files: add support for log-like template keywords and functions

Note that the ctx does not point to the revision where the file was
last changed, but the revision specified by -rREV option.

mercurial/cmdutil.py

@@ -2144,6 +2144,7 b' def files(ui, ctx, m, fm, fmt, subrepos)'
     needsfctx = ui.verbose or {'size', 'flags'} & fm.datahint()
     for f in ctx.matches(m):
         fm.startitem()
+        fm.context(ctx=ctx)
         if needsfctx:
             fc = ctx[f]
             fm.write('size flags', '% 10d % 1s ', fc.size(), fc.flags())

tests/test-manifest.t

@@ -41,6 +41,10 b' The next call is expected to return noth'
   a 2 
   b/a 2 x
   l 1 l
+  $ hg files -T '{path} {node|shortest}\n' -r.
+  a 5bdc
+  b/a 5bdc
+  l 5bdc
 
   $ hg manifest -v
   644   a