fix(react): Support for adding css classes via className in Ionic React components (#18231)

* fix(react): adding classname to react props

* fix(react): updating rtl to latest to fix ts error

* fix(react): changes to support className

react/src/components/utils/attachEventProps.ts

@@ -0,0 +1,83 @@
+export function attachEventProps(node: HTMLElement, newProps: any, oldProps: any = {}) {
+  const className = getClassName(node.classList, newProps, oldProps);
+  if(className) {
+    node.className = className;
+  }
+
+  Object.keys(newProps).forEach(name => {
+    if (name === 'children' || name === 'style' || name === 'ref' || name === 'className') {
+      return;
+    }
+    if (name.indexOf('on') === 0 && name[2] === name[2].toUpperCase()) {
+      const eventName = name.substring(2);
+      const eventNameLc = eventName[0].toLowerCase() + eventName.substring(1);
+
+      if (!isCoveredByReact(eventNameLc)) {
+        syncEvent(node, eventNameLc, newProps[name]);
+      }
+    } else {
+      (node as any)[name] = newProps[name];
+    }
+  });
+}
+
+export function getClassName(classList: DOMTokenList, newProps: any, oldProps: any) {
+  // map the classes to Maps for performance
+  const currentClasses = arrayToMap(classList);
+  const incomingPropClasses = arrayToMap(newProps.className ? newProps.className.split(' ') : []);
+  const oldPropClasses = arrayToMap(oldProps.className ? oldProps.className.split(' ') : []);
+  const finalClassNames: string[] = [];
+  // loop through each of the current classes on the component
+  // to see if it should be a part of the classNames added
+  currentClasses.forEach((currentClass) => {
+    if (incomingPropClasses.has(currentClass)) {
+      // add it as its already included in classnames coming in from newProps
+      finalClassNames.push(currentClass);
+      incomingPropClasses.delete(currentClass);
+    }
+    else if (!oldPropClasses.has(currentClass)) {
+      // add it as it has NOT been removed by user
+      finalClassNames.push(currentClass);
+    }
+  });
+  incomingPropClasses.forEach(s => finalClassNames.push(s));
+  return finalClassNames.join(' ');
+}
+
+/**
+ * Checks if an event is supported in the current execution environment.
+ * @license Modernizr 3.0.0pre (Custom Build) | MIT
+ */
+export function isCoveredByReact(eventNameSuffix: string, doc: Document = document) {
+  const eventName = 'on' + eventNameSuffix;
+  let isSupported = eventName in doc;
+
+  if (!isSupported) {
+    const element = doc.createElement('div');
+    element.setAttribute(eventName, 'return;');
+    isSupported = typeof (<any>element)[eventName] === 'function';
+  }
+
+  return isSupported;
+}
+
+export function syncEvent(node: Element, eventName: string, newEventHandler: (e: Event) => any) {
+  const eventStore = (node as any).__events || ((node as any).__events = {});
+  const oldEventHandler = eventStore[eventName];
+
+  // Remove old listener so they don't double up.
+  if (oldEventHandler) {
+    node.removeEventListener(eventName, oldEventHandler);
+  }
+
+  // Bind new listener.
+  node.addEventListener(eventName, eventStore[eventName] = function handler(e: Event) {
+    newEventHandler.call(this, e);
+  });
+}
+
+function arrayToMap(arr: string[] | DOMTokenList) {
+  const map = new Map<string, string>();
+  arr.forEach((s: string) => map.set(s, s));
+  return map;
+}