treemanifest: add walksubtrees api
authorDurham Goode <durham@fb.com>
Mon, 10 Apr 2017 13:07:47 -0700
changeset 31876 94c1d3c1aea2
parent 31875 b6d792a9bd11
child 31877 14c5a7637ecc
treemanifest: add walksubtrees api Adds a new function to treemanifest that allows walking over the directories in the tree. Currently it only accepts a matcher to prune the walk, but in the future it will also accept a list of trees and will only walk over subtrees that differ from the versions in the list. This will be useful for identifying what parts of the tree are new to this revision, which is useful when deciding the minimal set of trees to send to a client given that they have a certain tree already. Since this is intended for an extension to use, the only current consumer is a test. In the future this function may be useful for implementing other algorithms like diff and changegroup generation.
mercurial/manifest.py
tests/test-manifest.py
--- a/mercurial/manifest.py	Tue Apr 11 23:12:14 2017 +0900
+++ b/mercurial/manifest.py	Mon Apr 10 13:07:47 2017 -0700
@@ -1155,6 +1155,22 @@
                 subp1, subp2 = subp2, subp1
             writesubtree(subm, subp1, subp2)
 
+    def walksubtrees(self, matcher=None):
+        """Returns an iterator of the subtrees of this manifest, including this
+        manifest itself.
+
+        If `matcher` is provided, it only returns subtrees that match.
+        """
+        if matcher and not matcher.visitdir(self._dir[:-1] or '.'):
+            return
+        if not matcher or matcher(self._dir[:-1]):
+            yield self
+
+        self._load()
+        for d, subm in self._dirs.iteritems():
+            for subtree in subm.walksubtrees(matcher=matcher):
+                yield subtree
+
 class manifestrevlog(revlog.revlog):
     '''A revlog that stores manifest texts. This is responsible for caching the
     full-text manifest contents.
--- a/tests/test-manifest.py	Tue Apr 11 23:12:14 2017 +0900
+++ b/tests/test-manifest.py	Mon Apr 10 13:07:47 2017 -0700
@@ -467,5 +467,21 @@
     def parsemanifest(self, text):
         return manifestmod.treemanifest('', text)
 
+    def testWalkSubtrees(self):
+        m = self.parsemanifest(A_DEEPER_MANIFEST)
+
+        dirs = [s._dir for s in m.walksubtrees()]
+        self.assertEqual(
+            sorted(['', 'a/', 'a/c/', 'a/d/', 'a/b/', 'a/b/c/', 'a/b/d/']),
+            sorted(dirs)
+        )
+
+        match = matchmod.match('/', '', ['path:a/b/'])
+        dirs = [s._dir for s in m.walksubtrees(matcher=match)]
+        self.assertEqual(
+            sorted(['a/b/', 'a/b/c/', 'a/b/d/']),
+            sorted(dirs)
+        )
+
 if __name__ == '__main__':
     silenttestrunner.main(__name__)