fixes #14282 - Already Visible collapse gets closed when .collapse('show') is called

js/collapse.js

@@ -124,7 +124,7 @@
       var data    = $this.data('bs.collapse')
       var options = $.extend({}, Collapse.DEFAULTS, $this.data(), typeof option == 'object' && option)
 
-      if (!data && options.toggle && option == 'show') option = !option
+      if (!data && options.toggle && option == 'show') options.toggle = false
       if (!data) $this.data('bs.collapse', (data = new Collapse(this, options)))
       if (typeof option == 'string') data[option]()
     })

js/tests/unit/collapse.js

@@ -102,6 +102,38 @@ $(function () {
     $target.click()
   })
 
+  test('should not close a collapse when initialized with "show" if already shown', function () {
+    stop()
+
+    expect(0)
+
+    var $test = $('<div id="test1" class="in"/>')
+      .appendTo('#qunit-fixture')
+      .on('hide.bs.collapse', function () {
+        ok(false)
+      })
+
+    $test.bootstrapCollapse('show')
+
+    setTimeout(start, 0)
+  })
+
+  test('should open a collapse when initialized with "show" if not already shown', function () {
+    stop()
+
+    expect(1)
+
+    var $test = $('<div id="test1" />')
+      .appendTo('#qunit-fixture')
+      .on('show.bs.collapse', function () {
+        ok(true)
+      })
+
+    $test.bootstrapCollapse('show')
+
+    setTimeout(start, 0)
+  })
+
   test('should remove "collapsed" class from active accordion target', function () {
     stop()