revert: makes interactive mode ask to forget added files (issue4936)

Before this patch revert interactive mode unconditionally forgets
added files. This patch fixes this by asking user if he wants
to forget added file. If user doesn't want to forget given file,
it is added to matcher_opts exclude list, to not reviewing it
later with other modified files.

mercurial/cmdutil.py

@@ -3130,12 +3130,25 b' def _performrevert(repo, parents, ctx, a'
     """
     parent, p2 = parents
     node = ctx.node()
+    excluded_files = []
+    matcher_opts = {"exclude": excluded_files}
+
     def checkout(f):
         fc = ctx[f]
         repo.wwrite(f, fc.data(), fc.flags())
 
     audit_path = pathutil.pathauditor(repo.root)
     for f in actions['forget'][0]:
+        if interactive:
+            choice = \
+                repo.ui.promptchoice(
+                    _("forget added file %s (yn)?$$ &Yes $$ &No")
+                    % f)
+            if choice == 0:
+                repo.dirstate.drop(f)
+            else:
+                excluded_files.append(repo.wjoin(f))
+        else:
         repo.dirstate.drop(f)
     for f in actions['remove'][0]:
         audit_path(f)
@@ -3162,7 +3175,7 b' def _performrevert(repo, parents, ctx, a'
     if interactive:
         # Prompt the user for changes to revert
         torevert = [repo.wjoin(f) for f in actions['revert'][0]]
-        m = scmutil.match(ctx, torevert, {})
+        m = scmutil.match(ctx, torevert, matcher_opts)
         diffopts = patch.difffeatureopts(repo.ui, whitespace=True)
         diffopts.nodates = True
         diffopts.git = True

tests/test-revert-interactive.t

@@ -15,6 +15,7 b' 10 run the same test than 8 from within '
   > interactive = true
   > [extensions]
   > record =
+  > purge = 
   > EOF
 
 
@@ -377,3 +378,26 b' Check the experimental config to invert '
    5
    d
   +lastline
+
+  $ hg update -C .
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ hg purge
+  $ touch newfile
+  $ hg add newfile
+  $ hg status
+  A newfile
+  $ hg revert -i <<EOF
+  > n
+  > EOF
+  forgetting newfile
+  forget added file newfile (yn)? n
+  $ hg status
+  A newfile
+  $ hg revert -i <<EOF
+  > y
+  > EOF
+  forgetting newfile
+  forget added file newfile (yn)? y
+  $ hg status
+  ? newfile
+