From 761b877626e9f056464f3ef12923d0bb768c276b Mon Sep 17 00:00:00 2001
From: Pat O'Neill <pgoneill@gmail.com>
Date: Fri, 2 Dec 2016 15:51:41 -0500
Subject: [PATCH] feat: Eliminate lodash-compat as a dependency, rewrite
 mergeOptions (#3760)

---
 build/grunt.js                                |  2 +-
 build/options-customizer.js                   |  2 +-
 package.json                                  |  2 +-
 .../progress-control/mouse-time-display.js    |  3 +-
 src/js/utils/fn.js                            | 33 ++++++++-
 src/js/utils/merge-options.js                 | 73 +++++++------------
 src/js/video.js                               |  9 ++-
 7 files changed, 66 insertions(+), 58 deletions(-)

diff --git a/build/grunt.js b/build/grunt.js
index 698b6cffce..ebc4df725b 100644
--- a/build/grunt.js
+++ b/build/grunt.js
@@ -5,7 +5,7 @@ import npmRun from 'npm-run';
 module.exports = function(grunt) {
   require('time-grunt')(grunt);
 
-  let _ = require('lodash-compat');
+  let _ = require('lodash');
   let pkg = grunt.file.readJSON('package.json');
   let license = grunt.file.read('build/license-header.txt');
   let bannerCommonData = _.pick(pkg, ['version', 'copyright']);
diff --git a/build/options-customizer.js b/build/options-customizer.js
index 5257e73d6f..a3db5cd3aa 100644
--- a/build/options-customizer.js
+++ b/build/options-customizer.js
@@ -1,4 +1,4 @@
-import _ from 'lodash-compat';
+import _ from 'lodash';
 /**
  * Customizes _.merge behavior in `gruntOptions` to concatenate
  * arrays. This can be overridden on a per-call basis to
diff --git a/package.json b/package.json
index 6cc3b5fa11..54e5351d65 100644
--- a/package.json
+++ b/package.json
@@ -34,7 +34,6 @@
   "dependencies": {
     "babel-runtime": "^6.9.2",
     "global": "4.3.0",
-    "lodash-compat": "3.10.2",
     "safe-json-parse": "4.0.0",
     "tsml": "1.0.1",
     "videojs-font": "2.0.0",
@@ -101,6 +100,7 @@
     "karma-safari-launcher": "^1.0.0",
     "karma-sinon": "^1.0.5",
     "load-grunt-tasks": "^3.1.0",
+    "lodash": "^4.16.6",
     "markdown-table": "^1.0.0",
     "npm-run": "^4.1.0",
     "proxyquireify": "^3.0.0",
diff --git a/src/js/control-bar/progress-control/mouse-time-display.js b/src/js/control-bar/progress-control/mouse-time-display.js
index 158cbc300c..837f5c4244 100644
--- a/src/js/control-bar/progress-control/mouse-time-display.js
+++ b/src/js/control-bar/progress-control/mouse-time-display.js
@@ -5,7 +5,6 @@ import Component from '../../component.js';
 import * as Dom from '../../utils/dom.js';
 import * as Fn from '../../utils/fn.js';
 import formatTime from '../../utils/format-time.js';
-import throttle from 'lodash-compat/function/throttle';
 import computedStyle from '../../utils/computed-style.js';
 
 /**
@@ -44,7 +43,7 @@ class MouseTimeDisplay extends Component {
     this.update(0, 0);
 
     player.on('ready', () => {
-      this.on(player.controlBar.progressControl.el(), 'mousemove', throttle(Fn.bind(this, this.handleMouseMove), 25));
+      this.on(player.controlBar.progressControl.el(), 'mousemove', Fn.throttle(Fn.bind(this, this.handleMouseMove), 25));
     });
   }
 
diff --git a/src/js/utils/fn.js b/src/js/utils/fn.js
index 0151419d93..4ad087be39 100644
--- a/src/js/utils/fn.js
+++ b/src/js/utils/fn.js
@@ -27,7 +27,7 @@ export const bind = function(context, fn, uid) {
   }
 
   // Create the new function that changes the context
-  const ret = function() {
+  const bound = function() {
     return fn.apply(context, arguments);
   };
 
@@ -37,7 +37,34 @@ export const bind = function(context, fn, uid) {
   // it will remove both because they both have the same guid.
   // when using this, you need to use the bind method when you remove the listener as well.
   // currently used in text tracks
-  ret.guid = (uid) ? uid + '_' + fn.guid : fn.guid;
+  bound.guid = (uid) ? uid + '_' + fn.guid : fn.guid;
 
-  return ret;
+  return bound;
+};
+
+/**
+ * Wraps the given function, `fn`, with a new function that only invokes `fn`
+ * at most once per every `wait` milliseconds.
+ *
+ * @param  {Function} fn
+ *         The function to be throttled.
+ *
+ * @param  {Number}   wait
+ *         The number of milliseconds by which to throttle.
+ *
+ * @return {Function}
+ */
+export const throttle = function(fn, wait) {
+  let last;
+
+  const throttled = function(...args) {
+    const now = Date.now();
+
+    if (now - last >= wait) {
+      fn(...args);
+      last = now;
+    }
+  };
+
+  return throttled;
 };
diff --git a/src/js/utils/merge-options.js b/src/js/utils/merge-options.js
index 8ecd69a6cb..73a012bf14 100644
--- a/src/js/utils/merge-options.js
+++ b/src/js/utils/merge-options.js
@@ -2,62 +2,39 @@
  * @file merge-options.js
  * @module merge-options
  */
-import merge from 'lodash-compat/object/merge';
-import {isPlain} from './obj';
+import {each, isPlain} from './obj';
 
 /**
- * Merge customizer. video.js simply overwrites non-simple objects
- * (like arrays) instead of attempting to overlay them.
+ * Deep-merge one or more options objects, recursively merging **only** plain
+ * object properties.
  *
- * @param {Mixed} destination
- *        The merge destination
- *
- * @param {Mixed} source
- *        A merge source.
- *
- * @retun {Mixed}
- *        The source and destination merged.
- *
- * @see https://lodash.com/docs#merge
- */
-function customizer(destination, source) {
-  // If we're not working with a plain object, copy the value as is
-  // If source is an array, for instance, it will replace destination
-  if (!isPlain(source)) {
-    return source;
-  }
-
-  // If the new value is a plain object but the first object value is not
-  // we need to create a new object for the first object to merge with.
-  // This makes it consistent with how merge() works by default
-  // and also protects from later changes the to first object affecting
-  // the second object's values.
-  if (!isPlain(destination)) {
-    return mergeOptions(source);
-  }
-}
-
-/**
- * Merge one or more options objects, recursively merging **only**
- * plain object properties.  Previously `deepMerge`.
- *
- * @param  {Object[]} source
- *         One or more objects to merge
+ * @param   {Object[]} sources
+ *          One or more objects to merge into a new object.
  *
  * @returns {Object}
- *          a new object that is the union of all
+ *          A new object that is the merged result of all sources.
  */
-export default function mergeOptions(...objects) {
+export default function mergeOptions(...sources) {
+  const result = {};
+
+  sources.forEach(source => {
+    if (!source) {
+      return;
+    }
 
-  // unshift an empty object into the front of the call as the target
-  // of the merge
-  objects.unshift({});
+    each(source, (value, key) => {
+      if (!isPlain(value)) {
+        result[key] = value;
+        return;
+      }
 
-  // customize conflict resolution to match our historical merge behavior
-  objects.push(customizer);
+      if (!isPlain(result[key])) {
+        result[key] = {};
+      }
 
-  merge.apply(null, objects);
+      result[key] = mergeOptions(result[key], value);
+    });
+  });
 
-  // return the mutated result object
-  return objects[0];
+  return result;
 }
diff --git a/src/js/video.js b/src/js/video.js
index 48ae816dfd..0e8d981e77 100644
--- a/src/js/video.js
+++ b/src/js/video.js
@@ -29,7 +29,6 @@ import * as Url from './utils/url.js';
 import {isObject} from './utils/obj';
 import computedStyle from './utils/computed-style.js';
 import extendFn from './extend.js';
-import merge from 'lodash-compat/object/merge';
 import xhr from 'xhr';
 
 // Include the built-in techs
@@ -498,7 +497,13 @@ videojs.plugin = plugin;
  */
 videojs.addLanguage = function(code, data) {
   code = ('' + code).toLowerCase();
-  return merge(videojs.options.languages, { [code]: data })[code];
+
+  videojs.options.languages = mergeOptions(
+    videojs.options.languages,
+    {[code]: data}
+  );
+
+  return videojs.options.languages[code];
 };
 
 /**