Improving performance of posting a comment by reducing memory + CPU

2 files changed, 7 insertions, 21 deletions

diff --git a/app/assets/javascripts/notes/stores/mutations.js b/app/assets/javascripts/notes/stores/mutations.js
index ab6a95e2601..e1b159142c9 100644
--- a/app/assets/javascripts/notes/stores/mutations.js
+++ b/app/assets/javascripts/notes/stores/mutations.js
@@ -174,27 +174,19 @@ export default {
 
   [types.UPDATE_NOTE](state, note) {
     const noteObj = utils.findNoteObjectById(state.discussions, note.discussion_id);
-
     if (noteObj.individual_note) {
       noteObj.notes.splice(0, 1, note);
     } else {
       const comment = utils.findNoteObjectById(noteObj.notes, note.id);
-      noteObj.notes.splice(noteObj.notes.indexOf(comment), 1, note);
+      Object.assign(comment, note);
     }
   },
 
   [types.UPDATE_DISCUSSION](state, noteData) {
     const note = noteData;
-    let index = 0;
-
-    state.discussions.forEach((n, i) => {
-      if (n.id === note.id) {
-        index = i;
-      }
-    });
-
+    const selectedDiscussion = state.discussions.find(n => n.id === note.id);
     note.expanded = true; // override expand flag to prevent collapse
-    state.discussions.splice(index, 1, note);
+    Object.assign(selectedDiscussion, note);
   },
 
   [types.CLOSE_ISSUE](state) {
@@ -215,12 +207,9 @@ export default {
 
   [types.SET_DISCUSSION_DIFF_LINES](state, { discussionId, diffLines }) {
     const discussion = utils.findNoteObjectById(state.discussions, discussionId);
-    const index = state.discussions.indexOf(discussion);
 
-    const discussionWithDiffLines = Object.assign({}, discussion, {
+    Object.assign(discussion, {
       truncated_diff_lines: diffLines,
     });
-
-    state.discussions.splice(index, 1, discussionWithDiffLines);
   },
 };
diff --git a/app/assets/javascripts/notes/stores/utils.js b/app/assets/javascripts/notes/stores/utils.js
index a0e096ebfaf..c4a812c5af4 100644
--- a/app/assets/javascripts/notes/stores/utils.js
+++ b/app/assets/javascripts/notes/stores/utils.js
@@ -2,13 +2,11 @@ import AjaxCache from '~/lib/utils/ajax_cache';
 
 const REGEX_QUICK_ACTIONS = /^\/\w+.*$/gm;
 
-export const findNoteObjectById = (notes, id) =>
-  notes.filter(n => n.id === id)[0];
+export const findNoteObjectById = (notes, id) => notes.find(n => n.id === id);
 
 export const getQuickActionText = note => {
   let text = 'Applying command';
-  const quickActions =
-    AjaxCache.get(gl.GfmAutoComplete.dataSources.commands) || [];
+  const quickActions = AjaxCache.get(gl.GfmAutoComplete.dataSources.commands) || [];
 
   const executedCommands = quickActions.filter(command => {
     const commandRegex = new RegExp(`/${command.name}`);
@@ -29,5 +27,4 @@ export const getQuickActionText = note => {
 
 export const hasQuickActions = note => REGEX_QUICK_ACTIONS.test(note);
 
-export const stripQuickActions = note =>
-  note.replace(REGEX_QUICK_ACTIONS, '').trim();
+export const stripQuickActions = note => note.replace(REGEX_QUICK_ACTIONS, '').trim();