Added constants for Render values + Optimised for Loop

app/assets/javascripts/diffs/constants.js

@@ -25,3 +25,6 @@ export const CONTEXT_LINE_CLASS_NAME = 'diff-expanded';
 export const UNFOLD_COUNT = 20;
 export const COUNT_OF_AVATARS_IN_GUTTER = 3;
 export const LENGTH_OF_AVATAR_TOOLTIP = 17;
+
+export const LINES_TO_BE_RENDERED_DIRECTLY = 100;
+export const MAX_LINES_TO_BE_RENDERED = 2000;

app/assets/javascripts/diffs/store/mutations.js

@@ -2,6 +2,7 @@ import Vue from 'vue';
 import _ from 'underscore';
 import { convertObjectPropsToCamelCase } from '~/lib/utils/common_utils';
 import { findDiffFile, addLineReferences, removeMatchLine, addContextLines } from './utils';
+import { LINES_TO_BE_RENDERED_DIRECTLY, MAX_LINES_TO_BE_RENDERED } from '../constants';
 import * as types from './mutation_types';
 
 export default {
@@ -17,31 +18,40 @@ export default {
   [types.SET_DIFF_DATA](state, data) {
     const diffData = convertObjectPropsToCamelCase(data, { deep: true });
     let showingLines = 0;
-    diffData.diffFiles.forEach(file => {
+    const filesLength = diffData.diffFiles.length;
+    let i;
+    for (i = 0; i < filesLength; i += 1) {
+      const file = diffData.diffFiles[i];
       if (file.parallelDiffLines) {
-        file.parallelDiffLines.forEach(line => {
+        const linesLength = file.parallelDiffLines.length;
+        let u = 0;
+        for (u = 0; u < linesLength; u += 1) {
+          const line = file.parallelDiffLines[u];
           // eslint-disable-next-line no-param-reassign
           if (line.left) delete line.left.text;
           // eslint-disable-next-line no-param-reassign
           if (line.right) delete line.right.text;
-        });
+        }
       }
 
       if (file.highlightedDiffLines) {
-        file.highlightedDiffLines.forEach(line => {
+        const linesLength = file.highlightedDiffLines.length;
+        let u = 0;
+        for (u = 0; u < linesLength; u += 1) {
+          const line = file.highlightedDiffLines[u];
           // eslint-disable-next-line no-param-reassign
           delete line.text;
-        });
+        }
       }
 
       if (file.highlightedDiffLines) {
         showingLines += file.parallelDiffLines.length;
       }
       Object.assign(file, {
-        renderIt: showingLines < 200,
-        collapsed: file.text && showingLines > 2000,
-      });
+        renderIt: showingLines < LINES_TO_BE_RENDERED_DIRECTLY,
+        collapsed: file.text && showingLines > MAX_LINES_TO_BE_RENDERED,
       });
+    }
 
     Object.assign(state, {
       ...diffData,

spec/javascripts/diffs/store/mutations_spec.js

 import mutations from '~/diffs/store/mutations';
 import * as types from '~/diffs/store/mutation_types';
 import { INLINE_DIFF_VIEW_TYPE } from '~/diffs/constants';
+import diffFileMockData from '../mock_data/diff_file';
 
 describe('DiffsStoreMutations', () => {
   describe('SET_BASE_CONFIG', () => {
@@ -24,6 +25,23 @@ describe('DiffsStoreMutations', () => {
     });
   });
 
+  describe('SET_DIFF_DATA', () => {
+    it('should set diff data type properly', () => {
+      const state = {};
+      const diffMock = {
+        diff_files: [diffFileMockData],
+      };
+
+      mutations[types.SET_DIFF_DATA](state, diffMock);
+
+      const firstLine = state.diffFiles[0].parallelDiffLines[0];
+
+      expect(firstLine.right.text).toBeUndefined();
+      expect(state.diffFiles[0].renderIt).toEqual(true);
+      expect(state.diffFiles[0].collapsed).toEqual(false);
+    });
+  });
+
   describe('SET_DIFF_VIEW_TYPE', () => {
     it('should set diff view type properly', () => {
       const state = {};