revert: evaluate filesets against working directory (issue4497)

As the failing revert tests in test-fileset-generated.t show,

Revert currently creates one matcher for matching files in the working
copy and another matcher for matching files in the target
revision. The two matchers are created with different contexts, which
means filesets are evaluated differently. Then the union of the sets
of files matching the matchers in the two contexts are reverted. It
doesn't seem to make sense to use two different matchers; only the
context they're applied to should be different.

It seems very likely that the user wants the filesets to be evaluated
against the working directory, which the tests
test-fileset-generated.t also assume, so let's make it so.

I willingly admit that the largefiles code was modified by trial and
error (according to tests).

hgext/largefiles/overrides.py

@@ -765,7 +765,7 b' def overriderevert(orig, ui, repo, ctx, '
 
             def tostandin(f):
                 standin = lfutil.standin(f)
-                if standin in mctx:
+                if standin in ctx or standin in mctx:
                     return standin
                 elif standin in repo[None] or lfdirstate[f] == 'r':
                     return None
@@ -777,7 +777,7 b' def overriderevert(orig, ui, repo, ctx, '
             def matchfn(f):
                 if lfutil.isstandin(f):
                     return (origmatchfn(lfutil.splitstandin(f)) and
-                            (f in repo[None] or f in mctx))
+                            (f in ctx or f in mctx))
                 return origmatchfn(f)
             m.matchfn = matchfn
             return m

mercurial/cmdutil.py

@@ -2828,7 +2828,6 b' def revert(ui, repo, ctx, parents, *pats'
                         return
                 ui.warn("%s: %s\n" % (m.rel(path), msg))
 
-            m = scmutil.match(ctx, pats, opts)
             m.bad = badfn
             for abs in ctx.walk(m):
                 if abs not in names:

tests/test-fileset-generated.t

@@ -141,39 +141,34 b' Test log'
   
 Test revert
 
-BROKEN: the files that get undeleted were not modified, they were removed,
-and content1_content2_missing-tracked was also not modified, it was deleted
-
   $ hg revert 'set:modified()'
   reverting content1_content1_content3-tracked
   reverting content1_content2_content1-tracked
-  undeleting content1_content2_content1-untracked
-  undeleting content1_content2_content2-untracked
   reverting content1_content2_content3-tracked
-  undeleting content1_content2_content3-untracked
-  reverting content1_content2_missing-tracked
-  undeleting content1_content2_missing-untracked
   reverting missing_content2_content3-tracked
 
-BROKEN: only the files that get forgotten are correct
-
   $ hg revert 'set:added()'
   forgetting content1_missing_content1-tracked
   forgetting content1_missing_content3-tracked
-  undeleting missing_content2_content2-untracked
-  undeleting missing_content2_content3-untracked
-  reverting missing_content2_missing-tracked
-  undeleting missing_content2_missing-untracked
   forgetting missing_missing_content3-tracked
 
   $ hg revert 'set:removed()'
   undeleting content1_content1_content1-untracked
   undeleting content1_content1_content3-untracked
   undeleting content1_content1_missing-untracked
+  undeleting content1_content2_content1-untracked
+  undeleting content1_content2_content2-untracked
+  undeleting content1_content2_content3-untracked
+  undeleting content1_content2_missing-untracked
+  undeleting missing_content2_content2-untracked
+  undeleting missing_content2_content3-untracked
+  undeleting missing_content2_missing-untracked
 
   $ hg revert 'set:deleted()'
   reverting content1_content1_missing-tracked
+  reverting content1_content2_missing-tracked
   forgetting content1_missing_missing-tracked
+  reverting missing_content2_missing-tracked
   forgetting missing_missing_missing-tracked
 
   $ hg revert 'set:unknown()'