fix(api): fix fail branch functionality for WorkflowTool (#15966)

api/tests/unit_tests/core/tools/workflow_as_tool/test_tool.py

@@ -0,0 +1,49 @@
+import pytest
+
+from core.app.entities.app_invoke_entities import InvokeFrom
+from core.tools.__base.tool_runtime import ToolRuntime
+from core.tools.entities.common_entities import I18nObject
+from core.tools.entities.tool_entities import ToolEntity, ToolIdentity
+from core.tools.errors import ToolInvokeError
+from core.tools.workflow_as_tool.tool import WorkflowTool
+
+
+def test_workflow_tool_should_raise_tool_invoke_error_when_result_has_error_field(monkeypatch):
+    """Ensure that WorkflowTool will throw a `ToolInvokeError` exception when
+    `WorkflowAppGenerator.generate` returns a result with `error` key inside
+    the `data` element.
+    """
+    entity = ToolEntity(
+        identity=ToolIdentity(author="test", name="test tool", label=I18nObject(en_US="test tool"), provider="test"),
+        parameters=[],
+        description=None,
+        output_schema=None,
+        has_runtime_parameters=False,
+    )
+    runtime = ToolRuntime(tenant_id="test_tool", invoke_from=InvokeFrom.EXPLORE)
+    tool = WorkflowTool(
+        workflow_app_id="",
+        workflow_as_tool_id="",
+        version="1",
+        workflow_entities={},
+        workflow_call_depth=1,
+        entity=entity,
+        runtime=runtime,
+    )
+
+    # needs to patch those methods to avoid database access.
+    monkeypatch.setattr(tool, "_get_app", lambda *args, **kwargs: None)
+    monkeypatch.setattr(tool, "_get_workflow", lambda *args, **kwargs: None)
+    monkeypatch.setattr(tool, "_get_user", lambda *args, **kwargs: None)
+
+    # replace `WorkflowAppGenerator.generate` 's return value.
+    monkeypatch.setattr(
+        "core.app.apps.workflow.app_generator.WorkflowAppGenerator.generate",
+        lambda *args, **kwargs: {"data": {"error": "oops"}},
+    )
+
+    with pytest.raises(ToolInvokeError) as exc_info:
+        # WorkflowTool always returns a generator, so we need to iterate to
+        # actually `run` the tool.
+        list(tool.invoke("test_user", {}))
+    assert exc_info.value.args == ("oops",)