Move dropdown offset function logic into private function. (#28138)

diff --git a/js/src/dropdown.js b/js/src/dropdown.js
index 9aaf5a339ea29dc59c53e33900f75cb73d43beaa..31deaa725ee2bdebc13c2daedfdf0e23f20443a1 100644 (file)
--- a/js/src/dropdown.js
+++ b/js/src/dropdown.js
@@ -319,24 +319,30 @@ class Dropdown {
     return $(this._element).closest('.navbar').length > 0
   }
 
-  _getPopperConfig() {
-    const offsetConf = {}
+  _getOffset() {
+    const offset = {}
+
     if (typeof this._config.offset === 'function') {
-      offsetConf.fn = (data) => {
+      offset.fn = (data) => {
         data.offsets = {
           ...data.offsets,
-          ...this._config.offset(data.offsets) || {}
+          ...this._config.offset(data.offsets, this._element) || {}
         }
+
         return data
       }
     } else {
-      offsetConf.offset = this._config.offset
+      offset.offset = this._config.offset
     }
 
+    return offset
+  }
+
+  _getPopperConfig() {
     const popperConfig = {
       placement: this._getPlacement(),
       modifiers: {
-        offset: offsetConf,
+        offset: this._getOffset(),
         flip: {
           enabled: this._config.flip
         },
@@ -352,6 +358,7 @@ class Dropdown {
         enabled: false
       }
     }
+
     return popperConfig
   }
 

diff --git a/js/tests/unit/dropdown.js b/js/tests/unit/dropdown.js
index fd9b7f9629588c8286d411debd186c158c8c2f7b..1ecfd1f8bf8f35806ed16060e0b9486c45dfcc00 100644 (file)
--- a/js/tests/unit/dropdown.js
+++ b/js/tests/unit/dropdown.js
@@ -1361,4 +1361,59 @@ $(function () {
     $dropdown.hide()
     assert.ok($dropdown.parent('.dropdown').hasClass('show'))
   })
+
+  QUnit.test('should create offset modifier correctly when offset option is a function', function (assert) {
+    assert.expect(2)
+
+    var getOffset = function (offsets) {
+      return offsets
+    }
+
+    var dropdownHTML =
+      '<div class="dropdown">' +
+      '  <a href="#" class="dropdown-toggle" data-toggle="dropdown">Dropdown</a>' +
+      '  <div class="dropdown-menu">' +
+      '    <a class="dropdown-item" href="#">Another link</a>' +
+      '  </div>' +
+      '</div>'
+
+    var $dropdown = $(dropdownHTML)
+      .appendTo('#qunit-fixture')
+      .find('[data-toggle="dropdown"]')
+      .bootstrapDropdown({
+        offset: getOffset
+      })
+
+    var dropdown = $dropdown.data('bs.dropdown')
+    var offset = dropdown._getOffset()
+
+    assert.ok(typeof offset.offset === 'undefined')
+    assert.ok(typeof offset.fn === 'function')
+  })
+
+  QUnit.test('should create offset modifier correctly when offset option is not a function', function (assert) {
+    assert.expect(2)
+
+    var dropdownHTML =
+      '<div class="dropdown">' +
+      '  <a href="#" class="dropdown-toggle" data-toggle="dropdown">Dropdown</a>' +
+      '  <div class="dropdown-menu">' +
+      '    <a class="dropdown-item" href="#">Another link</a>' +
+      '  </div>' +
+      '</div>'
+
+    var myOffset = 42
+    var $dropdown = $(dropdownHTML)
+      .appendTo('#qunit-fixture')
+      .find('[data-toggle="dropdown"]')
+      .bootstrapDropdown({
+        offset: myOffset
+      })
+
+    var dropdown = $dropdown.data('bs.dropdown')
+    var offset = dropdown._getOffset()
+
+    assert.strictEqual(offset.offset, myOffset)
+    assert.ok(typeof offset.fn === 'undefined')
+  })
 })

diff --git a/site/docs/4.2/components/dropdowns.md b/site/docs/4.2/components/dropdowns.md
index 6011bd98960781580b877e3cc74add42c46fa8ee..2b5ee2014ea92e6295daa9d691ad724b185da4fd 100644 (file)
--- a/site/docs/4.2/components/dropdowns.md
+++ b/site/docs/4.2/components/dropdowns.md
@@ -845,7 +845,11 @@ Options can be passed via data attributes or JavaScript. For data attributes, ap
       <td>offset</td>
       <td>number | string | function</td>
       <td>0</td>
-      <td>Offset of the dropdown relative to its target. For more information refer to Popper.js's <a href="https://popper.js.org/popper-documentation.html#modifiers..offset.offset">offset docs</a>.</td>
+      <td>
+        <p>Offset of the dropdown relative to its target.</p>
+        <p>When a function is used to determine the offset, it is called with an object containing the offset data as its first argument. The function must return an object with the same structure. The triggering element DOM node is passed as the second argument.</p>
+        <p>For more information refer to Popper.js's <a href="https://popper.js.org/popper-documentation.html#modifiers..offset.offset">offset docs</a>.</p>
+      </td>
     </tr>
     <tr>
       <td>flip</td>