fix(ui5-timepicker): fix firing "change" event for the same value (#1764)

Previously the TImePicker used to fire "change" event unconditionally upon "Submit" press. 
Now, the value is checked and if it is changed, the event will be fired.

Author: ilhan007

packages/main/src/TimePicker.js

@@ -281,8 +281,7 @@ class TimePicker extends UI5Element {
 	constructor() {
 		super();
 
-		this.readonly = false;
-		this.disabled = false;
+		this.prevValue = null;
 		this._isPickerOpen = false;
 		this.i18nBundle = getI18nBundle("@ui5/webcomponents");
 
@@ -531,9 +530,13 @@ class TimePicker extends UI5Element {
 		selectedDate.setMinutes(minutes);
 		selectedDate.setSeconds(seconds);
 
+		this.setPrevValue(this.value);
 		this.setValue(this.getFormat().format(selectedDate));
 
-		this.fireEvent("change", { value: this.value, valid: true });
+		if (this.prevValue !== this.value) {
+			this.fireEvent("change", { value: this.value, valid: true });
+			this.previousValue = this.value;
+		}
 
 		this.closePicker();
 	}
@@ -700,6 +703,12 @@ class TimePicker extends UI5Element {
 		}
 	}
 
+	setPrevValue(value) {
+		if (this.isValid(value)) {
+			this.prevValue = this.normalizeValue(value);
+		}
+	}
+
 	/**
 	 * Formats a Java Script date object into a string representing a locale date and time
 	 * according to the <code>formatPattern</code> property of the TimePicker instance

packages/main/test/pages/TimePicker.html

@@ -30,8 +30,8 @@
 
 		<br /><br />
 		<ui5-title>Test "change" event</ui5-title>
-		<ui5-timepicker id="timepickerChange"></ui5-timepicker>
-		<ui5-input id="changeResult"></ui5-input>
+		<ui5-timepicker id="timepickerChange" format-pattern="HH:mm" value="12:00"></ui5-timepicker>
+		<ui5-input id="changeResult" value="0"></ui5-input>
 
 		<br /><br />
 		<ui5-title>Test "input" event</ui5-title>
@@ -57,12 +57,12 @@
 
 		<script>
 				var counter = 0;
-				timepickerChange.addEventListener("change", function() {
+				timepickerChange.addEventListener("ui5-change", function() {
 					changeResult.value = ++counter;
 				});
 
 				var inputCounter = 0;
-				timepickerInput.addEventListener("input", function() {
+				timepickerInput.addEventListener("ui5-input", function() {
 					inputResult.value = ++inputCounter;
 				});
 

packages/main/test/specs/TimePicker.spec.js

@@ -71,6 +71,44 @@ describe("TimePicker general interaction", () => {
 		assert.notOk(slot.error, "cValue State message slot is working");
 	});
 
+	it("tests change event", () => {
+		const staticAreaItemClassName = browser.getStaticAreaItemClassName("#timepickerChange");
+		const timepicker = browser.$("#timepickerChange");
+		const icon = timepicker.shadow$("ui5-input").$("ui5-icon");
+		const changeResult = browser.$("#changeResult");
+
+		// act - submit the same time
+		icon.click();
+		const timepickerPopover = browser.$(`.${staticAreaItemClassName}`).shadow$("ui5-responsive-popover");
+		timepickerPopover.$("#submit").click();
+
+		// assert
+		assert.strictEqual(changeResult.getProperty("value"), "0", "Change not fired as expected");
+
+		// act - submit value after changing time
+		icon.click();
+		timepickerPopover.$(".ui5-timepicker-hours-wheelslider").setProperty("value", "10");
+		timepickerPopover.$("#submit").click();
+
+		// assert
+		assert.strictEqual(changeResult.getProperty("value"), "1", "Change fired as expected");
+
+		// act - submit the same time
+		icon.click();
+		timepickerPopover.$("#submit").click();
+
+		// assert
+		assert.strictEqual(changeResult.getProperty("value"), "1", "Change not fired as expected");
+
+		// act - submit value after changing time
+		icon.click();
+		timepickerPopover.$(".ui5-timepicker-hours-wheelslider").setProperty("value", "11");
+		timepickerPopover.$("#submit").click();
+
+		// assert
+		assert.strictEqual(changeResult.getProperty("value"), "2", "Change fired as expected");
+	});
+
 	it("tests value state", () => {
 		const timepicker = browser.$("#timepickerEmptyValue");
 		const button = browser.$("#testBtn");