Implement Iterator.zip() - static method for zipping iterators

PR-URL: #342

CHANGELOG.md

@@ -23,6 +23,7 @@ and this project adheres to
   (finding minimum, maximum, or using a custom condition appropriately).
 - `Iterator#partition()` to allow splitting iterator values into
   multiple arrays.
+- `Iterator.zip()` - static method for zipping iterators.
 
 ### Changed
 

README.md

@@ -138,6 +138,7 @@ $ npm install @metarhia/common
   - [Int64.prototype.xor](#int64prototypexorb)
 - [Iterator](#class-iterator)
   - [Iterator.range](#iteratorrangestart-stop-step)
+  - [Iterator.zip](#iteratorzipiterators)
   - [Iterator.prototype.constructor](#iteratorprototypeconstructorbase)
   - [Iterator.prototype.apply](#iteratorprototypeapplyfn)
   - [Iterator.prototype.chain](#iteratorprototypechainiterators)
@@ -1058,6 +1059,14 @@ _Returns:_ `<Iterator>`
 
 Create iterator iterating over the range
 
+#### Iterator.zip(...iterators)
+
+- `iterators`: [`<Array>`][array]
+
+_Returns:_ `<Iterator>`
+
+Create iterator by zipping multiple provided iterators into one
+
 #### Iterator.prototype.constructor(base)
 
 #### Iterator.prototype.apply(fn)

lib/iterator.js

@@ -309,6 +309,14 @@ class Iterator {
     return iter(res && res[Symbol.iterator] ? res : [res]);
   }
 
+  // Create iterator by zipping multiple provided iterators into one
+  // Signature: ...iterators
+  //   iterators <Array>
+  // Returns: <Iterator>
+  static zip(base, ...iterators) {
+    return new ZipIterator(toIterator(base), iterators);
+  }
+
   // Create iterator iterating over the range
   // Signature: start, stop[, step]
   //   start <number>

test/iterator.js

@@ -279,14 +279,14 @@ metatests.test('Iterator.flatMap with thisArg', test => {
   test.end();
 });
 
-metatests.test('Iterator.zip with single iterator', test => {
+metatests.test('Iterator#zip with single iterator', test => {
   const it = iter(array).take(1);
   const toZip = iter(array).skip(2);
   test.strictSame(it.zip(toZip).toArray(), [[1, 3]]);
   test.end();
 });
 
-metatests.test('Iterator.zip with multiple iterators', test => {
+metatests.test('Iterator#zip with multiple iterators', test => {
   const it = iter(array);
   const itr = iter(array).take(3);
   const iterator = iter(array).take(2);
@@ -297,6 +297,24 @@ metatests.test('Iterator.zip with multiple iterators', test => {
   test.end();
 });
 
+metatests.test('Iterator.zip with single iterator', test => {
+  const it1 = iter(array).take(1);
+  const it2 = iter(array).skip(2);
+  test.strictSame(Iterator.zip(it1, it2).toArray(), [[1, 3]]);
+  test.end();
+});
+
+metatests.test('Iterator.zip with multiple iterators', test => {
+  const it1 = iter(array);
+  const it2 = iter(array).take(3);
+  const it3 = iter(array).take(2);
+  test.strictSame(Iterator.zip(it1, it2, it3).toArray(), [
+    [1, 1, 1],
+    [2, 2, 2],
+  ]);
+  test.end();
+});
+
 metatests.test('Iterator.chain', test => {
   const it = iter(array).take(1);
   const itr = iter(array)