internal: make release to chdir before looking for version markers (bazel-contrib#3342)

The release tool wasn't determining the next version correctly because
it was
in the wrong directory when that logic ran. To fix, chdir before that
logic kicks off.

Author: rickeylev

tests/tools/private/release/release_test.py

@@ -210,5 +210,62 @@ def test_get_latest_version_only_rc_tags(self, mock_get_tags):
             releaser.get_latest_version()
 
 
+class DetermineNextVersionTest(unittest.TestCase):
+    def setUp(self):
+        self.tmpdir = pathlib.Path(tempfile.mkdtemp())
+        self.original_cwd = os.getcwd()
+        self.addCleanup(shutil.rmtree, self.tmpdir)
+
+        os.chdir(self.tmpdir)
+        # NOTE: On windows, this must be done before files are deleted.
+        self.addCleanup(os.chdir, self.original_cwd)
+
+        self.mock_get_latest_version = patch(
+            "tools.private.release.release.get_latest_version"
+        ).start()
+        self.addCleanup(patch.stopall)
+
+    def test_no_markers(self):
+        (self.tmpdir / "mock_file.bzl").write_text("no markers here")
+        self.mock_get_latest_version.return_value = "1.2.3"
+
+        next_version = releaser.determine_next_version()
+
+        self.assertEqual(next_version, "1.2.4")
+
+    def test_only_patch(self):
+        (self.tmpdir / "mock_file.bzl").write_text(
+            ":::{versionchanged} VERSION_NEXT_PATCH"
+        )
+        self.mock_get_latest_version.return_value = "1.2.3"
+
+        next_version = releaser.determine_next_version()
+
+        self.assertEqual(next_version, "1.2.4")
+
+    def test_only_feature(self):
+        (self.tmpdir / "mock_file.bzl").write_text(
+            ":::{versionadded} VERSION_NEXT_FEATURE"
+        )
+        self.mock_get_latest_version.return_value = "1.2.3"
+
+        next_version = releaser.determine_next_version()
+
+        self.assertEqual(next_version, "1.3.0")
+
+    def test_both_markers(self):
+        (self.tmpdir / "mock_file_patch.bzl").write_text(
+            ":::{versionchanged} VERSION_NEXT_PATCH"
+        )
+        (self.tmpdir / "mock_file_feature.bzl").write_text(
+            ":::{versionadded} VERSION_NEXT_FEATURE"
+        )
+        self.mock_get_latest_version.return_value = "1.2.3"
+
+        next_version = releaser.determine_next_version()
+
+        self.assertEqual(next_version, "1.3.0")
+
+
 if __name__ == "__main__":
     unittest.main()

tools/private/release/release.py

@@ -170,6 +170,10 @@ def create_parser():
 
 
 def main():
+    # Change to the workspace root so the script can be run using `bazel run`
+    if "BUILD_WORKSPACE_DIRECTORY" in os.environ:
+        os.chdir(os.environ["BUILD_WORKSPACE_DIRECTORY"])
+
     parser = create_parser()
     args = parser.parse_args()
 
@@ -179,10 +183,6 @@ def main():
         version = determine_next_version()
         print(f"Determined next version: {version}")
 
-    # Change to the workspace root so the script can be run using `bazel run`
-    if "BUILD_WORKSPACE_DIRECTORY" in os.environ:
-        os.chdir(os.environ["BUILD_WORKSPACE_DIRECTORY"])
-
     print("Updating changelog ...")
     release_date = datetime.date.today().strftime("%Y-%m-%d")
     update_changelog(version, release_date)