Honor the updateSynchronously parameter

spec/text-editor-component-spec.js

@@ -1,6 +1,7 @@
 const {it, fit, ffit, fffit, beforeEach, afterEach, conditionPromise, timeoutPromise} = require('./async-spec-helpers')
 
 const TextEditorComponent = require('../src/text-editor-component')
+const TextEditorElement = require('../src/text-editor-element')
 const TextEditor = require('../src/text-editor')
 const TextBuffer = require('text-buffer')
 const fs = require('fs')
@@ -2381,6 +2382,41 @@ describe('TextEditorComponent', () => {
     })
   })
 
+  describe('synchronous updates', () => {
+    let editorElementWasUpdatedSynchronously
+
+    beforeEach(() => {
+      editorElementWasUpdatedSynchronously = TextEditorElement.prototype.updatedSynchronously
+    })
+
+    afterEach(() => {
+      TextEditorElement.prototype.setUpdatedSynchronously(editorElementWasUpdatedSynchronously)
+    })
+
+    it('updates synchronously when updatedSynchronously is true', () => {
+      const editor = buildEditor()
+      const {element} = new TextEditorComponent({model: editor, updatedSynchronously: true})
+      jasmine.attachToDOM(element)
+
+      editor.setText('Lorem ipsum dolor')
+      expect(Array.from(element.querySelectorAll('.line:not(.dummy)')).map(l => l.textContent)).toEqual([
+        editor.lineTextForScreenRow(0)
+      ])
+    })
+
+    it('updates synchronously when creating a component via TextEditor and TextEditorElement.prototype.updatedSynchronously is true', () => {
+      TextEditorElement.prototype.setUpdatedSynchronously(true)
+      const editor = buildEditor()
+      const element = editor.element
+      jasmine.attachToDOM(element)
+
+      editor.setText('Lorem ipsum dolor')
+      expect(Array.from(element.querySelectorAll('.line:not(.dummy)')).map(l => l.textContent)).toEqual([
+        editor.lineTextForScreenRow(0)
+      ])
+    })
+  })
+
   describe('pixelPositionForScreenPositionSync(point)', () => {
     it('returns the pixel position for the given point, regardless of whether or not it is currently on screen', async () => {
       const {component, element, editor} = buildComponent({rowsPerTile: 2, autoHeight: false})

src/text-editor-component.js

@@ -64,6 +64,7 @@ class TextEditorComponent {
     this.refs = {}
 
     this.updateSync = this.updateSync.bind(this)
+    this.updatedSynchronously = this.props.updatedSynchronously
     this.didScrollDummyScrollbar = this.didScrollDummyScrollbar.bind(this)
     this.didMouseDownOnContent = this.didMouseDownOnContent.bind(this)
     this.disposables = new CompositeDisposable()

src/text-editor.coffee

@@ -13,6 +13,7 @@ Selection = require './selection'
 TextMateScopeSelector = require('first-mate').ScopeSelector
 GutterContainer = require './gutter-container'
 TextEditorComponent = null
+TextEditorElement = null
 {isDoubleWidthCharacter, isHalfWidthCharacter, isKoreanCharacter, isWrapBoundary} = require './text-utils'
 
 ZERO_WIDTH_NBSP = '\ufeff'
@@ -3581,7 +3582,11 @@ class TextEditor extends Model
       @component.element
     else
       TextEditorComponent ?= require('./text-editor-component')
-      new TextEditorComponent({model: this, styleManager: atom.styles})
+      TextEditorElement ?= require('./text-editor-element')
+      new TextEditorComponent({
+        model: this,
+        updatedSynchronously: TextEditorElement.prototype.updatedSynchronously
+      })
       @component.element
 
   # Essential: Retrieves the greyed out placeholder of a mini editor.