narrow: widen when files are excluded by sparse and not included by narrow

In a repo where some directories are included by narrow and the complement are
excluded by sparse, it was previously impossible to widen either because trying
to widen narrow would complain that the requested files are outside the sparse
checkout and trying to widen sparse would complain that the requested files are
outside the narrow checkout.

This changes the `hg tracked --addinclude` command to only actually update any
newly accessible files in the dirstate if they are also accessible via sparse.

Differential Revision: https://phab.mercurial-scm.org/D10734

mercurial/narrowspec.py

@@ -346,6 +346,9 b' def updateworkingcopy(repo, assumeclean='
         ds.drop(f)
 
     pctx = repo[b'.']
+
+    # only update added files that are in the sparse checkout
+    addedmatch = matchmod.intersectmatchers(addedmatch, sparse.matcher(repo))
     newfiles = [f for f in pctx.manifest().walk(addedmatch) if f not in ds]
     for f in newfiles:
         ds.normallookup(f)

tests/test-narrow-sparse.t

@@ -70,3 +70,37 b' XXX: we should have a flag in `hg debugs'
   treemanifest (tree !)
 
   $ hg debugrebuilddirstate
+
+We only make the following assertions for the flat test case since in the
+treemanifest test case debugsparse fails with "path ends in directory
+separator: outside/" which seems like a bug unrelated to the regression this is
+testing for.
+
+#if flat
+widening with both sparse and narrow is possible
+
+  $ cat >> .hg/hgrc <<EOF
+  > [extensions]
+  > sparse = 
+  > narrow = 
+  > EOF
+
+  $ hg debugsparse -X outside/f -X widest/f
+  $ hg tracked -q --addinclude outside/f
+  $ tree
+  .
+  `-- inside
+      `-- f
+  
+  1 directory, 1 file
+
+  $ hg debugsparse -d outside/f
+  $ tree
+  .
+  |-- inside
+  |   `-- f
+  `-- outside
+      `-- f
+  
+  2 directories, 2 files
+#endif