Patchwork [2,of,2] subrepo: add basic support to hgsubrepo for the files command

diff --git a/mercurial/cmdutil.py b/mercurial/cmdutil.py
--- a/mercurial/cmdutil.py
+++ b/mercurial/cmdutil.py
@@ -2261,7 +2261,7 @@ 
     forgot.extend(f for f in forget if f not in rejected)
     return bad, forgot
 
-def files(ui, ctx, m, fm, fmt):
+def files(ui, ctx, m, fm, fmt, subrepos):
     rev = ctx.rev()
     ret = 1
     ds = ctx.repo().dirstate
@@ -2277,6 +2277,17 @@ 
         fm.write('path', fmt, m.rel(f))
         ret = 0
 
+    if subrepos:
+        for subpath in sorted(ctx.substate):
+            sub = ctx.sub(subpath)
+            try:
+                submatch = matchmod.narrowmatcher(subpath, m)
+                if sub.printfiles(ui, submatch, fm, fmt) == 0:
+                    ret = 0
+            except error.LookupError:
+                ui.status(_("skipping missing subrepository: %s\n")
+                               % m.abs(subpath))
+
     return ret
 
 def remove(ui, repo, m, prefix, after, force, subrepos):
diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -3225,7 +3225,7 @@ 
 @command('files',
     [('r', 'rev', '', _('search the repository as it is in REV'), _('REV')),
      ('0', 'print0', None, _('end filenames with NUL, for use with xargs')),
-    ] + walkopts + formatteropts,
+    ] + walkopts + formatteropts + subrepoopts,
     _('[OPTION]... [PATTERN]...'))
 def files(ui, repo, *pats, **opts):
     """list tracked files
@@ -3280,7 +3280,7 @@ 
     fmt = '%s' + end
 
     m = scmutil.match(ctx, pats, opts)
-    ret = cmdutil.files(ui, ctx, m, fm, fmt)
+    ret = cmdutil.files(ui, ctx, m, fm, fmt, opts.get('subrepos'))
 
     fm.end()
 
diff --git a/mercurial/help/subrepos.txt b/mercurial/help/subrepos.txt
--- a/mercurial/help/subrepos.txt
+++ b/mercurial/help/subrepos.txt
@@ -109,6 +109,10 @@ 
     elements. Git subrepositories do not support --include/--exclude.
     Subversion subrepositories are currently silently ignored.
 
+:files: files does not recurse into subrepos unless -S/--subrepos is
+    specified.  Git and Subversion subrepositories are currently
+    silently ignored.
+
 :forget: forget currently only handles exact file matches in subrepos.
     Git and Subversion subrepositories are currently silently ignored.
 
diff --git a/mercurial/subrepo.py b/mercurial/subrepo.py
--- a/mercurial/subrepo.py
+++ b/mercurial/subrepo.py
@@ -469,6 +469,10 @@ 
         """return file flags"""
         return ''
 
+    def printfiles(self, ui, m, fm, fmt):
+        """handle the files command for this subrepo"""
+        return 1
+
     def archive(self, archiver, prefix, match=None):
         if match is not None:
             files = [f for f in self.files() if match(f)]
@@ -848,6 +852,17 @@ 
         ctx = self._repo[rev]
         return ctx.flags(name)
 
+    @annotatesubrepoerror
+    def printfiles(self, ui, m, fm, fmt):
+        # If the parent context is a workingctx, use the workingctx here for
+        # consistency.
+        if self._ctx.rev() is None:
+            ctx = self._repo[None]
+        else:
+            rev = self._state[1]
+            ctx = self._repo[rev]
+        return cmdutil.files(ui, ctx, m, fm, fmt, True)
+
     def walk(self, match):
         ctx = self._repo[None]
         return ctx.walk(match)
diff --git a/tests/test-completion.t b/tests/test-completion.t
--- a/tests/test-completion.t
+++ b/tests/test-completion.t
@@ -262,7 +262,7 @@ 
   debugsuccessorssets: 
   debugwalk: include, exclude
   debugwireargs: three, four, five, ssh, remotecmd, insecure
-  files: rev, print0, include, exclude, template
+  files: rev, print0, include, exclude, template, subrepos
   graft: rev, continue, edit, log, force, currentdate, currentuser, date, user, tool, dry-run
   grep: print0, all, text, follow, ignore-case, files-with-matches, line-number, rev, user, date, include, exclude
   heads: rev, topo, active, closed, style, template
diff --git a/tests/test-subrepo-deep-nested-change.t b/tests/test-subrepo-deep-nested-change.t
--- a/tests/test-subrepo-deep-nested-change.t
+++ b/tests/test-subrepo-deep-nested-change.t
@@ -186,6 +186,24 @@ 
   adding foo/bar/abc
   committing subrepository sub1
   committing subrepository sub1/sub2 (glob)
+
+  $ hg forget sub1/sub2/sub2
+  $ echo x > sub1/sub2/x.txt
+  $ hg add sub1/sub2/x.txt
+
+Files sees uncommitted adds and removes in subrepos
+  $ hg files -S
+  .hgsub
+  .hgsubstate
+  foo/bar/abc (glob)
+  main
+  sub1/.hgsub (glob)
+  sub1/.hgsubstate (glob)
+  sub1/foo (glob)
+  sub1/sub1 (glob)
+  sub1/sub2/folder/bar (glob)
+  sub1/sub2/x.txt (glob)
+
   $ hg rollback -q
   $ hg up -Cq
 
@@ -393,6 +411,7 @@ 
   R sub1/sub2/test.txt
   ? foo/bar/abc
   ? sub1/sub2/untracked.txt
+  ? sub1/sub2/x.txt
   $ hg add sub1/sub2
   $ hg ci -Sqm 'forget testing'
 
diff --git a/tests/test-subrepo.t b/tests/test-subrepo.t
--- a/tests/test-subrepo.t
+++ b/tests/test-subrepo.t
@@ -25,8 +25,13 @@ 
   abort: can't commit subrepos without .hgsub
   [255]
 
+  $ hg -R s add s/a
+  $ hg files -S
+  .hgsub
+  a
+  s/a (glob)
+
   $ hg -R s ci -Ams0
-  adding a
   $ hg sum
   parent: 0:f7b1eb17ad24 tip
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