Improve selectize input selection logic

Refactors the selection logic to only remove items not in the desired set and only add missing items, improving efficiency and correctness when updating selected values in InputSelectize.

Author: karangattu

shiny/playwright/controller/_input_controls.py

@@ -1198,16 +1198,32 @@ def set(
             selected = [selected]
         self._loc_events.click()
 
-        while True:
-            remove_button = self._loc_events.locator("> .item > .remove").first
-            if remove_button.count() == 0:
-                break
-            remove_button.click()
+        currently_selected: list[str] = []
+        selected_items = self._loc_events.locator("> .item")
+        for i in range(selected_items.count()):
+            item = selected_items.nth(i)
+            data_value = item.get_attribute("data-value")
+            if data_value:
+                currently_selected.append(data_value)
+
+        current_set = set(currently_selected)
+        desired_set = set(selected)
+
+        for current_value in currently_selected:
+            if current_value not in desired_set:
+                item_to_remove = self._loc_events.locator(
+                    f"> .item[data-value='{current_value}']"
+                )
+                if item_to_remove.count() > 0:
+                    item_to_remove.click()
+                    self.page.keyboard.press("Delete")
 
         for value in selected:
-            self._loc_selectize.locator(f"[data-value='{value}']").click(
-                timeout=timeout
-            )
+            if value not in current_set:
+                self._loc_selectize.locator(f"[data-value='{value}']").click(
+                    timeout=timeout
+                )
+
         self._loc_events.press("Escape")
 
     def expect_choices(