feat: allow removing of zeroes for durations

src/duration.js

@@ -862,6 +862,16 @@ export default class Duration {
     return clone(this, { values: negated }, true);
   }
 
+  /**
+   * Removes all units with values equal to 0 from this Duration.
+   * @example Duration.fromObject({ years: 2, days: 0, hours: 0, minutes: 0 }).removeZeroes().toObject() //=> { years: 2 }
+   * @return {Duration}
+   */
+  removeZeroes() {
+    const vals = removeZeroes(this.toObject());
+    return clone(this, { values: vals }, true);
+  }
+
   /**
    * Get the years.
    * @type {number}

test/duration/units.test.js

@@ -359,3 +359,23 @@ test("Duration#valueOf value of the duration with lower and higher order units",
   const dur = Duration.fromObject({ days: 2, seconds: 1 });
   expect(dur.valueOf()).toBe(172801000);
 });
+
+//------
+// #removeZeroes()
+//-------
+
+test("Duration#removeZeroes removes zero units", () => {
+  expect(Duration.fromObject({ years: 2, days: 12, hours: 0 }).removeZeroes().toObject()).toEqual({
+    years: 2,
+    days: 12,
+  });
+  expect(
+    Duration.fromObject({ years: 2, days: 12, weeks: 0, hours: 0, milliseconds: 1 })
+      .removeZeroes()
+      .toObject()
+  ).toEqual({
+    years: 2,
+    days: 12,
+    milliseconds: 1,
+  });
+});