feat: implement Iterator.zip() - static method for zipping iterators

ORIGINAL-PR-URL: metarhia/common#342
metarhia · Sep 13, 2020 · f2a3c1c · f2a3c1c
1 parent 2a2ea3a
commit f2a3c1c
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Showing 2 changed files with 28 additions and 2 deletions.
diff --git a/lib/iterator.js b/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>

diff --git a/test/iterator.js b/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)