subrepo: add basic support to hgsubrepo for the files command Paths into the subrepo are not yet supported. The need to use the workingctx in the subrepo will likely be used more in the future, with the proposed working directory revset symbol. It is also needed with archive, if that code is to be reused to support 'extdiff -S'. Unfortunately, it doesn't seem possible to put the smarts in subrepo.subrepo(), as it breaks various status and diff tests. I opted not to pass the desired revision into the subrepo method explicitly, because the only ones that do pass an explicit revision are methods like status and diff, which actually operate on two contexts- the subrepo state and the explicitly passed revision.

--- a/mercurial/help/subrepos.txt	Wed Mar 18 22:56:41 2015 -0400
+++ b/mercurial/help/subrepos.txt	Wed Mar 18 23:03:41 2015 -0400
@@ -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.