Merge pull request #3606 from atom/bo-model-placeholder-text

Model EditorView::setPlaceholderText

spec/editor-component-spec.coffee

@@ -2225,7 +2225,7 @@ describe "EditorComponent", ->
 
   describe "when placholderText is specified", ->
     it "renders the placeholder text when the buffer is empty", ->
-      component.setProps(placeholderText: 'Hello World')
+      editor.setPlaceholderText('Hello World')
       expect(componentNode.querySelector('.placeholder-text')).toBeNull()
       editor.setText('')
       nextAnimationFrame()

spec/editor-spec.coffee

@@ -3665,3 +3665,21 @@ describe "Editor", ->
       editor.selectPageUp()
       expect(editor.getScrollTop()).toBe 0
       expect(editor.getSelectedBufferRanges()).toEqual [[[0,0], [12,2]]]
+
+  describe '.get/setPlaceholderText()', ->
+    it 'can be created with placeholderText', ->
+      TextBuffer = require 'text-buffer'
+      newEditor = new Editor
+        buffer: new TextBuffer
+        mini: true
+        placeholderText: 'yep'
+      expect(newEditor.getPlaceholderText()).toBe 'yep'
+
+    it 'models placeholderText and emits an event when changed', ->
+      editor.onDidChangePlaceholderText handler = jasmine.createSpy()
+
+      expect(editor.getPlaceholderText()).toBeUndefined()
+
+      editor.setPlaceholderText('OK')
+      expect(handler).toHaveBeenCalledWith 'OK'
+      expect(editor.getPlaceholderText()).toBe 'OK'

src/editor-component.coffee

@@ -64,7 +64,7 @@ EditorComponent = React.createClass
       decorations = editor.decorationsForScreenRowRange(renderedStartRow, renderedEndRow)
       highlightDecorations = @getHighlightDecorations(decorations)
       lineDecorations = @getLineDecorations(decorations)
-      placeholderText = @props.placeholderText if @props.placeholderText? and editor.isEmpty()
+      placeholderText = editor.getPlaceholderText() if editor.isEmpty()
       visible = @isVisible()
 
       scrollHeight = editor.getScrollHeight()
@@ -358,6 +358,7 @@ EditorComponent = React.createClass
     @subscribe editor.observeDecorations(@onDecorationAdded)
     @subscribe editor.onDidRemoveDecoration(@onDecorationRemoved)
     @subscribe editor.onDidChangeCharacterWidths(@onCharacterWidthsChanged)
+    @subscribe editor.onDidChangePlaceholderText(@onPlaceholderTextChanged)
     @subscribe editor.$scrollTop.changes, @onScrollTopChanged
     @subscribe editor.$scrollLeft.changes, @requestUpdate
     @subscribe editor.$verticalScrollbarWidth.changes, @requestUpdate
@@ -780,6 +781,9 @@ EditorComponent = React.createClass
   onCharacterWidthsChanged: (@scopedCharacterWidthsChangeCount) ->
     @requestUpdate()
 
+  onPlaceholderTextChanged: ->
+    @requestUpdate()
+
   handleDragUntilMouseUp: (event, dragHandler) ->
     {editor} = @props
     dragging = false

src/editor-view.coffee

@@ -85,13 +85,13 @@ class EditorView extends View
       {@editor, mini, placeholderText} = editorOrParams
       props ?= {}
       props.mini = mini
-      props.placeholderText = placeholderText
       @editor ?= new Editor
         buffer: new TextBuffer
         softWrapped: false
         tabLength: 2
         softTabs: true
         mini: mini
+        placeholderText: placeholderText
 
     props = defaults({@editor, parentView: this}, props)
     @component = React.renderComponent(EditorComponent(props), @element)
@@ -346,16 +346,9 @@ class EditorView extends View
   redraw: ->
     deprecate('Please remove from your code. ::redraw no longer does anything')
 
-  # Public: Set the text to appear in the editor when it is empty.
-  #
-  # This only affects mini editors.
-  #
-  # * `placeholderText` A {String} of text to display when empty.
   setPlaceholderText: (placeholderText) ->
-    if @component?
-      @component.setProps({placeholderText})
-    else
-      @props.placeholderText = placeholderText
+    deprecate('Use TextEditor::setPlaceholderText instead. eg. editorView.getModel().setPlaceholderText(text)')
+    @getModel().setPlaceholderText(placeholderText)
 
   lineElementForScreenRow: (screenRow) ->
     $(@component.lineNodeForScreenRow(screenRow))

src/editor.coffee

@@ -77,7 +77,7 @@ class Editor extends Model
     '$verticalScrollbarWidth', '$horizontalScrollbarHeight', '$scrollTop', '$scrollLeft',
     'manageScrollPosition', toProperty: 'displayBuffer'
 
-  constructor: ({@softTabs, initialLine, initialColumn, tabLength, softWrapped, @displayBuffer, buffer, registerEditor, suppressCursorCreation, @mini}) ->
+  constructor: ({@softTabs, initialLine, initialColumn, tabLength, softWrapped, @displayBuffer, buffer, registerEditor, suppressCursorCreation, @mini, @placeholderText}) ->
     super
 
     @emitter = new Emitter
@@ -405,6 +405,15 @@ class Editor extends Model
   onDidRemoveDecoration: (callback) ->
     @displayBuffer.onDidRemoveDecoration(callback)
 
+  # Extended: Calls your `callback` when the placeholder text is changed.
+  #
+  # * `callback` {Function}
+  #   * `placeholderText` {String} new text
+  #
+  # Returns a {Disposable} on which `.dispose()` can be called to unsubscribe.
+  onDidChangePlaceholderText: (callback) ->
+    @emitter.on 'did-change-placeholder-text', callback
+
   onDidChangeCharacterWidths: (callback) ->
     @displayBuffer.onDidChangeCharacterWidths(callback)
 
@@ -2670,6 +2679,21 @@ class Editor extends Model
   Section: Editor Rendering
   ###
 
+  # Public: Retrieves the greyed out placeholder of a mini editor.
+  #
+  # Returns a {String}.
+  getPlaceholderText: ->
+    @placeholderText
+
+  # Public: Set the greyed out placeholder of a mini editor. Placeholder text
+  # will be displayed when the editor has no content.
+  #
+  # * `placeholderText` {String} text that is displayed when the editor has no content.
+  setPlaceholderText: (placeholderText) ->
+    return if @placeholderText is placeholderText
+    @placeholderText = placeholderText
+    @emitter.emit 'did-change-placeholder-text', @placeholderText
+
   # Extended: Retrieves the number of the row that is visible and currently at the
   # top of the editor.
   #