Use a named option rather than a boolean flag

js/ui/map.js

@@ -652,12 +652,14 @@ class Map extends Camera {
  *
  * @param {Object|string} style A JSON object conforming to the schema described in the
  * [Mapbox Style Specification](https://mapbox.com/mapbox-gl-style-spec/), or a URL to such JSON.
- * @param {boolean} forceNoDiff Force a 'full' update, removing the current style and adding building the given one instead of attempting a diff-based update.
+ * @param {Object} [options]
+ * @param {boolean} [options.diff=true] If false, force a 'full' update, removing the current style
+ * and adding building the given one instead of attempting a diff-based update.
  * @returns {Map} `this`
  * @see [Change a map's style](https://www.mapbox.com/mapbox-gl-js/example/setstyle/)
  */
- setStyle(style, forceNoDiff) {
- const shouldTryDiff = !forceNoDiff && this.style && style &&
+ setStyle(style, options) {
+ const shouldTryDiff = (!options || options.diff !== false) && this.style && style &&
  !(style instanceof Style) && typeof style !== 'string';
  if (shouldTryDiff) {
  try {

test/js/ui/map.test.js

@@ -300,15 +300,15 @@ test('Map', (t) => {
  t.end();
  });
 
- t.test('creates a new Style if forceNoDiff parameter is set', (t) => {
+ t.test('creates a new Style if diff option is false', (t) => {
  const style = createStyle();
  const map = createMap({ style: style });
  t.stub(map.style, 'setState', () => {
  t.fail();
  });
 
  const previousStyle = map.style;
- map.setStyle(style, true);
+ map.setStyle(style, {diff: false});
  t.ok(map.style && map.style !== previousStyle);
  t.end();
  });