refactor(01-02): add comprehensive tests for full coverage

- Add tests for WorkflowState methods (mark_step_started, mark_step_completed, mark_step_failed)
- Add tests for StepResult schema
- Add tests for StepDefinition schema with dependencies
- Achieve 100% test coverage on kb_pipeline/schemas.py
- Total 37 tests passing

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tests/test_pipeline/test_schemas.py

@@ -215,6 +215,157 @@ class TestWorkflowState:
         assert state.is_step_completed("fetch_metadata") is True
 
 
+class TestWorkflowStateMethods:
+    """测试 WorkflowState 方法"""
+
+    def test_mark_step_started(self):
+        """mark_step_started 正确设置步骤状态"""
+        from kb_pipeline.schemas import WorkflowState, StepStatus
+
+        state = WorkflowState(
+            content_id="BV1test",
+            platform="bilibili",
+            source_url="https://test.com"
+        )
+
+        state.mark_step_started("fetch_metadata")
+
+        assert "fetch_metadata" in state.steps
+        assert state.steps["fetch_metadata"].status == StepStatus.RUNNING
+        assert state.steps["fetch_metadata"].started_at is not None
+
+    def test_mark_step_completed_existing_step(self):
+        """mark_step_completed 更新已存在的步骤"""
+        from kb_pipeline.schemas import WorkflowState, StepStatus
+
+        state = WorkflowState(
+            content_id="BV1test",
+            platform="bilibili",
+            source_url="https://test.com"
+        )
+
+        state.mark_step_started("fetch_metadata")
+        state.mark_step_completed("fetch_metadata", "成功获取元数据")
+
+        assert state.steps["fetch_metadata"].status == StepStatus.COMPLETED
+        assert state.steps["fetch_metadata"].completed_at is not None
+        assert state.steps["fetch_metadata"].output_summary == "成功获取元数据"
+
+    def test_mark_step_completed_new_step(self):
+        """mark_step_completed 创建新步骤记录"""
+        from kb_pipeline.schemas import WorkflowState, StepStatus
+
+        state = WorkflowState(
+            content_id="BV1test",
+            platform="bilibili",
+            source_url="https://test.com"
+        )
+
+        state.mark_step_completed("download_video", "视频下载完成")
+
+        assert "download_video" in state.steps
+        assert state.steps["download_video"].status == StepStatus.COMPLETED
+        assert state.steps["download_video"].output_summary == "视频下载完成"
+
+    def test_mark_step_failed_existing_step(self):
+        """mark_step_failed 更新已存在的步骤为失败"""
+        from kb_pipeline.schemas import WorkflowState, StepStatus
+
+        state = WorkflowState(
+            content_id="BV1test",
+            platform="bilibili",
+            source_url="https://test.com"
+        )
+
+        state.mark_step_started("fetch_metadata")
+        state.mark_step_failed("fetch_metadata", "网络错误")
+
+        assert state.steps["fetch_metadata"].status == StepStatus.FAILED
+        assert state.steps["fetch_metadata"].error_message == "网络错误"
+        assert state.steps["fetch_metadata"].completed_at is not None
+
+    def test_mark_step_failed_new_step(self):
+        """mark_step_failed 创建新的失败步骤记录"""
+        from kb_pipeline.schemas import WorkflowState, StepStatus
+
+        state = WorkflowState(
+            content_id="BV1test",
+            platform="bilibili",
+            source_url="https://test.com"
+        )
+
+        state.mark_step_failed("download_video", "文件不存在")
+
+        assert "download_video" in state.steps
+        assert state.steps["download_video"].status == StepStatus.FAILED
+        assert state.steps["download_video"].error_message == "文件不存在"
+
+
+class TestStepResult:
+    """测试 StepResult Schema"""
+
+    def test_step_result_creation(self):
+        """StepResult 正确创建"""
+        from kb_pipeline.schemas import StepResult, StepInput, StepStatus
+
+        input_data = StepInput(content_id="BV1test", platform="bilibili")
+        result = StepResult(step_name="fetch_metadata", input_data=input_data)
+
+        assert result.step_name == "fetch_metadata"
+        assert result.status == StepStatus.PENDING
+        assert result.output_data is None
+
+    def test_step_result_with_output(self):
+        """StepResult 包含输出数据"""
+        from kb_pipeline.schemas import StepResult, StepInput, StepOutput, StepStatus
+
+        input_data = StepInput(content_id="BV1test", platform="bilibili")
+        output_data = StepOutput(success=True)
+        result = StepResult(
+            step_name="fetch_metadata",
+            input_data=input_data,
+            output_data=output_data,
+            status=StepStatus.COMPLETED
+        )
+
+        assert result.output_data is not None
+        assert result.output_data.success is True
+
+
+class TestStepDefinition:
+    """测试 StepDefinition Schema"""
+
+    def test_step_definition_creation(self):
+        """StepDefinition 正确创建"""
+        from kb_pipeline.schemas import StepDefinition, StepInput, StepOutput
+
+        definition = StepDefinition(
+            step_name="fetch_metadata",
+            description="获取视频元数据",
+            input_schema=StepInput,
+            output_schema=StepOutput
+        )
+
+        assert definition.step_name == "fetch_metadata"
+        assert definition.description == "获取视频元数据"
+        assert definition.dependencies == []
+
+    def test_step_definition_with_dependencies(self):
+        """StepDefinition 包含依赖"""
+        from kb_pipeline.schemas import StepDefinition, StepInput, StepOutput
+
+        definition = StepDefinition(
+            step_name="transcribe_audio",
+            description="转录音频",
+            input_schema=StepInput,
+            output_schema=StepOutput,
+            dependencies=["download_video", "extract_audio"]
+        )
+
+        assert len(definition.dependencies) == 2
+        assert "download_video" in definition.dependencies
+
+
 class TestSchemaValidation:
     """测试 Pydantic 验证"""