Add _.meanBy.

test/test.js

@@ -12010,6 +12010,19 @@
       }
     });
 
+    QUnit.test('`_.meanBy` should use `_.iteratee` internally', function(assert) {
+      assert.expect(1);
+
+      if (!isModularize) {
+        _.iteratee = getPropA;
+        assert.strictEqual(_.meanBy(objects), 2 / 3);
+        _.iteratee = iteratee;
+      }
+      else {
+        skipAssert(assert);
+      }
+    });
+
     QUnit.test('`_.minBy` should use `_.iteratee` internally', function(assert) {
       assert.expect(1);
 
@@ -13958,6 +13971,44 @@
 
   /*--------------------------------------------------------------------------*/
 
+  QUnit.module('lodash.meanBy');
+
+  (function() {
+    var objects = [{ 'a': 2 }, { 'a': 3 }, { 'a': 1 }];
+
+    QUnit.test('should work with an `iteratee` argument', function(assert) {
+      assert.expect(1);
+
+      var actual = _.meanBy(objects, function(object) {
+        return object.a;
+      });
+
+      assert.deepEqual(actual, 2);
+    });
+
+    QUnit.test('should provide the correct `iteratee` arguments', function(assert) {
+      assert.expect(1);
+
+      var args;
+
+      _.meanBy(objects, function() {
+        args || (args = slice.call(arguments));
+      });
+
+      assert.deepEqual(args, [{ 'a': 2 }]);
+    });
+
+    QUnit.test('should work with "_.property" shorthands', function(assert) {
+      assert.expect(2);
+
+      var arrays = [[2], [3], [1]];
+      assert.strictEqual(_.meanBy(arrays, 0), 2);
+      assert.strictEqual(_.meanBy(objects, 'a'), 2);
+    });
+  }());
+
+  /*--------------------------------------------------------------------------*/
+
   QUnit.module('lodash.memoize');
 
   (function() {
@@ -25146,7 +25197,7 @@
     var acceptFalsey = lodashStable.difference(allMethods, rejectFalsey);
 
     QUnit.test('should accept falsey arguments', function(assert) {
-      assert.expect(307);
+      assert.expect(308);
 
       var emptyArrays = lodashStable.map(falsey, alwaysEmptyArray);