revert: add prompt before undeleting a file in -i (issue6008)

This adds a prompt that asks whether or not a removed file is to be undeleted
in `hg revert -i`.

Differential Revision: https://phab.mercurial-scm.org/D5803

mercurial/cmdutil.py

@@ -3194,9 +3194,19 b' def _performrevert(repo, parents, ctx, n'
     if node == parent and p2 == nullid:
         normal = repo.dirstate.normal
     for f in actions['undelete'][0]:
-        prntstatusmsg('undelete', f)
-        checkout(f)
-        normal(f)
+        if interactive:
+            choice = repo.ui.promptchoice(
+                _("add back removed file %s (Yn)?$$ &Yes $$ &No") % f)
+            if choice == 0:
+                prntstatusmsg('undelete', f)
+                checkout(f)
+                normal(f)
+            else:
+                excluded_files.append(f)
+        else:
+            prntstatusmsg('undelete', f)
+            checkout(f)
+            normal(f)
 
     copied = copies.pathcopies(repo[parent], ctx)
 

tests/test-revert-interactive.t

@@ -424,3 +424,24 b' When specified pattern does not exist, w'
   b: no such file in rev b40d1912accf
 
   $ cd ..
+
+Prompt before undeleting file(issue6008)
+  $ hg init repo
+  $ cd repo
+  $ echo a > a
+  $ hg ci -qAm a
+  $ hg rm a
+  $ hg revert -i<<EOF
+  > y
+  > EOF
+  add back removed file a (Yn)? y
+  undeleting a
+  $ ls
+  a
+  $ hg rm a
+  $ hg revert -i<<EOF
+  > n
+  > EOF
+  add back removed file a (Yn)? n
+  $ ls
+  $ cd ..