feat(contributor-scan): retain first-party JavaScript tests in graphs

tests/test_frontend_retention.py

@@ -0,0 +1,31 @@
+"""Explicit frontend input policy must survive both subprocess paths."""
+
+from openultrasast.cpg.backend import JoernBackend
+
+
+def test_first_party_tests_enabled_by_backend(monkeypatch):
+    monkeypatch.setenv("OUSAST_INCLUDE_TESTS", "0")
+    assert JoernBackend()._jvm_env()["OUSAST_INCLUDE_TESTS"] == "1"
+
+
+def test_retention_can_be_disabled_explicitly():
+    assert JoernBackend(include_tests=False)._jvm_env()["OUSAST_INCLUDE_TESTS"] == "0"
+
+
+def test_builder_rejects_unrecognized_dependency_before_download(tmp_path):
+    import importlib.util
+    from pathlib import Path
+
+    import pytest
+
+    spec = importlib.util.spec_from_file_location("retention_builder", Path("ops/frontend-retention/install.py"))
+    assert spec is not None and spec.loader is not None
+    builder = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(builder)
+    jar = tmp_path / "frontends/jssrc2cpg/lib/io.joern.jssrc2cpg-4.0.625.jar"
+    jar.parent.mkdir(parents=True)
+    jar.write_bytes(b"different dependency")
+    with pytest.raises(ValueError, match="pristine Joern"):
+        builder.build(tmp_path)
+    assert jar.read_bytes() == b"different dependency"
+    assert not (tmp_path / "ousast-frontend-retention-v1").exists()