[SelectPanel] Include value in activation events (#3009)

Author: camertron

.changeset/chatty-jokes-walk.md

@@ -0,0 +1,5 @@
+---
+'@primer/view-components': minor
+---
+
+Include value in event metadata when SelectPanel items are activated

app/components/primer/alpha/select_panel_element.ts

@@ -867,8 +867,12 @@ export class SelectPanelElement extends HTMLElement {
     const activationSuccess = this.dispatchEvent(
       new CustomEvent('beforeItemActivated', {
         bubbles: true,
-        detail: {item, checked},
         cancelable: true,
+        detail: {
+          item,
+          checked,
+          value: this.#getItemContent(item)?.getAttribute('data-value'),
+        },
       }),
     )
 
@@ -909,7 +913,11 @@ export class SelectPanelElement extends HTMLElement {
     this.dispatchEvent(
       new CustomEvent('itemActivated', {
         bubbles: true,
-        detail: {item, checked},
+        detail: {
+          item,
+          checked,
+          value: this.#getItemContent(item)?.getAttribute('data-value'),
+        },
       }),
     )
   }

app/components/primer/shared_events.ts

@@ -1,10 +1,12 @@
 export type ItemActivatedEvent = {
   item: Element
   checked: boolean
+  value: string | null
 }
 
 declare global {
   interface HTMLElementEventMap {
     itemActivated: CustomEvent<ItemActivatedEvent>
+    beforeItemActivated: CustomEvent<ItemActivatedEvent>
   }
 }

test/system/alpha/select_panel_test.rb

@@ -718,16 +718,41 @@ def test_uncheck_item_via_js_api
       refute_selector "li[data-item-id=item1] [aria-selected=true]"
     end
 
+    def test_fires_event_before_activation
+      visit_preview(:single_select)
+
+      evaluate_multiline_script(<<~JS)
+        window.activatedItemText = null
+        window.activatedItemChecked = false
+        window.activatedItemValue = null
+
+        document.querySelector('select-panel').addEventListener('beforeItemActivated', (event) => {
+          window.activatedItemText = event.detail.item.innerText
+          window.activatedItemChecked = event.detail.checked
+          window.activatedItemValue = event.detail.value
+        })
+      JS
+
+      click_on_invoker_button
+      click_on_first_item
+
+      assert page.evaluate_script("window.activatedItemChecked")
+      assert_equal "Item 1", page.evaluate_script("window.activatedItemText")
+      assert_equal "1", page.evaluate_script("window.activatedItemValue")
+    end
+
     def test_fires_event_on_activation
       visit_preview(:single_select)
 
       evaluate_multiline_script(<<~JS)
         window.activatedItemText = null
         window.activatedItemChecked = false
+        window.activatedItemValue = null
 
         document.querySelector('select-panel').addEventListener('itemActivated', (event) => {
           window.activatedItemText = event.detail.item.innerText
           window.activatedItemChecked = event.detail.checked
+          window.activatedItemValue = event.detail.value
         })
       JS
 
@@ -736,6 +761,7 @@ def test_fires_event_on_activation
 
       assert page.evaluate_script("window.activatedItemChecked")
       assert_equal "Item 1", page.evaluate_script("window.activatedItemText")
+      assert_equal "1", page.evaluate_script("window.activatedItemValue")
     end
 
     def test_cancelling_before_item_activated_event_prevents_selection