Always copy the necessary files before applying a git patch

This patch removes the "copymod" attribute from the gitpatch
class.

AFAICS, that attribute was only used to delay the copying of
renamed/copied files if there are no other changes to the target,
but in this case, if there are changes to the source, we'll end
up copying the wrong version.

This should fix issue762.

mercurial/patch.py

@@ -151,7 +151,6 b' def readgitpatch(fp, firstline=None):'
             self.oldpath = None
             self.mode = None
             self.op = 'MODIFY'
-            self.copymod = False
             self.lineno = 0
             self.binary = False
 
@@ -182,7 +181,6 b' def readgitpatch(fp, firstline=None):'
         elif gp:
             if line.startswith('--- '):
                 if gp.op in ('COPY', 'RENAME'):
-                    gp.copymod = True
                     dopatch |= GP_FILTER
                 gitpatches.append(gp)
                 gp = None
@@ -858,7 +856,7 b' def applydiff(ui, fp, changed, strip=1, '
 
         (dopatch, gitpatches) = readgitpatch(fp, firstline)
         for gp in gitpatches:
-            if gp.copymod:
+            if gp.op in ('COPY', 'RENAME'):
                 copyfile(gp.oldpath, gp.path, basedir=cwd)
 
         fp.seek(pos)
@@ -1030,15 +1028,13 b' def updatedir(ui, repo, patches):'
     for f in patches:
         ctype, gp = patches[f]
         if ctype == 'RENAME':
-            copies.append((gp.oldpath, gp.path, gp.copymod))
+            copies.append((gp.oldpath, gp.path))
             removes[gp.oldpath] = 1
         elif ctype == 'COPY':
-            copies.append((gp.oldpath, gp.path, gp.copymod))
+            copies.append((gp.oldpath, gp.path))
         elif ctype == 'DELETE':
             removes[gp.path] = 1
-    for src, dst, after in copies:
-        if not after:
-            copyfile(src, dst, repo.root)
+    for src, dst in copies:
         repo.copy(src, dst)
     removes = removes.keys()
     if removes:

tests/test-git-import

@@ -198,3 +198,19 b' index 0000000..257cc56'
 EOF
 cat "foo bar"
 
+echo % copy then modify the original file
+hg import -m copy-mod-orig - <<EOF
+diff --git a/foo2 b/foo2
+index 257cc56..fe08ec6 100644
+--- a/foo2
++++ b/foo2
+@@ -1 +1,2 @@
+ foo
++new line
+diff --git a/foo2 b/foo3
+similarity index 100%
+copy from foo2
+copy to foo3
+EOF
+
+cat foo3

tests/test-git-import.out

@@ -63,3 +63,6 b' a874b471193996e7cb034bb301cac7bdaf3e3f46'
 % filenames with spaces
 applying patch from stdin
 foo
+% copy then modify the original file
+applying patch from stdin
+foo