GH-132439: Fix REPL swallowing characters entered with AltGr on cmd.exe

Lib/_pyrepl/windows_console.py

@@ -464,7 +464,7 @@ def get_event(self, block: bool = True) -> Event | None:
 
  if key == "\r":
  # Make enter unix-like
- return Event(evt="key", data="\n", raw=b"\n")
+ return Event(evt="key", data="\n")
  elif key_event.wVirtualKeyCode == 8:
  # Turn backspace directly into the command
  key = "backspace"
@@ -476,9 +476,9 @@ def get_event(self, block: bool = True) -> Event | None:
  key = f"ctrl{key}"
  elif key_event.dwControlKeyState & ALT_ACTIVE:
  # queue the key, return the meta command
- self.event_queue.insert(Event(evt="key", data=key, raw=key))
+ self.event_queue.insert(Event(evt="key", data=key))
  return Event(evt="key", data="\033") # keymap.py uses this for meta
- return Event(evt="key", data=key, raw=key)
+ return Event(evt="key", data=key)
  if block:
  continue
 
@@ -489,11 +489,15 @@ def get_event(self, block: bool = True) -> Event | None:
  continue
 
  if key_event.dwControlKeyState & ALT_ACTIVE:
- # queue the key, return the meta command
- self.event_queue.insert(Event(evt="key", data=key, raw=raw_key))
- return Event(evt="key", data="\033") # keymap.py uses this for meta
-
- return Event(evt="key", data=key, raw=raw_key)
+ # Do not swallow characters that have been entered via AltGr:
+ # Windows internally converts AltGr to CTRL+ALT, see
+ # https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-vkkeyscanw
+ if not key_event.dwControlKeyState & CTRL_ACTIVE:
+ # queue the key, return the meta command
+ self.event_queue.insert(Event(evt="key", data=key))
+ return Event(evt="key", data="\033") # keymap.py uses this for meta
+
+ return Event(evt="key", data=key)
  return self.event_queue.get()
 
  def push_char(self, char: int | bytes) -> None:

Lib/test/test_pyrepl/test_windows_console.py

@@ -24,6 +24,7 @@
  MOVE_DOWN,
  ERASE_IN_LINE,
  )
+ import _pyrepl.windows_console as wc
 except ImportError:
  pass
 
@@ -350,8 +351,226 @@ def test_multiline_ctrl_z(self):
  Event(evt="key", data='\x1a', raw=bytearray(b'\x1a')),
  ],
  )
- reader, _ = self.handle_events_narrow(events)
+ reader, con = self.handle_events_narrow(events)
  self.assertEqual(reader.cxy, (2, 3))
+ con.restore()
+
+
+class WindowsConsoleGetEventTests(TestCase):
+ # Virtual-Key Codes: https://learn.microsoft.com/en-us/windows/win32/inputdev/virtual-key-codes
+ VK_BACK = 0x08
+ VK_RETURN = 0x0D
+ VK_LEFT = 0x25
+ VK_7 = 0x37
+ VK_M = 0x4D
+ # Used for miscellaneous characters; it can vary by keyboard.
+ # For the US standard keyboard, the '" key.
+ # For the German keyboard, the Ä key.
+ VK_OEM_7 = 0xDE
+
+ # State of control keys: https://learn.microsoft.com/en-us/windows/console/key-event-record-str
+ RIGHT_ALT_PRESSED = 0x0001
+ RIGHT_CTRL_PRESSED = 0x0004
+ LEFT_ALT_PRESSED = 0x0002
+ LEFT_CTRL_PRESSED = 0x0008
+ ENHANCED_KEY = 0x0100
+ SHIFT_PRESSED = 0x0010
+
+
+ def get_event(self, input_records, **kwargs) -> Console:
+ self.console = WindowsConsole(encoding='utf-8')
+ self.mock = MagicMock(side_effect=input_records)
+ self.console._read_input = self.mock
+ self.console._WindowsConsole__vt_support = kwargs.get("vt_support",
+ False)
+ event = self.console.get_event(block=False)
+ return event
+
+ def get_input_record(self, unicode_char, vcode=0, control=0):
+ return wc.INPUT_RECORD(
+ wc.KEY_EVENT,
+ wc.ConsoleEvent(KeyEvent=
+ wc.KeyEvent(
+ bKeyDown=True,
+ wRepeatCount=1,
+ wVirtualKeyCode=vcode,
+ wVirtualScanCode=0, # not used
+ uChar=wc.Char(unicode_char),
+ dwControlKeyState=control
+ )))
+
+ def test_EmptyBuffer(self):
+ self.assertEqual(self.get_event([None]), None)
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_WINDOW_BUFFER_SIZE_EVENT(self):
+ ir = wc.INPUT_RECORD(
+ wc.WINDOW_BUFFER_SIZE_EVENT,
+ wc.ConsoleEvent(WindowsBufferSizeEvent=
+ wc.WindowsBufferSizeEvent(
+ wc._COORD(0, 0))))
+ self.assertEqual(self.get_event([ir]), Event("resize", ""))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_KEY_EVENT_up_ignored(self):
+ ir = wc.INPUT_RECORD(
+ wc.KEY_EVENT,
+ wc.ConsoleEvent(KeyEvent=
+ wc.KeyEvent(bKeyDown=False)))
+ self.assertEqual(self.get_event([ir]), None)
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_unhandled_events(self):
+ for event in (wc.FOCUS_EVENT, wc.MENU_EVENT, wc.MOUSE_EVENT):
+ ir = wc.INPUT_RECORD(
+ event,
+ # fake data, nothing is read except bKeyDown
+ wc.ConsoleEvent(KeyEvent=
+ wc.KeyEvent(bKeyDown=False)))
+ self.assertEqual(self.get_event([ir]), None)
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_enter(self):
+ ir = self.get_input_record("\r", self.VK_RETURN)
+ self.assertEqual(self.get_event([ir]), Event("key", "\n"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_backspace(self):
+ ir = self.get_input_record("\x08", self.VK_BACK)
+ self.assertEqual(
+ self.get_event([ir]), Event("key", "backspace"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_m(self):
+ ir = self.get_input_record("m", self.VK_M)
+ self.assertEqual(self.get_event([ir]), Event("key", "m"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_M(self):
+ ir = self.get_input_record("M", self.VK_M, self.SHIFT_PRESSED)
+ self.assertEqual(self.get_event([ir]), Event("key", "M"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_left(self):
+ # VK_LEFT is sent as ENHANCED_KEY
+ ir = self.get_input_record("\x00", self.VK_LEFT, self.ENHANCED_KEY)
+ self.assertEqual(self.get_event([ir]), Event("key", "left"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_left_RIGHT_CTRL_PRESSED(self):
+ ir = self.get_input_record(
+ "\x00", self.VK_LEFT, self.RIGHT_CTRL_PRESSED | self.ENHANCED_KEY)
+ self.assertEqual(
+ self.get_event([ir]), Event("key", "ctrl left"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_left_LEFT_CTRL_PRESSED(self):
+ ir = self.get_input_record(
+ "\x00", self.VK_LEFT, self.LEFT_CTRL_PRESSED | self.ENHANCED_KEY)
+ self.assertEqual(
+ self.get_event([ir]), Event("key", "ctrl left"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_left_RIGHT_ALT_PRESSED(self):
+ ir = self.get_input_record(
+ "\x00", self.VK_LEFT, self.RIGHT_ALT_PRESSED | self.ENHANCED_KEY)
+ self.assertEqual(self.get_event([ir]), Event(evt="key", data="\033"))
+ self.assertEqual(
+ self.console.get_event(), Event("key", "left"))
+ # self.mock is not called again, since the second time we read from the
+ # command queue
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_left_LEFT_ALT_PRESSED(self):
+ ir = self.get_input_record(
+ "\x00", self.VK_LEFT, self.LEFT_ALT_PRESSED | self.ENHANCED_KEY)
+ self.assertEqual(self.get_event([ir]), Event(evt="key", data="\033"))
+ self.assertEqual(
+ self.console.get_event(), Event("key", "left"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_m_LEFT_ALT_PRESSED_and_LEFT_CTRL_PRESSED(self):
+ # For the shift keys, Windows does not send anything when
+ # ALT and CTRL are both pressed, so let's test with VK_M.
+ # get_event() receives this input, but does not
+ # generate an event.
+ # This is for e.g. an English keyboard layout, for a
+ # German layout this returns `µ`, see test_AltGr_m.
+ ir = self.get_input_record(
+ "\x00", self.VK_M, self.LEFT_ALT_PRESSED | self.LEFT_CTRL_PRESSED)
+ self.assertEqual(self.get_event([ir]), None)
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_m_LEFT_ALT_PRESSED(self):
+ ir = self.get_input_record(
+ "m", vcode=self.VK_M, control=self.LEFT_ALT_PRESSED)
+ self.assertEqual(self.get_event([ir]), Event(evt="key", data="\033"))
+ self.assertEqual(self.console.get_event(), Event("key", "m"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_m_RIGHT_ALT_PRESSED(self):
+ ir = self.get_input_record(
+ "m", vcode=self.VK_M, control=self.RIGHT_ALT_PRESSED)
+ self.assertEqual(self.get_event([ir]), Event(evt="key", data="\033"))
+ self.assertEqual(self.console.get_event(), Event("key", "m"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_AltGr_7(self):
+ # E.g. on a German keyboard layout, '{' is entered via
+ # AltGr + 7, where AltGr is the right Alt key on the keyboard.
+ # In this case, Windows automatically sets
+ # RIGHT_ALT_PRESSED = 0x0001 + LEFT_CTRL_PRESSED = 0x0008
+ # This can also be entered like
+ # LeftAlt + LeftCtrl + 7 or
+ # LeftAlt + RightCtrl + 7
+ # See https://learn.microsoft.com/en-us/windows/console/key-event-record-str
+ # https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-vkkeyscanw
+ ir = self.get_input_record(
+ "{", vcode=self.VK_7,
+ control=self.RIGHT_ALT_PRESSED | self.LEFT_CTRL_PRESSED)
+ self.assertEqual(self.get_event([ir]), Event("key", "{"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_AltGr_m(self):
+ # E.g. on a German keyboard layout, this yields 'µ'
+ # Let's use LEFT_ALT_PRESSED and RIGHT_CTRL_PRESSED this
+ # time, to cover that, too. See above in test_AltGr_7.
+ ir = self.get_input_record(
+ "µ", vcode=self.VK_M, control=self.LEFT_ALT_PRESSED | self.RIGHT_CTRL_PRESSED)
+ self.assertEqual(self.get_event([ir]), Event("key", "µ"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_umlaut_a_german(self):
+ ir = self.get_input_record("ä", self.VK_OEM_7)
+ self.assertEqual(self.get_event([ir]), Event("key", "ä"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ # virtual terminal tests
+ # Note: wVirtualKeyCode, wVirtualScanCode and dwControlKeyState
+ # are always zero in this case.
+ # "\r" and backspace are handled specially, everything else
+ # is handled in "elif self.__vt_support:" in WindowsConsole.get_event().
+ # Hence, only one regular key ("m") and a terminal sequence
+ # are sufficient to test here, the real tests happen in test_eventqueue
+ # and test_keymap.
+
+ def test_enter_vt(self):
+ ir = self.get_input_record("\r")
+ self.assertEqual(self.get_event([ir], vt_support=True),
+ Event("key", "\n"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_backspace_vt(self):
+ ir = self.get_input_record("\x7f")
+ self.assertEqual(self.get_event([ir], vt_support=True),
+ Event("key", "backspace", b"\x7f"))
+ self.assertEqual(self.mock.call_count, 1)
+
+ def test_up_vt(self):
+ irs = [self.get_input_record(x) for x in "\x1b[A"]
+ self.assertEqual(self.get_event(irs, vt_support=True),
+ Event(evt='key', data='up', raw=bytearray(b'\x1b[A')))
+ self.assertEqual(self.mock.call_count, 3)
 
 
 if __name__ == "__main__":

Misc/NEWS.d/next/Library/2025-04-12-16-29-42.gh-issue-132439.3twrU6.rst

@@ -0,0 +1,2 @@
+Fix ``PyREPL`` on Windows: characters entered via AltGr are swallowed.
+Patch by Chris Eibl.