test(runner): cover black-box group isolation

tests/cobol_testgen/test_run_external_groups.py

@@ -56,3 +56,50 @@ def test_run_external_groups_orchestration(tmp_path, monkeypatch):
     out_file = outdir / "black_box" / "g1" / "cobol" / "output" / "ZAN04W01"
     assert out_file.read_bytes() == b"A0000001"
     assert "bb_g1" in calls[0][1]
+
+
+def test_run_external_groups_isolates_groups(tmp_path, monkeypatch):
+    fields_dict = [
+        {"name": "R01APPL-ID", "level": 3, "pic": "X(8)",
+         "pic_info": {"type": "alphanumeric", "digits": 0, "decimal": 0,
+                      "length": 8, "signed": False}},
+    ]
+    fd_fields = {"R01INNFIL": ["R01APPL-ID"], "W01OUTFIL": ["R01APPL-ID"]}
+    select_info = {"R01INNFIL": {"assign": "ZAN04R01"},
+                   "W01OUTFIL": {"assign": "ZAN04W01",
+                                 "organization": "SEQUENTIAL"}}
+    open_dir = {"R01INNFIL": "INPUT", "W01OUTFIL": "OUTPUT"}
+    roles = {"R01APPL-ID": "input"}
+    field_to_fd = {"R01APPL-ID": "R01INNFIL"}
+
+    monkeypatch.setattr(runner, "compile_sub_modules", lambda *a, **k: [])
+    monkeypatch.setattr(runner, "compile_program",
+                        lambda *a, **k: str(tmp_path / "P.exe"))
+    monkeypatch.setattr(runner, "_discover_java", lambda *a, **k: None)
+
+    def fake_run_group(group, exe_path, temp_dir, log_dir=None):
+        if "g1" in group.name:
+            Path(temp_dir, "ZAN04W01").write_bytes(b"ONLY_G1")
+        return runner.GroupResult(name=group.name, returncode=0, passed=True)
+
+    monkeypatch.setattr(runner, "run_group", fake_run_group)
+
+    groups = [
+        BlackBoxGroup(label="g1",
+                      records=[{"R01APPL-ID": "A0000001"}],
+                      term_types=["normal"]),
+        BlackBoxGroup(label="g2",
+                      records=[{"R01APPL-ID": "A0000002"}],
+                      term_types=["normal"]),
+    ]
+    outdir = tmp_path / "out"
+    results, _ = runner.run_external_groups(
+        "P", str(outdir), str(tmp_path / "work"),
+        fields_dict, fd_fields, select_info, open_dir,
+        roles, field_to_fd, groups, source_dir=str(tmp_path / "src"),
+    )
+
+    assert [r.name for r in results] == ["P_black_box_g1", "P_black_box_g2"]
+    assert (outdir / "black_box" / "g1" / "cobol" / "output" / "ZAN04W01").exists()
+    assert not (outdir / "black_box" / "g2" / "cobol" / "output" / "ZAN04W01").exists()
+    assert not (tmp_path / "work" / "bb_g2" / "ZAN04W01").exists()