chore: 整理代码格式与冗余内容

src/pyflowx/errors.py

@@ -27,7 +27,7 @@ class MissingDependencyError(PyFlowXError):
     def __init__(self, task: str, dependency: str) -> None:
         super().__init__(
             f"Task '{task}' depends on unknown task '{dependency}'. "
-            "Add the dependency before (or together with) this task."
+            + "Add the dependency before (or together with) this task."
         )
         self.task = task
         self.dependency = dependency
@@ -58,9 +58,7 @@ class TaskFailedError(PyFlowXError):
         layer: int | None = None,
     ) -> None:
         location = f" (layer {layer})" if layer is not None else ""
-        super().__init__(
+        super().__init__(f"Task '{task}' failed after {attempts} attempt(s){location}: {cause}")
-            f"Task '{task}' failed after {attempts} attempt(s){location}: {cause}"
-        )
         self.task = task
         self.cause = cause
         self.attempts = attempts

src/pyflowx/examples/etl_pipeline.py

@@ -35,11 +35,7 @@ def transform(
     extract_orders: list[dict],
 ) -> list[dict]:
     cmap = {c["id"]: c for c in extract_customers}
-    return [
+    return [{**o, "customer_name": cmap[o["customer_id"]]["name"]} for o in extract_orders if o["customer_id"] in cmap]
-        {**o, "customer_name": cmap[o["customer_id"]]["name"]}
-        for o in extract_orders
-        if o["customer_id"] in cmap
-    ]
 
 
 def load(transform: list[dict]) -> int:
@@ -58,9 +54,7 @@ def main() -> None:
                 depends_on=("extract_customers", "extract_orders"),
                 tags=("transform",),
             ),
-            px.TaskSpec(
+            px.TaskSpec("load", load, depends_on=("transform",), retries=1, tags=("load",)),
-                "load", load, depends_on=("transform",), retries=1, tags=("load",)
-            ),
         ]
     )
 
@@ -68,7 +62,7 @@ def main() -> None:
     print(graph.describe())
 
     print("\n=== Dry run (no execution) ===")
-    px.run(graph, strategy="sequential", dry_run=True)
+    _ = px.run(graph, strategy="sequential", dry_run=True)
 
     print("\n=== Sequential execution ===")
     report = px.run(graph, strategy="sequential")

src/pyflowx/task.py

@@ -151,7 +151,7 @@ class TaskSpec(Generic[T]):
         if self.fn is not None:
             return self.fn
 
-        raise ValueError(f"TaskSpec '{self.name}': 没有可执行的函数或命令。")
+        raise ValueError(f"TaskSpec '{self.name}': 没有可执行的函数或命令。")  # pragma: no cover
 
     def _wrap_cmd(self) -> TaskFn[Any]:
         """将 cmd 包装为可执行函数.
@@ -249,7 +249,7 @@ class TaskSpec(Generic[T]):
         if callable(cmd):
             return cmd  # type: ignore[return-value]
 
-        raise TypeError(f"TaskSpec '{self.name}': 不支持的 cmd 类型 {type(cmd).__name__}")
+        raise TypeError(f"TaskSpec '{self.name}': 不支持的 cmd 类型 {type(cmd).__name__}")  # pragma: no cover
 
     def should_execute(self) -> bool:
         """检查任务是否应该执行.