Source/core/dom/PseudoElement.cpp

/*
 * Copyright (C) 2012 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#include "config.h"
#include "core/dom/PseudoElement.h"

#include "core/inspector/InspectorInstrumentation.h"
#include "core/rendering/RenderObject.h"
#include "core/rendering/RenderQuote.h"
#include "core/rendering/style/ContentData.h"

namespace WebCore {

const QualifiedName& pseudoElementTagName()
{
    DEFINE_STATIC_LOCAL(QualifiedName, name, (nullAtom, "<pseudo>", nullAtom));
    return name;
}

String PseudoElement::pseudoElementNameForEvents(PseudoId pseudoId)
{
    DEFINE_STATIC_LOCAL(const String, after, ("::after"));
    DEFINE_STATIC_LOCAL(const String, before, ("::before"));
    switch (pseudoId) {
    case AFTER:
        return after;
    case BEFORE:
        return before;
    default:
        return emptyString();
    }
}

PseudoElement::PseudoElement(Element* parent, PseudoId pseudoId)
    : Element(pseudoElementTagName(), &parent->document(), CreatePseudoElement)
    , m_pseudoId(pseudoId)
{
    ASSERT(pseudoId != NOPSEUDO);
    setParentOrShadowHostNode(parent);
    setHasCustomStyleCallbacks();
}

PassRefPtr<RenderStyle> PseudoElement::customStyleForRenderer()
{
    return parentOrShadowHostElement()->renderer()->getCachedPseudoStyle(m_pseudoId);
}

void PseudoElement::dispose()
{
    InspectorInstrumentation::pseudoElementDestroyed(this);

    ASSERT(!nextSibling());
    ASSERT(!previousSibling());

    detach();
    RefPtr<Element> parent = parentOrShadowHostElement();
    setParentOrShadowHostNode(0);
    removedFrom(parent.get());
}

void PseudoElement::attach(const AttachContext& context)
{
    ASSERT(!renderer());

    Element::attach(context);

    RenderObject* renderer = this->renderer();
    if (!renderer)
        return;
    RenderStyle* style = renderer->style();
    if (style->hasFlowFrom())
        return;
    if (style->styleType() != BEFORE && style->styleType() != AFTER)
        return;
    ASSERT(style->contentData());

    for (const ContentData* content = style->contentData(); content; content = content->next()) {
        RenderObject* child = content->createRenderer(document(), style);
        if (renderer->isChildAllowed(child, style)) {
            renderer->addChild(child);
            if (child->isQuote())
                toRenderQuote(child)->attachQuote();
        } else
            child->destroy();
    }
}

bool PseudoElement::rendererIsNeeded(const RenderStyle& style)
{
    return pseudoElementRendererIsNeeded(&style);
}

void PseudoElement::didRecalcStyle(StyleRecalcChange)
{
    if (!renderer())
        return;

    // The renderers inside pseudo elements are anonymous so they don't get notified of recalcStyle and must have
    // the style propagated downward manually similar to RenderObject::propagateStyleToAnonymousChildren.
    RenderObject* renderer = this->renderer();
    for (RenderObject* child = renderer->nextInPreOrder(renderer); child; child = child->nextInPreOrder(renderer)) {
        // We only manage the style for the generated content items.
        if (!child->isText() && !child->isQuote() && !child->isImage())
            continue;

        // The style for the RenderTextFragment for first letter is managed by an enclosing block, not by us.
        if (child->style()->styleType() == FIRST_LETTER)
            continue;

        child->setPseudoStyle(renderer->style());
    }
}

} // namespace