Bug 1340483 - Part 2. Expose chrome-only previewValue attribute. r=baku,heycam

MozReview-Commit-ID: BCu0vXVm6wj

dom/html/HTMLInputElement.cpp

@@ -2912,6 +2912,24 @@ HTMLInputElement::GetPreviewNode()
   return nullptr;
 }
 
+NS_IMETHODIMP_(void)
+HTMLInputElement::SetPreviewValue(const nsAString& aValue)
+{
+  nsTextEditorState* state = GetEditorState();
+  if (state) {
+    state->SetPreviewText(aValue, true);
+  }
+}
+
+NS_IMETHODIMP_(void)
+HTMLInputElement::GetPreviewValue(nsAString& aValue)
+{
+  nsTextEditorState* state = GetEditorState();
+  if (state) {
+    state->GetPreviewText(aValue);
+  }
+}
+
 void
 HTMLInputElement::GetDisplayFileName(nsAString& aValue) const
 {

dom/html/HTMLInputElement.h

@@ -237,6 +237,8 @@ public:
   NS_IMETHOD_(Element*) CreatePreviewNode() override;
   NS_IMETHOD_(Element*) GetPreviewNode() override;
   NS_IMETHOD_(void) UpdatePlaceholderVisibility(bool aNotify) override;
+  NS_IMETHOD_(void) SetPreviewValue(const nsAString& aValue) override;
+  NS_IMETHOD_(void) GetPreviewValue(nsAString& aValue) override;
   NS_IMETHOD_(bool) GetPlaceholderVisibility() override;
   NS_IMETHOD_(void) InitializeKeyboardEventListeners() override;
   NS_IMETHOD_(void) OnValueChanged(bool aNotify, bool aWasInteractiveUserChange) override;

dom/html/HTMLTextAreaElement.cpp

@@ -333,6 +333,17 @@ HTMLTextAreaElement::GetPreviewNode()
   return mState.GetPreviewNode();
 }
 
+NS_IMETHODIMP_(void)
+HTMLTextAreaElement::SetPreviewValue(const nsAString& aValue)
+{
+  mState.SetPreviewText(aValue, true);
+}
+
+NS_IMETHODIMP_(void)
+HTMLTextAreaElement::GetPreviewValue(nsAString& aValue)
+{
+  mState.GetPreviewText(aValue);
+}
 
 nsresult
 HTMLTextAreaElement::SetValueInternal(const nsAString& aValue,

dom/html/HTMLTextAreaElement.h

@@ -107,6 +107,8 @@ public:
   NS_IMETHOD_(Element*) GetPreviewNode() override;
   NS_IMETHOD_(void) UpdatePlaceholderVisibility(bool aNotify) override;
   NS_IMETHOD_(bool) GetPlaceholderVisibility() override;
+  NS_IMETHOD_(void) SetPreviewValue(const nsAString& aValue) override;
+  NS_IMETHOD_(void) GetPreviewValue(nsAString& aValue) override;
   NS_IMETHOD_(void) InitializeKeyboardEventListeners() override;
   NS_IMETHOD_(void) OnValueChanged(bool aNotify, bool aWasInteractiveUserChange) override;
   virtual void GetValueFromSetRangeText(nsAString& aValue) override;

dom/html/nsITextControlElement.h

@@ -164,6 +164,16 @@ public:
    */
   NS_IMETHOD_(mozilla::dom::Element*) GetPreviewNode() = 0;
 
+  /**
+   * Update preview value for the text control.
+   */
+  NS_IMETHOD_(void) SetPreviewValue(const nsAString& aValue) = 0;
+
+  /**
+   * Get the current preview value for text control.
+   */
+  NS_IMETHOD_(void) GetPreviewValue(nsAString& aValue) = 0;
+
   /**
    * Initialize the keyboard event listeners.
    */

dom/html/nsTextEditorState.cpp

@@ -2722,6 +2722,37 @@ nsTextEditorState::UpdatePlaceholderText(bool aNotify)
   mPlaceholderDiv->GetFirstChild()->SetText(placeholderValue, aNotify);
 }
 
+void
+nsTextEditorState::SetPreviewText(const nsAString& aValue, bool aNotify)
+{
+  MOZ_ASSERT(mPreviewDiv, "This function should not be called if "
+                            "mPreviewDiv isn't set");
+
+  // If we don't have a preview div, there's nothing to do.
+  if (!mPreviewDiv)
+    return;
+
+  nsAutoString previewValue(aValue);
+
+  nsContentUtils::RemoveNewlines(previewValue);
+  MOZ_ASSERT(mPreviewDiv->GetFirstChild(), "preview div has no child");
+  mPreviewDiv->GetFirstChild()->SetText(previewValue, aNotify);
+}
+
+void
+nsTextEditorState::GetPreviewText(nsAString& aValue)
+{
+  // If we don't have a preview div, there's nothing to do.
+  if (!mPreviewDiv)
+    return;
+
+  MOZ_ASSERT(mPreviewDiv->GetFirstChild(), "preview div has no child");
+  const nsTextFragment *text = mPreviewDiv->GetFirstChild()->GetText();
+
+  aValue.Truncate();
+  text->AppendTo(aValue);
+}
+
 void
 nsTextEditorState::UpdatePlaceholderVisibility(bool aNotify)
 {

dom/html/nsTextEditorState.h

@@ -223,8 +223,13 @@ public:
   bool GetPlaceholderVisibility() {
     return mPlaceholderVisibility;
   }
+
   void UpdatePlaceholderText(bool aNotify);
 
+  // preview methods
+  void SetPreviewText(const nsAString& aValue, bool aNotify);
+  void GetPreviewText(nsAString& aValue);
+
   /**
    * Get the maxlength attribute
    * @param aMaxLength the value of the max length attr

dom/webidl/HTMLInputElement.webidl

@@ -265,3 +265,8 @@ partial interface HTMLInputElement {
   [Pref="dom.forms.datetime", Func="IsChromeOrXBL"]
   void setFocusState(boolean aIsFocused);
 };
+
+partial interface HTMLInputElement {
+  [ChromeOnly]
+  attribute DOMString previewValue;
+};

dom/webidl/HTMLTextAreaElement.webidl

@@ -98,3 +98,8 @@ partial interface HTMLTextAreaElement {
   [ChromeOnly]
   void setUserInput(DOMString input);
 };
+
+partial interface HTMLTextAreaElement {
+  [ChromeOnly]
+  attribute DOMString previewValue;
+};