Commit 4fc02f6f authored by Emilio Cobos Álvarez's avatar Emilio Cobos Álvarez
Browse files

Bug 1742411 - Prefer content property to img src on image elements. r=dholbert 

Given the compat reports in bug 1484928, I don't think it's worth
keeping the current behavior.

Our behavior should match other browsers now. Rather than making
content: url() work everywhere even for otherwise-replaced elements,
just special-case this since that's what other browsers seem to do.

Differential Revision: https://phabricator.services.mozilla.com/D131797
parent 08952898

layout/base/nsCSSFrameConstructor.cpp

+1 −14
Original line number Diff line number Diff line
@@ -1432,19 +1432,6 @@ static void MoveChildrenTo(nsIFrame* aOldParent, nsContainerFrame* aNewParent, 
  }

}



static bool ShouldCreateImageFrameForContent(const Element& aElement,

                                             ComputedStyle& aStyle) {

  if (aElement.IsRootOfNativeAnonymousSubtree()) {

    return false;

  }

  auto& content = aStyle.StyleContent()->mContent;

  if (!content.IsItems()) {

    return false;

  }

  Span<const StyleContentItem> items = content.AsItems().AsSpan();

  return items.Length() == 1 && items[0].IsImage();

}



//----------------------------------------------------------------------



nsCSSFrameConstructor::nsCSSFrameConstructor(Document* aDocument,
@@ -5341,7 +5328,7 @@ nsCSSFrameConstructor::FindElementData(const Element& aElement, 


  // Check for 'content: <image-url>' on the element (which makes us ignore

  // 'display' values other than 'none' or 'contents').

  if (ShouldCreateImageFrameForContent(aElement, aStyle)) {

  if (nsImageFrame::ShouldCreateImageFrameForContent(aElement, aStyle)) {

    static const FrameConstructionData sImgData =

        SIMPLE_FCDATA(NS_NewImageFrameForContentProperty);

    return &sImgData;

layout/generic/nsImageFrame.cpp

+19 −1
Original line number Diff line number Diff line
@@ -830,11 +830,29 @@ static bool HasAltText(const Element& aElement) { 
  return aElement.HasNonEmptyAttr(nsGkAtoms::alt);

}



bool nsImageFrame::ShouldCreateImageFrameForContent(

    const Element& aElement, const ComputedStyle& aStyle) {

  if (aElement.IsRootOfNativeAnonymousSubtree()) {

    return false;

  }

  const auto& content = aStyle.StyleContent()->mContent;

  if (!content.IsItems()) {

    return false;

  }

  Span<const StyleContentItem> items = content.AsItems().AsSpan();

  return items.Length() == 1 && items[0].IsImage();

}



// Check if we want to use an image frame or just let the frame constructor make

// us into an inline.

/* static */

bool nsImageFrame::ShouldCreateImageFrameFor(const Element& aElement,

                                             ComputedStyle& aStyle) {

                                             const ComputedStyle& aStyle) {

  if (ShouldCreateImageFrameForContent(aElement, aStyle)) {

    // Prefer the content property, for compat reasons, see bug 1484928.

    return false;

  }



  if (ImageOk(aElement.State())) {

    // Image is fine or loading; do the image frame thing

    return true;

layout/generic/nsImageFrame.h

+8 −1
Original line number Diff line number Diff line
@@ -133,13 +133,20 @@ class nsImageFrame : public nsAtomicContainerFrame, public nsIReflowCallback { 
  already_AddRefed<imgIRequest> GetCurrentRequest() const;

  void Notify(imgIRequest*, int32_t aType, const nsIntRect* aData);



  /**

   * Returns whether we should replace an element with an image corresponding to

   * its 'content' CSS property.

   */

  static bool ShouldCreateImageFrameForContent(const mozilla::dom::Element&,

                                               const ComputedStyle&);



  /**

   * Function to test whether given an element and its style, that element

   * should get an image frame.  Note that this method is only used by the

   * frame constructor; it's only here because it uses gIconLoad for now.

   */

  static bool ShouldCreateImageFrameFor(const mozilla::dom::Element&,

                                        ComputedStyle&);

                                        const ComputedStyle&);



  ImgDrawResult DisplayAltFeedback(gfxContext& aRenderingContext,

                                   const nsRect& aDirtyRect, nsPoint aPt,

testing/web-platform/meta/css/css-content/element-replacement-on-replaced-element.tentative.html.ini

0 → 100644
+2 −0
Original line number Diff line number Diff line 
[element-replacement-on-replaced-element.tentative.html]

  expected: FAIL

testing/web-platform/tests/css/css-content/element-replacement-image-no-src-ref.html

0 → 100644
+2 −0
Original line number Diff line number Diff line 
<!doctype html>

<img src="/images/yellow.png" width=100 height=100>