feat: add isEmptyArray

Ref char0n#279

src/index.d.ts

@@ -38,6 +38,11 @@ declare namespace RamdaAdjunct {
          */
         isArray(val: any): val is Array<any>;
 
+        /**
+         * Checks if input value is an empty `Array`.
+         */
+        isEmptyArray(val: any): val is Array<any>;
+
         /**
          * Checks if input value is `Boolean`.
          */

src/index.js

@@ -9,6 +9,7 @@ export { default as isNull } from './isNull';
 export { default as isNotNull } from './isNotNull';
 export { default as isNotNil } from './isNotNil';
 export { default as isArray } from './isArray';
+export { default as isEmptyArray } from './isEmptyArray';
 export { default as isNotArray } from './isNotArray';
 export { default as isBoolean } from './isBoolean';
 export { default as isNotBoolean } from './isNotBoolean';

src/isEmptyArray.js

@@ -0,0 +1,29 @@
+import { both, isEmpty } from 'ramda';
+
+import isArray from './isArray';
+
+
+/**
+ * Checks if input value is an empty `Array`.
+ *
+ * @func isEmptyArray
+ * @memberOf RA
+ * @since {@link https://char0n.github.io/ramda-adjunct/2.4.0|v2.4.0}
+ * @category Type
+ * @sig * -> Boolean
+ * @param {*} val The value to test
+ * @return {Boolean}
+ * @see {@link RA.isNotEmptyArray|isNotEmptyArray}
+ * @example
+ *
+ * RA.isEmptyArray([]); // => true
+ * RA.isEmptyArray([42]); // => false
+ * RA.isEmptyArray({}); // => false
+ * RA.isEmptyArray(null); // => false
+ * RA.isEmptyArray(undefined); // => false
+ * RA.isEmptyArray(42); // => false
+ * RA.isEmptyArray('42'); // => false
+ */
+const isEmptyArray = both(isEmpty, isArray);
+
+export default isEmptyArray;

test/isEmptyArray.js

@@ -0,0 +1,21 @@
+import * as RA from '../src/index';
+import eq from './shared/eq';
+
+describe('isEmptyArray', function() {
+  it('tests a value to be an empty `Array`', function() {
+    eq(RA.isEmptyArray([]), true);
+    eq(RA.isEmptyArray(new Array()), true);
+    eq(RA.isEmptyArray(Array.prototype), true);
+
+    eq(RA.isEmptyArray([1]), false);
+    eq(RA.isEmptyArray(void 0), false);
+    eq(RA.isEmptyArray({}), false);
+    eq(RA.isEmptyArray(null), false);
+    eq(RA.isEmptyArray(undefined), false);
+    eq(RA.isEmptyArray(17), false);
+    eq(RA.isEmptyArray('Array'), false);
+    eq(RA.isEmptyArray(true), false);
+    eq(RA.isEmptyArray(false), false);
+    eq(RA.isEmptyArray({ __proto__: Array.prototype }), false);
+  });
+});