Fix repo trees, add fast path. am: 242574e9d9 am: 44becffcf9 am: 5c351f372d

Original change: https://android-review.googlesource.com/c/platform/tools/external_updater/+/2513908

Change-Id: I5cca38670d0d68034ac004c4e8c510f1bcbdac58
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

2 files changed, 66 insertions, 1 deletions

diff --git a/git_utils.py b/git_utils.py
index 75a2a24..c8e50b6 100644
--- a/git_utils.py
+++ b/git_utils.py
@@ -15,6 +15,7 @@
 
 import datetime
 import re
+import shutil
 import subprocess
 from pathlib import Path
 
@@ -202,7 +203,12 @@ def tree_uses_pore(proj_path: Path) -> bool:
 
     https://github.com/jmgao/pore
     """
-    if proj_path == proj_path.root:
+    if shutil.which("pore") is None:
+        # Fast path for users that don't have pore installed, since that's almost
+        # everyone.
+        return False
+
+    if proj_path == Path(proj_path.root):
         return False
     if (proj_path / ".pore").exists():
         return True
diff --git a/test_git_utils.py b/test_git_utils.py
new file mode 100644
index 0000000..c9d948a
--- /dev/null
+++ b/test_git_utils.py
@@ -0,0 +1,59 @@
+#
+# Copyright (C) 2023 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the 'License');
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an 'AS IS' BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+"""Tests for the git_utils module."""
+from pathlib import Path
+import pytest
+from pytest_mock import MockerFixture
+
+from git_utils import tree_uses_pore
+
+
+@pytest.fixture(name="repo_tree")
+def fixture_repo_tree(tmp_path: Path) -> Path:
+    """Fixture for a repo tree."""
+    (tmp_path / ".repo").write_text("")
+    (tmp_path / "external/foobar").mkdir(parents=True)
+    return tmp_path
+
+
+@pytest.fixture(name="pore_tree")
+def fixture_pore_tree(repo_tree: Path) -> Path:
+    """Fixture for a pore tree."""
+    (repo_tree / ".pore").write_text("")
+    return repo_tree
+
+
+def test_tree_uses_pore_fast_path(tmp_path: Path, mocker: MockerFixture) -> None:
+    """Tests that the fast-path does not recurse."""
+    which_mock = mocker.patch("shutil.which")
+    which_mock.return_value = None
+    path_parent_mock = mocker.patch("pathlib.Path.parent")
+    assert not tree_uses_pore(tmp_path)
+    path_parent_mock.assert_not_called()
+
+
+def test_tree_uses_pore_identifies_pore_trees(pore_tree: Path, mocker: MockerFixture) -> None:
+    """Tests that a pore tree is correctly identified."""
+    which_mock = mocker.patch("shutil.which")
+    which_mock.return_value = Path("pore")
+    assert tree_uses_pore(pore_tree)
+
+
+def test_tree_uses_pore_identifies_repo_trees(repo_tree: Path, mocker: MockerFixture) -> None:
+    """Tests that a repo tree is correctly identified."""
+    which_mock = mocker.patch("shutil.which")
+    which_mock.return_value = Path("pore")
+    assert not tree_uses_pore(repo_tree)