done

libs/cli/tests/unit_tests/test_engine_runtime_mode.py

@@ -0,0 +1,99 @@
+import json
+import pathlib
+
+import click
+import pytest
+
+from langgraph_cli.engine_runtime_mode import resolve_engine_runtime_mode
+
+
+def _write_config(
+    tmp_path: pathlib.Path,
+    *,
+    python_version: str | None = "3.11",
+    node_version: str | None = None,
+) -> pathlib.Path:
+    cfg: dict = {"dependencies": ["."], "graphs": {"agent": "agent.py:graph"}}
+    if python_version is not None:
+        cfg["python_version"] = python_version
+    if node_version is not None:
+        cfg["node_version"] = node_version
+    path = tmp_path / "langgraph.json"
+    path.write_text(json.dumps(cfg))
+    return path
+
+
+class TestResolveEngineRuntimeMode:
+    # -- cli_param == "distributed" -------------------------------------------
+
+    def test_distributed_explicit_new_version(self, tmp_path: pathlib.Path) -> None:
+        path = _write_config(tmp_path)
+        assert (
+            resolve_engine_runtime_mode(path, "0.7.68", "distributed") == "distributed"
+        )
+
+    def test_distributed_explicit_old_version_raises(
+        self, tmp_path: pathlib.Path
+    ) -> None:
+        path = _write_config(tmp_path)
+        with pytest.raises(click.ClickException, match="0.7.67"):
+            resolve_engine_runtime_mode(path, "0.7.67", "distributed")
+
+    def test_distributed_explicit_js_raises(self, tmp_path: pathlib.Path) -> None:
+        path = _write_config(tmp_path, python_version=None, node_version="20")
+        with pytest.raises(click.ClickException, match="JavaScript"):
+            resolve_engine_runtime_mode(path, "0.8.0", "distributed")
+
+    def test_distributed_explicit_js_and_old_version_raises(
+        self, tmp_path: pathlib.Path
+    ) -> None:
+        path = _write_config(tmp_path, python_version=None, node_version="20")
+        with pytest.raises(click.ClickException, match="JavaScript.*0.7.60"):
+            resolve_engine_runtime_mode(path, "0.7.60", "distributed")
+
+    # -- cli_param == "combined_queue_worker" ----------------------------------
+
+    def test_combined_explicit(self, tmp_path: pathlib.Path) -> None:
+        path = _write_config(tmp_path)
+        assert (
+            resolve_engine_runtime_mode(path, "0.8.0", "combined_queue_worker")
+            == "combined_queue_worker"
+        )
+
+    def test_combined_explicit_old_version(self, tmp_path: pathlib.Path) -> None:
+        path = _write_config(tmp_path)
+        assert (
+            resolve_engine_runtime_mode(path, "0.7.67", "combined_queue_worker")
+            == "combined_queue_worker"
+        )
+
+    # -- cli_param is None (default) -------------------------------------------
+
+    def test_default_is_distributed(self, tmp_path: pathlib.Path) -> None:
+        path = _write_config(tmp_path)
+        assert resolve_engine_runtime_mode(path, "0.8.0", None) == "distributed"
+
+    def test_default_old_version(self, tmp_path: pathlib.Path) -> None:
+        path = _write_config(tmp_path)
+        assert resolve_engine_runtime_mode(path, "0.7.67", None) == "distributed"
+
+    def test_default_js(self, tmp_path: pathlib.Path) -> None:
+        path = _write_config(tmp_path, python_version=None, node_version="20")
+        assert resolve_engine_runtime_mode(path, "0.8.0", None) == "distributed"
+
+    # -- edge: version boundary ------------------------------------------------
+
+    def test_version_boundary_0_7_67_blocks_distributed(
+        self, tmp_path: pathlib.Path
+    ) -> None:
+        path = _write_config(tmp_path)
+        with pytest.raises(click.ClickException):
+            resolve_engine_runtime_mode(path, "0.7.67", "distributed")
+
+    def test_version_boundary_0_7_68_allows_distributed(
+        self, tmp_path: pathlib.Path
+    ) -> None:
+        path = _write_config(tmp_path)
+        assert (
+            resolve_engine_runtime_mode(path, "0.7.68", "distributed") == "distributed"
+        )