simplify flush_buf() since raw is gone

no caller needs the buffer contents anymore, so just clear it
without returning

Author: HCYT

Lib/_pyrepl/base_eventqueue.py

@@ -54,13 +54,11 @@ def empty(self) -> bool:
         """
         return not self.events
 
-    def flush_buf(self) -> bytearray:
+    def flush_buf(self) -> None:
         """
-        Flushes the buffer and returns its contents.
+        Flushes the buffer.
         """
-        old = self.buf
         self.buf = bytearray()
-        return old
 
     def insert(self, event: Event) -> None:
         """
@@ -98,7 +96,9 @@ def push(self, char: int | bytes) -> None:
             trace('unrecognized escape sequence, propagating...')
             self.keymap = self.compiled_keymap
             self.insert(Event('key', '\033'))
-            for _c in self.flush_buf()[1:]:
+            remaining = self.buf[1:]
+            self.flush_buf()
+            for _c in remaining:
                 self.push(_c)
 
         else:

Lib/test/test_pyrepl/test_eventqueue.py

@@ -41,7 +41,7 @@ def test_empty(self):
     def test_flush_buf(self):
         eq = self.make_eventqueue()
         eq.buf.extend(b"test")
-        self.assertEqual(eq.flush_buf(), b"test")
+        eq.flush_buf()
         self.assertEqual(eq.buf, bytearray())
 
     def test_insert(self):