Fix program exit when `n` is passed (#6819)

* fix program exit when `n` is passed

fix #6818

* [autofix.ci] apply automated fixes

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

CHANGELOG.md

@@ -9,6 +9,8 @@
 
 * Release tags are now prefixed with `v` again to follow SemVer convention.
   ([#6810](https://github.com/mitmproxy/mitmproxy/pull/6810), @mhils)
+* Fix a bug where mitmproxy would not exit when `-n` is passed.
+  ([#6819](https://github.com/mitmproxy/mitmproxy/pull/6819), @mhils)
 
 
 ## 17 April 2024: mitmproxy 10.3.0

mitmproxy/addons/readfile.py

@@ -71,8 +71,6 @@ class ReadFile:
             await self.load_flows_from_path(rfile)
         except exceptions.FlowReadException as e:
             logger.exception(f"Failed to read {ctx.options.rfile}: {e}")
-        finally:
-            self._read_task = None
 
     def running(self):
         if ctx.options.rfile:
@@ -80,7 +78,7 @@ class ReadFile:
 
     @command.command("readfile.reading")
     def reading(self) -> bool:
-        return bool(self._read_task)
+        return bool(self._read_task and not self._read_task.done())
 
 
 class ReadFileStdin(ReadFile):

test/mitmproxy/addons/test_readfile.py

@@ -54,13 +54,21 @@ class TestReadFile:
 
             tf = tmpdir.join("tfile")
 
-            with mock.patch("mitmproxy.master.Master.load_flow") as mck:
-                tf.write(data.getvalue())
-                tctx.configure(rf, rfile=str(tf), readfile_filter=".*")
-                mck.assert_not_awaited()
-                rf.running()
+            load_called = asyncio.Event()
+
+            async def load_flow(*_, **__):
+                load_called.set()
+
+            tctx.master.load_flow = load_flow
+
+            tf.write(data.getvalue())
+            tctx.configure(rf, rfile=str(tf), readfile_filter=".*")
+            assert not load_called.is_set()
+            rf.running()
+            await load_called.wait()
+
+            while rf.reading():
                 await asyncio.sleep(0)
-                mck.assert_awaited()
 
             tf.write(corrupt_data.getvalue())
             tctx.configure(rf, rfile=str(tf))