Optimize Emoji Sprite Handling

app/assets/javascripts/behaviors/gl_emoji.js

@@ -7,27 +7,24 @@ export default function installGlEmojiElement() {
   const GlEmojiElementProto = Object.create(HTMLElement.prototype);
   GlEmojiElementProto.createdCallback = function createdCallback() {
     const emojiUnicode = this.textContent.trim();
-    const {
-      name,
-      unicodeVersion,
-      fallbackSrc,
-      fallbackSpriteClass,
-    } = this.dataset;
+    const { name, unicodeVersion, fallbackSrc, fallbackSpriteClass } = this.dataset;
 
-    const isEmojiUnicode = this.childNodes && Array.prototype.every.call(
-      this.childNodes,
-      childNode => childNode.nodeType === 3,
-    );
+    const isEmojiUnicode =
+      this.childNodes &&
+      Array.prototype.every.call(this.childNodes, childNode => childNode.nodeType === 3);
     const hasImageFallback = fallbackSrc && fallbackSrc.length > 0;
     const hasCssSpriteFalback = fallbackSpriteClass && fallbackSpriteClass.length > 0;
 
-    if (
-      emojiUnicode &&
-      isEmojiUnicode &&
-      !isEmojiUnicodeSupported(emojiUnicode, unicodeVersion)
-    ) {
+    if (emojiUnicode && isEmojiUnicode && !isEmojiUnicodeSupported(emojiUnicode, unicodeVersion)) {
       // CSS sprite fallback takes precedence over image fallback
       if (hasCssSpriteFalback) {
+        if (!gon.emoji_sprites_css_added && gon.emoji_sprites_css_path) {
+          const emojiSpriteLinkTag = document.createElement('link');
+          emojiSpriteLinkTag.setAttribute('rel', 'stylesheet');
+          emojiSpriteLinkTag.setAttribute('href', gon.emoji_sprites_css_path);
+          document.head.appendChild(emojiSpriteLinkTag);
+          gon.emoji_sprites_css_added = true;
+        }
         // IE 11 doesn't like adding multiple at once :(
         this.classList.add('emoji-icon');
         this.classList.add(fallbackSpriteClass);

app/assets/javascripts/emoji/index.js

@@ -34,7 +34,7 @@ export function getEmojiCategoryMap() {
       symbols: [],
       flags: [],
     };
-    Object.keys(emojiMap).forEach((name) => {
+    Object.keys(emojiMap).forEach(name => {
       const emoji = emojiMap[name];
       if (emojiCategoryMap[emoji.category]) {
         emojiCategoryMap[emoji.category].push(name);
@@ -79,7 +79,9 @@ export function glEmojiTag(inputName, options) {
     classList.push(fallbackSpriteClass);
   }
   const classAttribute = classList.length > 0 ? `class="${classList.join(' ')}"` : '';
-  const fallbackSpriteAttribute = opts.sprite ? `data-fallback-sprite-class="${fallbackSpriteClass}"` : '';
+  const fallbackSpriteAttribute = opts.sprite
+    ? `data-fallback-sprite-class="${fallbackSpriteClass}"`
+    : '';
   let contents = emojiInfo.moji;
   if (opts.forceFallback && !opts.sprite) {
     contents = emojiImageTag(name, fallbackImageSrc);

app/assets/javascripts/emoji/support/unicode_support_map.js

@@ -54,7 +54,8 @@ const unicodeSupportTestMap = {
 function checkPixelInImageDataArray(pixelOffset, imageDataArray) {
   // `4 *` because RGBA
   const indexOffset = 4 * pixelOffset;
-  const hasColor = imageDataArray[indexOffset + 0] ||
+  const hasColor =
+    imageDataArray[indexOffset + 0] ||
     imageDataArray[indexOffset + 1] ||
     imageDataArray[indexOffset + 2];
   const isVisible = imageDataArray[indexOffset + 3];
@@ -75,23 +76,23 @@ const chromeVersion = chromeMatches && chromeMatches[1] && parseInt(chromeMatche
 const fontSize = 16;
 function generateUnicodeSupportMap(testMap) {
   const testMapKeys = Object.keys(testMap);
-  const numTestEntries = testMapKeys
-    .reduce((list, testKey) => list.concat(testMap[testKey]), []).length;
+  const numTestEntries = testMapKeys.reduce((list, testKey) => list.concat(testMap[testKey]), [])
+    .length;
 
   const canvas = document.createElement('canvas');
   (window.gl || window).testEmojiUnicodeSupportMapCanvas = canvas;
   const ctx = canvas.getContext('2d');
-  canvas.width = (2 * fontSize);
-  canvas.height = (numTestEntries * fontSize);
+  canvas.width = 2 * fontSize;
+  canvas.height = numTestEntries * fontSize;
   ctx.fillStyle = '#000000';
   ctx.textBaseline = 'middle';
   ctx.font = `${fontSize}px "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol"`;
   // Write each emoji to the canvas vertically
   let writeIndex = 0;
-  testMapKeys.forEach((testKey) => {
+  testMapKeys.forEach(testKey => {
     const testEntry = testMap[testKey];
-    [].concat(testEntry).forEach((emojiUnicode) => {
-      ctx.fillText(emojiUnicode, 0, (writeIndex * fontSize) + (fontSize / 2));
+    [].concat(testEntry).forEach(emojiUnicode => {
+      ctx.fillText(emojiUnicode, 0, writeIndex * fontSize + fontSize / 2);
       writeIndex += 1;
     });
   });
@@ -99,29 +100,25 @@ function generateUnicodeSupportMap(testMap) {
   // Read from the canvas
   const resultMap = {};
   let readIndex = 0;
-  testMapKeys.forEach((testKey) => {
+  testMapKeys.forEach(testKey => {
     const testEntry = testMap[testKey];
     // This needs to be a `reduce` instead of `every` because we need to
     // keep the `readIndex` in sync from the writes by running all entries
-    const isTestSatisfied = [].concat(testEntry).reduce((isSatisfied) => {
+    const isTestSatisfied = [].concat(testEntry).reduce(isSatisfied => {
       // Sample along the vertical-middle for a couple of characters
-      const imageData = ctx.getImageData(
-          0,
-          (readIndex * fontSize) + (fontSize / 2),
-          2 * fontSize,
-          1,
-        ).data;
+      const imageData = ctx.getImageData(0, readIndex * fontSize + fontSize / 2, 2 * fontSize, 1)
+        .data;
 
       let isValidEmoji = false;
       for (let currentPixel = 0; currentPixel < 64; currentPixel += 1) {
         const isLookingAtFirstChar = currentPixel < fontSize;
-        const isLookingAtSecondChar = currentPixel >= (fontSize + (fontSize / 2));
+        const isLookingAtSecondChar = currentPixel >= fontSize + fontSize / 2;
         // Check for the emoji somewhere along the row
         if (isLookingAtFirstChar && checkPixelInImageDataArray(currentPixel, imageData)) {
           isValidEmoji = true;
 
-        // Check to see that nothing is rendered next to the first character
-        // to ensure that the ZWJ sequence rendered as one piece
+          // Check to see that nothing is rendered next to the first character
+          // to ensure that the ZWJ sequence rendered as one piece
         } else if (isLookingAtSecondChar && checkPixelInImageDataArray(currentPixel, imageData)) {
           isValidEmoji = false;
           break;
@@ -170,7 +167,10 @@ export default function getUnicodeSupportMap() {
     if (isLocalStorageAvailable) {
       window.localStorage.setItem('gl-emoji-version', GL_EMOJI_VERSION);
       window.localStorage.setItem('gl-emoji-user-agent', navigator.userAgent);
-      window.localStorage.setItem('gl-emoji-unicode-support-map', JSON.stringify(unicodeSupportMap));
+      window.localStorage.setItem(
+        'gl-emoji-unicode-support-map',
+        JSON.stringify(unicodeSupportMap),
+      );
     }
   }
 

app/assets/stylesheets/framework.scss

-@import "framework/variables";
-@import "framework/mixins";
+@import 'framework/variables';
+@import 'framework/mixins';
 @import 'framework/tw_bootstrap_variables';
 @import 'framework/tw_bootstrap';
-@import "framework/layout";
+@import 'framework/layout';
 
-@import "framework/animations";
-@import "framework/vue_transitions";
-@import "framework/avatar";
-@import "framework/asciidoctor";
-@import "framework/banner";
-@import "framework/blocks";
-@import "framework/buttons";
-@import "framework/badges";
-@import "framework/calendar";
-@import "framework/callout";
-@import "framework/common";
-@import "framework/dropdowns";
-@import "framework/files";
-@import "framework/filters";
-@import "framework/flash";
-@import "framework/forms";
-@import "framework/gfm";
-@import "framework/gitlab_theme";
-@import "framework/header";
-@import "framework/highlight";
-@import "framework/issue_box";
-@import "framework/jquery";
-@import "framework/lists";
-@import "framework/logo";
-@import "framework/markdown_area";
-@import "framework/media_object";
-@import "framework/mobile";
-@import "framework/modal";
-@import "framework/pagination";
-@import "framework/panels";
-@import "framework/popup";
-@import "framework/secondary_navigation_elements";
-@import "framework/selects";
-@import "framework/sidebar";
-@import "framework/contextual_sidebar";
-@import "framework/tables";
-@import "framework/notes";
-@import "framework/tabs";
-@import "framework/timeline";
-@import "framework/tooltips";
-@import "framework/toggle";
-@import "framework/typography";
-@import "framework/zen";
-@import "framework/blank";
-@import "framework/wells";
-@import "framework/page_header";
-@import "framework/awards";
-@import "framework/images";
-@import "framework/broadcast_messages";
-@import "framework/emojis";
-@import "framework/emoji_sprites";
-@import "framework/icons";
-@import "framework/snippets";
-@import "framework/memory_graph";
-@import "framework/responsive_tables";
-@import "framework/stacked_progress_bar";
-@import "framework/ci_variable_list";
-@import "framework/feature_highlight";
+@import 'framework/animations';
+@import 'framework/vue_transitions';
+@import 'framework/avatar';
+@import 'framework/asciidoctor';
+@import 'framework/banner';
+@import 'framework/blocks';
+@import 'framework/buttons';
+@import 'framework/badges';
+@import 'framework/calendar';
+@import 'framework/callout';
+@import 'framework/common';
+@import 'framework/dropdowns';
+@import 'framework/files';
+@import 'framework/filters';
+@import 'framework/flash';
+@import 'framework/forms';
+@import 'framework/gfm';
+@import 'framework/gitlab_theme';
+@import 'framework/header';
+@import 'framework/highlight';
+@import 'framework/issue_box';
+@import 'framework/jquery';
+@import 'framework/lists';
+@import 'framework/logo';
+@import 'framework/markdown_area';
+@import 'framework/media_object';
+@import 'framework/mobile';
+@import 'framework/modal';
+@import 'framework/pagination';
+@import 'framework/panels';
+@import 'framework/popup';
+@import 'framework/secondary_navigation_elements';
+@import 'framework/selects';
+@import 'framework/sidebar';
+@import 'framework/contextual_sidebar';
+@import 'framework/tables';
+@import 'framework/notes';
+@import 'framework/tabs';
+@import 'framework/timeline';
+@import 'framework/tooltips';
+@import 'framework/toggle';
+@import 'framework/typography';
+@import 'framework/zen';
+@import 'framework/blank';
+@import 'framework/wells';
+@import 'framework/page_header';
+@import 'framework/awards';
+@import 'framework/images';
+@import 'framework/broadcast_messages';
+@import 'framework/emojis';
+@import 'framework/icons';
+@import 'framework/snippets';
+@import 'framework/memory_graph';
+@import 'framework/responsive_tables';
+@import 'framework/stacked_progress_bar';
+@import 'framework/ci_variable_list';
+@import 'framework/feature_highlight';

config/application.rb

@@ -115,6 +115,7 @@ module Gitlab
     config.assets.precompile << "test.css"
     config.assets.precompile << "snippets.css"
     config.assets.precompile << "locale/**/app.js"
+    config.assets.precompile << "emoji_sprites.css"
 
     # Import gitlab-svgs directly from vendored directory
     config.assets.paths << "#{config.root}/node_modules/@gitlab-org/gitlab-svgs/dist"

lib/gitlab/gon_helper.rb

@@ -19,6 +19,7 @@ module Gitlab
       gon.gitlab_logo            = ActionController::Base.helpers.asset_path('gitlab_logo.png')
       gon.sprite_icons           = IconsHelper.sprite_icon_path
       gon.sprite_file_icons      = IconsHelper.sprite_file_icons_path
+      gon.emoji_sprites_css_path = ActionController::Base.helpers.stylesheet_path('emoji_sprites')
       gon.test_env               = Rails.env.test?
       gon.suggested_label_colors = LabelsHelper.suggested_colors