Source/WebCore/layout/formattingContexts/inline/InlineFormattingQuirks.cpp

/*
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#include "config.h"
#include "InlineFormattingQuirks.h"

#if ENABLE(LAYOUT_FORMATTING_CONTEXT)

#include "InlineFormattingContext.h"
#include "LayoutBoxGeometry.h"

namespace WebCore {
namespace Layout {

InlineFormattingQuirks::InlineFormattingQuirks(const InlineFormattingContext& inlineFormattingContext)
    : FormattingQuirks(inlineFormattingContext)
{
}

InlineLayoutUnit InlineFormattingQuirks::initialLineHeight() const
{
    ASSERT(!layoutState().inStandardsMode());
    // Negative lineHeight value means the line-height is not set
    auto& rootStyle = formattingContext().root().style();
    return rootStyle.lineHeight().isNegative() ? rootStyle.fontMetrics().floatHeight() : rootStyle.computedLineHeight();
}

bool InlineFormattingQuirks::inlineLevelBoxAffectsLineBox(const InlineLevelBox& inlineLevelBox, const LineBox& lineBox) const
{
    ASSERT(!layoutState().inStandardsMode());
    if (inlineLevelBox.isLineBreakBox()) {
        // In quirks mode linebreak boxes (<br>) stop affecting the line box when (assume <br> is nested e.g. <span style="font-size: 100px"><br></span>)
        // 1. the root inline box has content <div>content<br>/div>
        // 2. there's at least one atomic inline level box on the line e.g <div><img><br></div> or <div><span><img></span><br></div>
        // 3. there's at least one inline box with content e.g. <div><span>content</span><br></div>
        if (lineBox.rootInlineBox().hasContent())
            return false;
        if (lineBox.hasAtomicInlineLevelBox())
            return false;
        // At this point we either have only the <br> on the line or inline boxes with or without content.
        auto& inlineLevelBoxes = lineBox.nonRootInlineLevelBoxes();
        ASSERT(!inlineLevelBoxes.isEmpty());
        if (inlineLevelBoxes.size() == 1)
            return true;
        for (auto& inlineLevelBox : lineBox.nonRootInlineLevelBoxes()) {
            // Filter out empty inline boxes e.g. <div><span></span><span></span><br></div>
            if (inlineLevelBox.isInlineBox() && inlineLevelBox.hasContent())
                return false;
        }
        return true;
    }
    if (inlineLevelBox.isInlineBox()) {
        // Inline boxes (e.g. root inline box or <span>) affects line boxes either through the strut or actual content.
        if (inlineLevelBox.hasContent())
            return true;
        if (inlineLevelBox.isRootInlineBox()) {
            // This root inline box has no direct text content and we are in non-standards mode.
            // Now according to legacy line layout, we need to apply the following list-item specific quirk:
            // We do not create markers for list items when the list-style-type is none, while other browsers do.
            // The side effect of having no marker is that in quirks mode we have to specifically check for list-item
            // and make sure it is treated as if it had content and stretched the line.
            // see LegacyInlineFlowBox c'tor.
            return inlineLevelBox.layoutBox().style().isOriginalDisplayListItemType();
        }
        // Non-root inline boxes (e.g. <span>).
        auto& boxGeometry = formattingContext().geometryForBox(inlineLevelBox.layoutBox());
        if (boxGeometry.horizontalBorder() || boxGeometry.horizontalPadding().value_or(0_lu)) {
            // Horizontal border and padding make the inline box stretch the line (e.g. <span style="padding: 10px;"></span>).
            return true;
        }
        return false;
    }
    ASSERT_NOT_REACHED();
    return false;
}

bool InlineFormattingQuirks::hasSoftWrapOpportunityAtImage() const
{
    ASSERT(layoutState().inQuirksMode());
    return !formattingContext().root().isTableCell();
}

}
}

#endif