Adding trigger and tests.

index.js

@@ -84,6 +84,19 @@ function debounce(function_, wait = 100, options = {}) {
 		timeoutId = undefined;
 	};
 
+	debounced.trigger = () => {
+		const callContext = storedContext;
+		const callArguments = storedArguments;
+		storedContext = undefined;
+		storedArguments = undefined;
+		result = function_.apply(callContext, callArguments);
+
+		if (timeoutId) {
+			clearTimeout(timeoutId);
+			timeoutId = undefined;
+		}
+	};
+
 	return debounced;
 }
 

test.js

@@ -397,3 +397,20 @@ test('calling flush method without any scheduled execution', async () => {
 
 	assert.strictEqual(callback.callCount, 0, 'Callback should not be executed if flush is called without any scheduled execution');
 });
+
+test('calling the trigger function should run it immediately', async () => {
+	const clock = sinon.useFakeTimers();
+	const callback = sinon.spy();
+	const fn = debounce(callback, 100);
+
+	fn();
+	fn.trigger();
+
+	assert.strictEqual(callback.callCount, 1, 'Callback should be called once when using trigger method');
+
+	clock.tick(100);
+
+	assert.strictEqual(callback.callCount, 1, 'Callback should stay at one call after timeout');
+
+	clock.restore();
+});