[ci][microcheck] recover the logic to compute new tests (#45495)

#45462 adds a new tests by
changing bazel rule instead of adding a new test file; this case can
only be covered by our previous logic of computing new tests; recover
this logic (in addition to the logic of computing new tests by looking
at changed test files)

Test:
- CI

---------

Signed-off-by: can <can@anyscale.com>

ci/ray_ci/test_tester.py

@@ -16,6 +16,7 @@
     _get_high_impact_test_targets,
     _get_flaky_test_targets,
     _get_tag_matcher,
+    _get_new_tests,
     _get_changed_files,
     _get_changed_tests,
     _get_human_specified_tests,
@@ -129,6 +130,9 @@ def test_get_test_targets() -> None:
         ), mock.patch(
             "ci.ray_ci.tester._get_changed_tests",
             return_value=set(),
+        ), mock.patch(
+            "ci.ray_ci.tester._get_new_tests",
+            return_value=set(),
         ):
             assert set(
                 _get_test_targets(
@@ -215,6 +219,7 @@ def test_get_high_impact_test_targets() -> None:
         {
             "input": [],
             "new_tests": set(),
+            "changed_tests": set(),
             "human_tests": set(),
             "output": set(),
         },
@@ -234,6 +239,7 @@ def test_get_high_impact_test_targets() -> None:
                 ),
             ],
             "new_tests": {"//core_new"},
+            "changed_tests": {"//core_new"},
             "human_tests": {"//human_test"},
             "output": {
                 "//core_good",
@@ -247,8 +253,11 @@ def test_get_high_impact_test_targets() -> None:
             "ray_release.test.Test.gen_high_impact_tests",
             return_value={"step": test["input"]},
         ), mock.patch(
-            "ci.ray_ci.tester._get_changed_tests",
+            "ci.ray_ci.tester._get_new_tests",
             return_value=test["new_tests"],
+        ), mock.patch(
+            "ci.ray_ci.tester._get_changed_tests",
+            return_value=test["changed_tests"],
         ), mock.patch(
             "ci.ray_ci.tester._get_human_specified_tests",
             return_value=test["human_tests"],
@@ -263,6 +272,17 @@ def test_get_high_impact_test_targets() -> None:
             )
 
 
+@mock.patch("subprocess.check_output")
+@mock.patch("ray_release.test.Test.gen_from_s3")
+def test_get_new_tests(mock_gen_from_s3, mock_check_output) -> None:
+    mock_gen_from_s3.return_value = [
+        _stub_test({"name": "linux://old_test_01"}),
+        _stub_test({"name": "linux://old_test_02"}),
+    ]
+    mock_check_output.return_value = b"//old_test_01\n//new_test"
+    assert _get_new_tests("linux") == {"//new_test"}
+
+
 @mock.patch.dict(
     os.environ,
     {"BUILDKITE_PULL_REQUEST_BASE_BRANCH": "base", "BUILDKITE_COMMIT": "commit"},

ci/ray_ci/tester.py

@@ -416,10 +416,15 @@ def _get_high_impact_test_targets(
         for test in itertools.chain.from_iterable(step_id_to_tests.values())
         if test.get_oncall() == team
     }
+    new_tests = _get_new_tests(os_prefix)
     changed_tests = _get_changed_tests()
     human_specified_tests = _get_human_specified_tests()
 
-    return high_impact_tests.union(changed_tests).union(human_specified_tests)
+    return (
+        high_impact_tests.union(new_tests)
+        .union(changed_tests)
+        .union(human_specified_tests)
+    )
 
 
 def _get_human_specified_tests() -> Set[str]:
@@ -445,6 +450,24 @@ def _get_human_specified_tests() -> Set[str]:
     return tests
 
 
+def _get_new_tests(prefix: str) -> Set[str]:
+    """
+    Get all local test targets that are not in database
+    """
+    local_test_targets = (
+        subprocess.check_output(
+            ["bazel", "query", "tests(//...)"],
+            cwd=bazel_workspace_dir,
+        )
+        .decode()
+        .strip()
+        .split(os.linesep)
+    )
+    db_test_targets = {test.get_target() for test in Test.gen_from_s3(prefix=prefix)}
+
+    return set(local_test_targets).difference(db_test_targets)
+
+
 def _get_changed_tests() -> Set[str]:
     """
     Get all changed tests in the current PR