remotefilelog: import pruned-down remotefilelog extension from hg-experimental This is remotefilelog as of my recent patches for compatibility with current tip of hg, minus support for old versions of Mercurial and some FB-specific features like their treemanifest extension and fetching linkrev data from a patched phabricator. The file extutil.py moved from hgext3rd to remotefilelog. This is not yet ready to be landed, consider it a preview for now. Planned changes include: * replace lz4 with zstd * rename some capabilities, requirements and wireproto commands to mark them as experimental * consolidate bits of shallowutil with related functions (eg readfile) I'm certainly open to other (small) changes, but my rough mission is to land this largely as-is so we can use it as a model of the functionality we need going forward for lazy-fetching of file contents from a server. # no-check-commit because of a few foo_bar functions Differential Revision: https://phab.mercurial-scm.org/D4782

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/remotefilelog-getflogheads.py	Thu Sep 27 13:03:19 2018 -0400
@@ -0,0 +1,31 @@
+from __future__ import absolute_import
+
+from mercurial.i18n import _
+from mercurial import (
+    hg,
+    registrar,
+)
+
+cmdtable = {}
+command = registrar.command(cmdtable)
+
+@command('getflogheads',
+         [],
+         'path')
+def getflogheads(ui, repo, path):
+    """
+    Extension printing a remotefilelog's heads
+
+    Used for testing purpose
+    """
+
+    dest = repo.ui.expandpath('default')
+    peer = hg.peer(repo, {}, dest)
+
+    flogheads = peer.getflogheads(path)
+
+    if flogheads:
+        for head in flogheads:
+            ui.write(head + '\n')
+    else:
+        ui.write(_('EMPTY\n'))