fix: various dropdown problems (#38020)

1. remove legacy onResponseKeepSelectedItem, refactor the code to
dropdown.js
2. make dropdown correctly handle "single selection + remote query + filter"
    * fix #38018
3. fix incorrect "transition" class usage for the dropdown dividers

web_src/css/modules/dropdown.css

@@ -80,6 +80,10 @@
   border-top-width: 0;
 }
 
+.ui.dropdown .menu .hidden { /* for hidden items and dividers */
+  display: none;
+}
+
 .ui.dropdown .menu > .header {
   margin: 1rem 0 0.75rem;
   padding: 0 1.14285714rem;

web_src/fomantic/build/components/dropdown.js

@@ -308,12 +308,12 @@ $.fn.dropdown = function(parameters) {
           firstUnfiltered: function() {
             module.verbose('Selecting first non-filtered element');
             module.remove.selectedItem();
-            $item
+            const $selectable = $item
               .not(selector.unselectable)
-              .not(selector.addition + selector.hidden)
+              .not(selector.addition + selector.hidden);
-                .eq(0)
+            let $selectedItem = $selectable.filter(`[data-value="${CSS.escape($input.val())}"]`); // GITEA-PATCH: try to re-select the last selected item for single selection
-                .addClass(className.selected)
+            if (!$selectedItem.length) $selectedItem = $item.eq(0);
-            ;
+            $selectedItem.addClass(className.selected);
           },
           nextAvailable: function($selected) {
             $selected = $selected.eq(0);
@@ -772,11 +772,13 @@ $.fn.dropdown = function(parameters) {
                 if(!Array.isArray(preSelected)) {
                     preSelected = preSelected && preSelected!=="" ? preSelected.split(settings.delimiter) : [];
                 }
-                $.each(preSelected,function(index,value){
+                if (module.is.multiple()) { // GITEA-PATCH: only hide selected items when the dropdown is "multiple selection"
-                  $item.filter('[data-value="'+CSS.escape(value)+'"]') // GITEA-PATCH: use "CSS.escape" for query selector
+                  $.each(preSelected, function (index, value) {
+                    $item.filter('[data-value="' + CSS.escape(value) + '"]') // GITEA-PATCH: use "CSS.escape" for query selector
                       .addClass(className.filtered)
-                  ;
+                    ;
-                });
+                  });
+                }
                 afterFiltered();
               });
             }

web_src/js/features/repo-new.ts

@@ -47,7 +47,6 @@ function initRepoNewTemplateSearch(form: HTMLFormElement) {
               value: String(tmplRepo.repository.id),
             });
           }
-          $repoTemplateDropdown.fomanticExt.onResponseKeepSelectedItem($repoTemplateDropdown, inputRepoTemplate.value);
           return {results};
         },
         cache: false,

web_src/js/modules/fomantic/dropdown.test.ts

@@ -13,13 +13,13 @@ test('hideScopedEmptyDividers-simple', () => {
 </div>`);
   hideScopedEmptyDividers(container);
   expect(container.innerHTML).toEqual(`
-<div class="divider hidden transition"></div>
+<div class="divider hidden"></div>
 <div class="item">a</div>
-<div class="divider hidden transition"></div>
+<div class="divider hidden"></div>
-<div class="divider hidden transition"></div>
+<div class="divider hidden"></div>
 <div class="divider"></div>
 <div class="item">b</div>
-<div class="divider hidden transition"></div>
+<div class="divider hidden"></div>
 `);
 });
 
@@ -35,7 +35,7 @@ test('hideScopedEmptyDividers-items-all-filtered', () => {
   hideScopedEmptyDividers(container);
   expect(container.innerHTML).toEqual(`
 <div class="any"></div>
-<div class="divider hidden transition"></div>
+<div class="divider hidden"></div>
 <div class="item filtered">a</div>
 <div class="item filtered">b</div>
 <div class="divider"></div>
@@ -52,7 +52,7 @@ test('hideScopedEmptyDividers-hide-last', () => {
   hideScopedEmptyDividers(container);
   expect(container.innerHTML).toEqual(`
 <div class="item">a</div>
-<div class="divider hidden transition" data-scope="b"></div>
+<div class="divider hidden" data-scope="b"></div>
 <div class="item tw-hidden" data-scope="b">b</div>
 `);
 });
@@ -68,9 +68,9 @@ test('hideScopedEmptyDividers-scoped-items', () => {
   hideScopedEmptyDividers(container);
   expect(container.innerHTML).toEqual(`
 <div class="item" data-scope="">a</div>
-<div class="divider hidden transition" data-scope="b"></div>
+<div class="divider hidden" data-scope="b"></div>
 <div class="item tw-hidden" data-scope="b">b</div>
-<div class="divider hidden transition" data-scope=""></div>
+<div class="divider hidden" data-scope=""></div>
 <div class="item" data-scope="">c</div>
 `);
 });

web_src/js/modules/fomantic/dropdown.ts

@@ -8,7 +8,6 @@ const fomanticDropdownFn = $.fn.dropdown;
 export function initAriaDropdownPatch() {
   if ($.fn.dropdown === ariaDropdownFn) throw new Error('initAriaDropdownPatch could only be called once');
   $.fn.dropdown = ariaDropdownFn;
-  $.fn.fomanticExt.onResponseKeepSelectedItem = onResponseKeepSelectedItem;
   $.fn.fomanticExt.onDropdownAfterFiltered = onDropdownAfterFiltered;
   (ariaDropdownFn as FomanticInitFunction).settings = fomanticDropdownFn.settings;
 }
@@ -296,8 +295,8 @@ export function hideScopedEmptyDividers(container: Element) {
   let curScope: string = '', lastVisibleScope: string = '';
   const isDivider = (item: Element) => item.classList.contains('divider');
   const isScopedDivider = (item: Element) => isDivider(item) && item.hasAttribute('data-scope');
-  const hideDivider = (item: Element) => item.classList.add('hidden', 'transition'); // dropdown has its own classes to hide items
+  const hideDivider = (item: Element) => item.classList.add('hidden'); // dropdown has its own classes to hide items
-  const showDivider = (item: Element) => item.classList.remove('hidden', 'transition');
+  const showDivider = (item: Element) => item.classList.remove('hidden');
   const isHidden = (item: Element) => item.classList.contains('hidden') || item.classList.contains('filtered') || item.classList.contains('tw-hidden');
   const handleScopeSwitch = (itemScope: string) => {
     if (curScopeVisibleItems.length === 1 && isScopedDivider(curScopeVisibleItems[0])) {
@@ -347,19 +346,3 @@ export function hideScopedEmptyDividers(container: Element) {
     if (visibleItems[i + 1].matches('.divider')) hideDivider(visibleItems[i]);
   }
 }
-
-function onResponseKeepSelectedItem(dropdown: typeof $ | HTMLElement, selectedValue: string) {
-  // There is a bug in fomantic dropdown when using "apiSettings" to fetch data
-  // * when there is a selected item, the dropdown insists on hiding the selected one from the list:
-  // * in the "filter" function: ('[data-value="'+value+'"]').addClass(className.filtered)
-  //
-  // When user selects one item, and click the dropdown again,
-  // then the dropdown only shows other items and will select another (wrong) one.
-  // It can't be easily fix by using setTimeout(patch, 0) in `onResponse` because the `onResponse` is called before another `setTimeout(..., timeLeft)`
-  // Fortunately, the "timeLeft" is controlled by "loadingDuration" which is always zero at the moment, so we can use `setTimeout(..., 10)`
-  const elDropdown = (dropdown instanceof HTMLElement) ? dropdown : (dropdown as any)[0];
-  setTimeout(() => {
-    queryElems(elDropdown, `.menu .item[data-value="${CSS.escape(selectedValue)}"].filtered`, (el) => el.classList.remove('filtered'));
-    $(elDropdown).dropdown('set selected', selectedValue ?? '');
-  }, 10);
-}