1 files changed, 45 insertions, 0 deletions
diff --git a/spec/javascripts/extensions/array_spec.js.es6 b/spec/javascripts/extensions/array_spec.js.es6
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+++ b/spec/javascripts/extensions/array_spec.js.es6
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+/* eslint-disable space-before-function-paren, no-var */
+
+/*= require extensions/array */
+
+(function() {
+  describe('Array extensions', function() {
+    describe('first', function() {
+      return it('returns the first item', function() {
+        var arr;
+        arr = [0, 1, 2, 3, 4, 5];
+        return expect(arr.first()).toBe(0);
+      });
+    });
+    describe('last', function() {
+      return it('returns the last item', function() {
+        var arr;
+        arr = [0, 1, 2, 3, 4, 5];
+        return expect(arr.last()).toBe(5);
+      });
+    });
+
+    describe('find', function () {
+      beforeEach(() => {
+        this.arr = [0, 1, 2, 3, 4, 5];
+      });
+
+      it('returns the item that first passes the predicate function', () => {
+        expect(this.arr.find(item => item === 2)).toBe(2);
+      });
+
+      it('returns undefined if no items pass the predicate function', () => {
+        expect(this.arr.find(item => item === 6)).not.toBeDefined();
+      });
+
+      it('error when called on undefined or null', () => {
+        expect(Array.prototype.find.bind(undefined, item => item === 1)).toThrow();
+        expect(Array.prototype.find.bind(null, item => item === 1)).toThrow();
+      });
+
+      it('error when predicate is not a function', () => {
+        expect(Array.prototype.find.bind(this.arr, 1)).toThrow();
+      });
+    });
+  });
+}).call(this);