion
-                (not content1 and not f2) or
+                (isempty(fctx1) and not f2) or
                 # create with flags
                 (not f1 and flag2) or
                 # change flags