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@@ -0,0 +1,33 @@
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+/**
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+ * @license Copyright (c) 2003-2017, CKSource - Frederico Knabben. All rights reserved.
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+ * For licensing, see LICENSE.md.
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+ */
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+
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+import first from '../src/first';
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+
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+describe( 'utils', () => {
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+ describe( 'first', () => {
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+ it( 'should return first item', () => {
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+ const collection = [ 11, 22 ];
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+ const iterator = collection[ Symbol.iterator ]();
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+
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+ expect( first( iterator ) ).to.equal( 11 );
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+ } );
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+
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+ it( 'should return null if iterator is empty', () => {
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+ const collection = [];
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+ const iterator = collection[ Symbol.iterator ]();
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+
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+ expect( first( iterator ) ).to.be.null;
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+ } );
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+
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+ it( 'should consume the iterating item', () => {
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+ const collection = [ 11, 22 ];
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+ const iterator = collection[ Symbol.iterator ]();
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+
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+ first( iterator );
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+
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+ expect( iterator.next().value ).to.equal( 22 );
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+ } );
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+ } );
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+} );
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