third_party/WebKit/Source/core/html/imports/HTMLImportStateResolver.cpp

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#include "core/html/imports/HTMLImportStateResolver.h"

#include "core/html/imports/HTMLImport.h"
#include "core/html/imports/HTMLImportChild.h"
#include "core/html/imports/HTMLImportLoader.h"

namespace blink {

inline bool HTMLImportStateResolver::isBlockingFollowers(HTMLImport* import)
{
    if (!import->isSync())
        return false;
    HTMLImportChild* child = toHTMLImportChild(import);
    if (!child->loader()->isFirstImport(child))
        return false;
    return !import->state().isReady();
}

inline bool HTMLImportStateResolver::shouldBlockScriptExecution() const
{
    // FIXME: Memoize to make this faster.
    for (HTMLImport* ancestor = m_import; ancestor; ancestor = ancestor->parent()) {
        for (HTMLImport* predecessor = ancestor->previous(); predecessor; predecessor = predecessor->previous()) {
            if (isBlockingFollowers(predecessor))
                return true;
        }
    }

    for (HTMLImport* child = m_import->firstChild(); child; child = child->next()) {
        if (isBlockingFollowers(child))
            return true;
    }

    return false;
}

inline bool HTMLImportStateResolver::isActive() const
{
    return !m_import->hasFinishedLoading();
}

HTMLImportState HTMLImportStateResolver::resolve() const
{
    if (shouldBlockScriptExecution())
        return HTMLImportState(HTMLImportState::BlockingScriptExecution);
    if (isActive())
        return HTMLImportState(HTMLImportState::Active);
    return HTMLImportState(HTMLImportState::Ready);
}

} // namespace blink