fix: simplify more code and avoid reusing code (DRY) (#368)

* fix: simplify more code and avoid reusing code (DRY)

Author: ghiscoding

packages/multiple-select-vanilla/src/MultipleSelectInstance.ts

@@ -180,7 +180,7 @@ export class MultipleSelectInstance {
     }
 
     // single or multiple
-    if (typeof this.options.single === 'undefined') {
+    if (this.options.single === undefined) {
       this.options.single = !this.elm.multiple;
     }
 

packages/multiple-select-vanilla/src/constants.ts

@@ -5,6 +5,8 @@ import English from './locales/multiple-select-en-US.js';
 const BLOCK_ROWS = 50;
 const CLUSTER_BLOCKS = 4;
 
+const noopFalse = () => false;
+const noopTrue = () => true;
 const DEFAULTS: Partial<MultipleSelectOption> = {
   name: '',
   placeholder: '',
@@ -64,23 +66,23 @@ const DEFAULTS: Partial<MultipleSelectOption> = {
   textTemplate: (elm: HTMLOptionElement) => elm.innerHTML.trim(),
   labelTemplate: (elm: HTMLOptionElement) => elm.label,
 
-  onBeforeOpen: () => false,
-  onOpen: () => false,
-  onClose: () => false,
-  onCheckAll: () => false,
-  onUncheckAll: () => false,
-  onFocus: () => false,
-  onBlur: () => false,
-  onOptgroupClick: () => false,
-  onBeforeClick: () => true,
-  onClick: () => false,
-  onFilter: () => false,
-  onFilterClear: () => false,
-  onClear: () => false,
-  onAfterCreate: () => false,
-  onDestroy: () => false,
-  onAfterDestroy: () => false,
-  onDestroyed: () => false,
+  onBeforeOpen: noopFalse,
+  onOpen: noopFalse,
+  onClose: noopFalse,
+  onCheckAll: noopFalse,
+  onUncheckAll: noopFalse,
+  onFocus: noopFalse,
+  onBlur: noopFalse,
+  onOptgroupClick: noopFalse,
+  onBeforeClick: noopTrue,
+  onClick: noopFalse,
+  onFilter: noopFalse,
+  onFilterClear: noopFalse,
+  onClear: noopFalse,
+  onAfterCreate: noopFalse,
+  onDestroy: noopFalse,
+  onAfterDestroy: noopFalse,
+  onDestroyed: noopFalse,
 };
 
 const METHODS = [

packages/multiple-select-vanilla/src/multiple-select.ts

@@ -66,6 +66,6 @@ multipleSelect.locales = { ...English } as MultipleSelectLocales; // load Englis
 multipleSelect.methods = Constants.METHODS;
 
 // add it to the window object so it can be used as standalone
-if (typeof window !== 'undefined') {
+if (window !== undefined) {
   window.multipleSelect = multipleSelect;
 }

packages/multiple-select-vanilla/src/services/binding-event.service.ts

@@ -56,7 +56,7 @@ export class BindingEventService {
   ) {
     if (elementOrElements) {
       const elements = Array.isArray(elementOrElements) ? elementOrElements : [elementOrElements];
-      const eventNames = Array.isArray(eventNameOrNames) ? eventNameOrNames || '' : [eventNameOrNames || ''];
+      const eventNames = Array.isArray(eventNameOrNames) ? eventNameOrNames : [eventNameOrNames || ''];
 
       for (const element of elements) {
         if (!listener) {
@@ -94,8 +94,7 @@ export class BindingEventService {
     } else {
       // unbind everything
       while (this._boundedEvents.length > 0) {
-        const boundedEvent = this._boundedEvents.pop() as ElementEventListener;
-        const { element, eventName, listener } = boundedEvent;
+        const { element, eventName, listener } = this._boundedEvents.pop() as ElementEventListener;
         this.unbind(element, eventName, listener);
       }
     }

packages/multiple-select-vanilla/src/services/virtual-scroll.ts

@@ -111,10 +111,7 @@ export class VirtualScroll {
   protected getNum() {
     this.scrollTop = this.scrollEl.scrollTop;
     const blockSize = (this.clusterHeight || 0) - (this.blockHeight || 0);
-    if (blockSize) {
-      return Math.floor(this.scrollTop / blockSize) || 0;
-    }
-    return 0;
+    return blockSize ? Math.floor(this.scrollTop / blockSize) || 0 : 0;
   }
 
   protected initData(rows: HtmlStruct[], num: number) {