Add extra unit tests for password field movement

Here we're just testing the exceptional situations.

tests/input/test_input_key_movement_actions.py

@@ -97,6 +97,16 @@ async def test_input_left_word_from_end() -> None:
             assert input.cursor_position == expected_at[input.id]
 
 
+async def test_password_input_left_word_from_end() -> None:
+    """Going left one word from the end in a password field should land at home."""
+    async with InputTester().run_test() as pilot:
+        for input in pilot.app.query(Input):
+            input.action_end()
+            input.password = True
+            input.action_cursor_left_word()
+            assert input.cursor_position == 0
+
+
 async def test_input_right_word_from_home() -> None:
     """Going right one word from the start should land correctly.."""
     async with InputTester().run_test() as pilot:
@@ -112,6 +122,15 @@ async def test_input_right_word_from_home() -> None:
             assert input.cursor_position == expected_at[input.id]
 
 
+async def test_password_input_right_word_from_home() -> None:
+    """Going right one word from the start of a password input should go to the end."""
+    async with InputTester().run_test() as pilot:
+        for input in pilot.app.query(Input):
+            input.password = True
+            input.action_cursor_right_word()
+            assert input.cursor_position == len(input.value)
+
+
 async def test_input_right_word_from_end() -> None:
     """Going right one word from the end should do nothing."""
     async with InputTester().run_test() as pilot: