BREAKING CHANGE: change definition of throttle options

debounce.js

@@ -18,6 +18,6 @@ import throttle from './throttle';
  */
 export default function (delay, atBegin, callback) {
 	return callback === undefined
-		? throttle(delay, atBegin, false)
-		: throttle(delay, callback, atBegin !== false);
+		? throttle(delay, atBegin, { debounceMode: false })
+		: throttle(delay, callback, { debounceMode: atBegin !== false });
 }

test/index.js

@@ -46,7 +46,7 @@ function execManyTimes(each, complete) {
 
 module('throttle');
 
-test('delay, callback', function () {
+test('no option', function () {
 	expect(7);
 	stop();
 
@@ -97,7 +97,7 @@ test('delay, callback', function () {
 	);
 });
 
-test('delay, false, callback', function () {
+test('{ noTrailing: false }', function () {
 	expect(7);
 	stop();
 
@@ -107,7 +107,7 @@ test('delay, false, callback', function () {
 	let function_ = function (now) {
 		array.push(now - this);
 	};
-	let throttled = throttle(delay, false, function_);
+	let throttled = throttle(delay, function_, { noTrailing: false });
 
 	equals(
 		throttled.guid,
@@ -148,7 +148,7 @@ test('delay, false, callback', function () {
 	);
 });
 
-test('delay, true, callback', function () {
+test('{ noTrailing: true }', function () {
 	expect(7);
 	stop();
 
@@ -158,7 +158,7 @@ test('delay, true, callback', function () {
 	let function_ = function (now) {
 		array.push(now - this);
 	};
-	let throttled = throttle(delay, true, function_);
+	let throttled = throttle(delay, function_, { noTrailing: true });
 
 	equals(
 		throttled.guid,
@@ -204,9 +204,13 @@ test('cancel', function () {
 	stop();
 
 	let callCount = 0;
-	let throttled = throttle(delay * 100, false, function () {
-		callCount++;
-	});
+	let throttled = throttle(
+		delay * 100,
+		function () {
+			callCount++;
+		},
+		{ noTrailing: false }
+	);
 
 	equals(1, 1);
 

throttle.js

@@ -4,19 +4,22 @@
  * Throttle execution of a function. Especially useful for rate limiting
  * execution of handlers on events like resize and scroll.
  *
- * @param  {number}    delay -          A zero-or-greater delay in milliseconds. For event callbacks, values around 100 or 250 (or even higher) are most useful.
- * @param  {boolean}   [noTrailing] -   Optional, defaults to false. If noTrailing is true, callback will only execute every `delay` milliseconds while the
- *                                    throttled-function is being called. If noTrailing is false or unspecified, callback will be executed one final time
- *                                    after the last throttled-function call. (After the throttled-function has not been called for `delay` milliseconds,
- *                                    the internal counter is reset).
- * @param  {Function}  callback -       A function to be executed after delay milliseconds. The `this` context and all arguments are passed through, as-is,
- *                                    to `callback` when the throttled-function is executed.
- * @param  {boolean}   [debounceMode] - If `debounceMode` is true (at begin), schedule `clear` to execute after `delay` ms. If `debounceMode` is false (at end),
- *                                    schedule `callback` to execute after `delay` ms.
+ * @param  {number}    delay -                  A zero-or-greater delay in milliseconds. For event callbacks, values around 100 or 250 (or even higher)
+ *                                            are most useful.
+ * @param  {Function}  callback -               A function to be executed after delay milliseconds. The `this` context and all arguments are passed through,
+ *                                            as-is, to `callback` when the throttled-function is executed.
+ * @param  {object}    [options] -              An object to configure options.
+ * @param  {boolean}   [options.noTrailing] -   Optional, defaults to false. If noTrailing is true, callback will only execute every `delay` milliseconds
+ *                                            while the throttled-function is being called. If noTrailing is false or unspecified, callback will be executed
+ *                                            one final time after the last throttled-function call. (After the throttled-function has not been called for
+ *                                            `delay` milliseconds, the internal counter is reset).
+ * @param  {boolean}   [options.debounceMode] - If `debounceMode` is true (at begin), schedule `clear` to execute after `delay` ms. If `debounceMode` is
+ *                                            false (at end), schedule `callback` to execute after `delay` ms.
  *
  * @returns {Function}  A new, throttled, function.
  */
-export default function (delay, noTrailing, callback, debounceMode) {
+export default function (delay, callback, options) {
+	const { noTrailing = false, debounceMode = undefined } = options || {};
 	/*
 	 * After wrapper has stopped being called, this timeout ensures that
 	 * `callback` is executed at the proper times in `throttle` and `end`
@@ -41,13 +44,6 @@ export default function (delay, noTrailing, callback, debounceMode) {
 		cancelled = true;
 	}
 
-	// `noTrailing` defaults to falsy.
-	if (typeof noTrailing !== 'boolean') {
-		debounceMode = callback;
-		callback = noTrailing;
-		noTrailing = undefined;
-	}
-
 	/*
 	 * The `wrapper` function encapsulates all of the throttling / debouncing
 	 * functionality and when executed will limit the rate at which `callback`