import: handle git renames and --similarity (issue3187)

There is no reason to discard copy sources from the set of files considered by
addremove(). It was done to handle the case where a first patch would create
'a' and a second one would move 'a' to 'b'. If these patches were applied with
--no-commit, 'a' would first be marked as added, then unlinked and dropped from
the dirstate but still passed to addremove(). A better fix is thus to exclude
removed files which ends being dropped from the dirstate instead of removed.

Reported by Jason Harris <[e-mail]>

mercurial/patch.py

@@ -475,9 +475,15 b' class workingbackend(fsbackend):'
         addremoved = set(self.changed)
         for src, dst in self.copied:
             scmutil.dirstatecopy(self.ui, self.repo, wctx, src, dst)
-            addremoved.discard(src)
-        if (not self.similarity) and self.removed:
+        if self.removed:
             wctx.forget(sorted(self.removed))
+            for f in self.removed:
+                if f not in self.repo.dirstate:
+                    # File was deleted and no longer belongs to the
+                    # dirstate, it was probably marked added then
+                    # deleted, and should not be considered by
+                    # addremove().
+                    addremoved.discard(f)
         if addremoved:
             cwd = self.repo.getcwd()
             if cwd:

tests/test-import-git.t

@@ -402,6 +402,23 b' Renames and strip'
   A b
     a
   R a
+
+Renames, similarity and git diff
+
+  $ hg revert -aC
+  undeleting a
+  forgetting b
+  $ rm b
+  $ hg import --similarity 90 --no-commit - <<EOF
+  > diff --git a/a b/b
+  > rename from a
+  > rename to b
+  > EOF
+  applying patch from stdin
+  $ hg st --copies
+  A b
+    a
+  R a
   $ cd ..
 
 Pure copy with existing destination

tests/test-import.t

@@ -663,7 +663,6 b' test import with similarity and git and '
   applying ../rename.diff
   patching file a
   patching file b
-  removing a
   adding b
   recording removal of a as rename to b (88% similar)
   applied to working directory
@@ -679,7 +678,6 b' test import with similarity and git and '
   applying ../rename.diff
   patching file a
   patching file b
-  removing a
   adding b
   applied to working directory
   $ hg st -C