Hopefully final touches on the new tab completion.

tests/unit/test_tab_completion_manager.py

@@ -81,6 +81,43 @@ def test_unique_completion_speaks_inserted_suffix():
     assert state["lastProcessedDelta"] == "cuments/"
 
 
+@pytest.mark.unit
+def test_small_completion_speaks_inserted_suffix():
+    manager, env, _input_manager = _build_env(
+        "cd gi".ljust(20), {"x": 5, "y": 0}
+    )
+
+    manager.capture_if_tab()
+    _set_screen_update(
+        env,
+        "cd git/".ljust(20),
+        {"x": 7, "y": 0},
+        delta="t/",
+        typing=True,
+    )
+
+    assert manager.process_update() == "t/"
+
+
+@pytest.mark.unit
+def test_completion_processed_once_for_cursor_and_screen_update():
+    manager, env, _input_manager = _build_env(
+        "cd gi".ljust(20), {"x": 5, "y": 0}
+    )
+
+    manager.capture_if_tab()
+    _set_screen_update(
+        env,
+        "cd git/".ljust(20),
+        {"x": 7, "y": 0},
+        delta="t/",
+        typing=True,
+    )
+
+    assert manager.process_update() == "t/"
+    assert manager.process_update() == ""
+
+
 @pytest.mark.unit
 def test_candidate_list_speaks_visible_list_without_cursor_advance():
     old_text = "\n".join(["$ cd Do".ljust(20), "".ljust(20), "".ljust(20)])