Refactor test cases for improved readability and consistency

- Added blank lines for better separation of test cases in multiple test files.
- Reformatted event handling in tests for clarity and consistency.
- Ensured consistent use of multi-line formatting for dictionary arguments in event handling.
- Improved assertions and test descriptions for better understanding.
- Updated test cases across various modules including test_stream_state, test_stream_utils, test_summarization, test_thread_selector, test_tool_error_handler, test_tui_widgets, test_ui_runtime, and test_wechat_channel.

EvoScientist/stream/emitter.py

@@ -11,6 +11,7 @@ from typing import Any, Dict
 @dataclass
 class StreamEvent:
     """Unified stream event."""
+
     type: str
     data: Dict[str, Any]
 
@@ -21,7 +22,9 @@ class StreamEventEmitter:
     @staticmethod
     def thinking(content: str, thinking_id: int = 0) -> StreamEvent:
         """Thinking content event."""
-        return StreamEvent("thinking", {"type": "thinking", "content": content, "id": thinking_id})
+        return StreamEvent(
+            "thinking", {"type": "thinking", "content": content, "id": thinking_id}
+        )
 
     @staticmethod
     def text(content: str) -> StreamEvent:
@@ -31,52 +34,67 @@ class StreamEventEmitter:
     @staticmethod
     def tool_call(name: str, args: Dict[str, Any], tool_id: str = "") -> StreamEvent:
         """Tool call event."""
-        return StreamEvent("tool_call", {"type": "tool_call", "name": name, "args": args, "id": tool_id})
+        return StreamEvent(
+            "tool_call",
+            {"type": "tool_call", "name": name, "args": args, "id": tool_id},
+        )
 
     @staticmethod
     def tool_result(name: str, content: str, success: bool = True) -> StreamEvent:
         """Tool result event."""
-        return StreamEvent("tool_result", {
-            "type": "tool_result",
-            "name": name,
-            "content": content,
-            "success": success,
-        })
+        return StreamEvent(
+            "tool_result",
+            {
+                "type": "tool_result",
+                "name": name,
+                "content": content,
+                "success": success,
+            },
+        )
 
     @staticmethod
     def subagent_start(name: str, description: str) -> StreamEvent:
         """Sub-agent delegation started."""
-        return StreamEvent("subagent_start", {
-            "type": "subagent_start",
-            "name": name,
-            "description": description,
-        })
+        return StreamEvent(
+            "subagent_start",
+            {
+                "type": "subagent_start",
+                "name": name,
+                "description": description,
+            },
+        )
 
     @staticmethod
     def subagent_tool_call(
         subagent: str, name: str, args: Dict[str, Any], tool_id: str = ""
     ) -> StreamEvent:
         """Tool call from inside a sub-agent."""
-        return StreamEvent("subagent_tool_call", {
-            "type": "subagent_tool_call",
-            "subagent": subagent,
-            "name": name,
-            "args": args,
-            "id": tool_id,
-        })
+        return StreamEvent(
+            "subagent_tool_call",
+            {
+                "type": "subagent_tool_call",
+                "subagent": subagent,
+                "name": name,
+                "args": args,
+                "id": tool_id,
+            },
+        )
 
     @staticmethod
     def subagent_tool_result(
         subagent: str, name: str, content: str, success: bool = True
     ) -> StreamEvent:
         """Tool result from inside a sub-agent."""
-        return StreamEvent("subagent_tool_result", {
-            "type": "subagent_tool_result",
-            "subagent": subagent,
-            "name": name,
-            "content": content,
-            "success": success,
-        })
+        return StreamEvent(
+            "subagent_tool_result",
+            {
+                "type": "subagent_tool_result",
+                "subagent": subagent,
+                "name": name,
+                "content": content,
+                "success": success,
+            },
+        )
 
     @staticmethod
     def subagent_end(name: str) -> StreamEvent:
@@ -86,45 +104,62 @@ class StreamEventEmitter:
     @staticmethod
     def done(response: str = "") -> StreamEvent:
         """Done event."""
-        return StreamEvent("done", {"type": "done", "content": response, "response": response})
+        return StreamEvent(
+            "done", {"type": "done", "content": response, "response": response}
+        )
 
     @staticmethod
     def usage_stats(input_tokens: int, output_tokens: int) -> StreamEvent:
         """Token usage statistics event."""
-        return StreamEvent("usage_stats", {
-            "type": "usage_stats",
-            "input_tokens": input_tokens,
-            "output_tokens": output_tokens,
-        })
+        return StreamEvent(
+            "usage_stats",
+            {
+                "type": "usage_stats",
+                "input_tokens": input_tokens,
+                "output_tokens": output_tokens,
+            },
+        )
 
     @staticmethod
     def interrupt(
-        interrupt_id: str, action_requests: list, review_configs: list | None = None,
+        interrupt_id: str,
+        action_requests: list,
+        review_configs: list | None = None,
     ) -> StreamEvent:
         """Human-in-the-loop interrupt event."""
-        return StreamEvent("interrupt", {
-            "type": "interrupt",
-            "interrupt_id": interrupt_id,
-            "action_requests": action_requests,
-            "review_configs": review_configs or [],
-        })
+        return StreamEvent(
+            "interrupt",
+            {
+                "type": "interrupt",
+                "interrupt_id": interrupt_id,
+                "action_requests": action_requests,
+                "review_configs": review_configs or [],
+            },
+        )
 
     @staticmethod
     def ask_user_interrupt(
-        interrupt_id: str, questions: list, tool_call_id: str = "",
+        interrupt_id: str,
+        questions: list,
+        tool_call_id: str = "",
     ) -> StreamEvent:
         """Agent-initiated ask_user interrupt event."""
-        return StreamEvent("ask_user", {
-            "type": "ask_user",
-            "interrupt_id": interrupt_id,
-            "questions": questions,
-            "tool_call_id": tool_call_id,
-        })
+        return StreamEvent(
+            "ask_user",
+            {
+                "type": "ask_user",
+                "interrupt_id": interrupt_id,
+                "questions": questions,
+                "tool_call_id": tool_call_id,
+            },
+        )
 
     @staticmethod
     def summarization(content: str) -> StreamEvent:
         """Context summarization event."""
-        return StreamEvent("summarization", {"type": "summarization", "content": content})
+        return StreamEvent(
+            "summarization", {"type": "summarization", "content": content}
+        )
 
     @staticmethod
     def error(message: str) -> StreamEvent: