use default parameters (#698)

* use default parameters

* Fix argument name in README

README.md

@@ -809,7 +809,7 @@ const values = example.getValue(true); // returns ['value 1', 'value 2'];
 const valueArray = example.getValue(); // returns [{ active: true, choiceId: 1, highlighted: false, id: 1, label: 'Label 1', value: 'Value 1'},  { active: true, choiceId: 2, highlighted: false, id: 2, label: 'Label 2', value: 'Value 2'}];
 ```
 
-### setValue(args);
+### setValue(items);
 **Input types affected:** `text`
 
 **Usage:** Set value of input based on an array of objects or strings. This behaves exactly the same as passing items via the `items` option but can be called after initialising Choices.

src/scripts/choices.js

@@ -390,12 +390,15 @@ class Choices {
     return this._isSelectOneElement ? values[0] : values;
   }
 
-  setValue(args) {
+  /**
+   * @param {string[] | import('../../types/index').Choices.Item[]} items
+   */
+  setValue(items) {
     if (!this.initialised) {
       return this;
     }
 
-    [...args].forEach(value => this._setChoiceOrItem(value));
+    items.forEach(value => this._setChoiceOrItem(value));
     return this;
   }
 
@@ -608,8 +611,11 @@ class Choices {
     }
   }
 
-  _createGroupsFragment(groups, choices, fragment) {
+  _createGroupsFragment(
-    const groupFragment = fragment || document.createDocumentFragment();
+    groups,
+    choices,
+    fragment = document.createDocumentFragment(),
+  ) {
     const getGroupChoices = group =>
       choices.filter(choice => {
         if (this._isSelectOneElement) {
@@ -630,17 +636,20 @@ class Choices {
       const groupChoices = getGroupChoices(group);
       if (groupChoices.length >= 1) {
         const dropdownGroup = this._getTemplate('choiceGroup', group);
-        groupFragment.appendChild(dropdownGroup);
+        fragment.appendChild(dropdownGroup);
-        this._createChoicesFragment(groupChoices, groupFragment, true);
+        this._createChoicesFragment(groupChoices, fragment, true);
       }
     });
 
-    return groupFragment;
+    return fragment;
   }
 
-  _createChoicesFragment(choices, fragment, withinGroup = false) {
+  _createChoicesFragment(
+    choices,
+    fragment = document.createDocumentFragment(),
+    withinGroup = false,
+  ) {
     // Create a fragment to store our list items (so we don't have to update the DOM for each item)
-    const choicesFragment = fragment || document.createDocumentFragment();
     const {
       renderSelectedChoices,
       searchResultLimit,
@@ -658,7 +667,7 @@ class Choices {
           choice,
           this.config.itemSelectText,
         );
-        choicesFragment.appendChild(dropdownItem);
+        fragment.appendChild(dropdownItem);
       }
     };
 
@@ -704,13 +713,12 @@ class Choices {
       }
     }
 
-    return choicesFragment;
+    return fragment;
   }
 
-  _createItemsFragment(items, fragment = null) {
+  _createItemsFragment(items, fragment = document.createDocumentFragment()) {
     // Create fragment to add elements to
     const { shouldSortItems, sortFn, removeItemButton } = this.config;
-    const itemListFragment = fragment || document.createDocumentFragment();
 
     // If sorting is enabled, filter items
     if (shouldSortItems && !this._isSelectOneElement) {
@@ -729,13 +737,13 @@ class Choices {
       // Create new list element
       const listItem = this._getTemplate('item', item, removeItemButton);
       // Append it to list
-      itemListFragment.appendChild(listItem);
+      fragment.appendChild(listItem);
     };
 
     // Add each list item to list
     items.forEach(item => addItemToFragment(item));
 
-    return itemListFragment;
+    return fragment;
   }
 
   _triggerChange(value) {