Introduce eden debug hg_get_dirstate_tuple.

Summary:
This is a convenient way to test the `hgGetDirstateTuple()` endpoint in
`eden.thrift`.

Reviewed By: quark-zju, wez

Differential Revision: D5654237

fbshipit-source-id: 0b285e056002d4556733a53293582345f36780b2

eden/cli/TARGETS

@@ -29,6 +29,7 @@ python_library(
     ],
     deps = [
         ":lib",
+        "@/eden/fs/inodes:hgdirstate-py",
         "@/eden/fs/inodes:serialization-py",
     ],
 )

eden/cli/debug.py

@@ -15,6 +15,7 @@ import sys
 from typing import List, Tuple
 
 from facebook.eden.overlay.ttypes import OverlayDir
+import facebook.hgdirstate.ttypes as hgdirstate
 
 from . import cmd_util
 
@@ -169,6 +170,26 @@ def _print_inode_info(inode_info):
         print(line)
 
 
+def do_hg_get_dirstate_tuple(args: argparse.Namespace):
+    config = cmd_util.create_config(args)
+    mount, rel_path = get_mount_path(args.path)
+    with config.get_thrift_client() as client:
+        dirstate_tuple = client.hgGetDirstateTuple(mount, rel_path)
+
+    status = hgdirstate.DirstateNonnormalFileStatus._VALUES_TO_NAMES[
+        dirstate_tuple.status
+    ]
+    merge_state = hgdirstate.DirstateMergeState._VALUES_TO_NAMES[
+        dirstate_tuple.mergeState
+    ]
+    print(f'''\
+{rel_path}
+    status = {status}
+    mode = {oct(dirstate_tuple.mode)}
+    mergeState = {merge_state}\
+''')
+
+
 def do_inode(args: argparse.Namespace):
     config = cmd_util.create_config(args)
     mount, rel_path = get_mount_path(args.path)
@@ -372,6 +393,13 @@ def setup_argparse(parser: argparse.ArgumentParser):
     parser.add_argument('id', help='The blob ID')
     parser.set_defaults(func=do_blobmeta)
 
+    parser = subparsers.add_parser(
+        'hg_get_dirstate_tuple', help='Dirstate status for file')
+    parser.add_argument(
+        'path',
+        help='The path to the file whose status should be queried.')
+    parser.set_defaults(func=do_hg_get_dirstate_tuple)
+
     parser = subparsers.add_parser(
         'inode', help='Show data about loaded inodes')
     parser.add_argument(

eden/integration/debug_hg_get_dirstate_tuple_test.py

@@ -0,0 +1,32 @@
+#!/usr/bin/env python3
+#
+# Copyright (c) 2016-present, Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree. An additional grant
+# of patent rights can be found in the PATENTS file in the same directory.
+
+from .lib import testcase
+import os
+from textwrap import dedent
+
+
+@testcase.eden_repo_test
+class DebugHgGetDirstateTupleTest:
+    def populate_repo(self):
+        self.repo.write_file('hello', 'hola\n')
+        self.repo.write_file(os.path.join('dir', 'file'), 'blah\n')
+        self.repo.commit('Initial commit.')
+
+    def test_get_dirstate_tuple_normal_file(self):
+        output = self.eden.run_cmd(
+            'debug', 'hg_get_dirstate_tuple', os.path.join(self.mount, 'hello')
+        )
+        expected = dedent('''\
+        hello
+            status = Normal
+            mode = 0o100644
+            mergeState = NotApplicable
+        ''')
+        self.assertEqual(expected, output)