CSSVariableData* CSSVariableResolver::valueForCustomProperty(AtomicString name)
{
if (m_variablesSeen.contains(name)) {
m_cycleStartPoints.add(name);
return nullptr;
}
if (!m_styleVariableData)
return nullptr;
CSSVariableData* variableData = m_styleVariableData->getVariable(name);
if (!variableData)
return nullptr;
if (!variableData->needsVariableResolution())
return variableData;
RefPtr<CSSVariableData> newVariableData = resolveCustomProperty(name, *variableData);
m_styleVariableData->setVariable(name, newVariableData);
return newVariableData.get();
}
PassRefPtr<CSSVariableData> CSSVariableResolver::resolveCustomProperty(AtomicString name, const CSSVariableData& variableData)
{
ASSERT(variableData.needsVariableResolution());
Vector<CSSParserToken> tokens;
m_variablesSeen.add(name);
bool success = resolveTokenRange(variableData.tokens(), tokens);
m_variablesSeen.remove(name);
// The old variable data holds onto the backing string the new resolved CSSVariableData
// relies on. Ensure it will live beyond us overwriting the RefPtr in StyleVariableData.
ASSERT(variableData.refCount() > 1);
if (!success || !m_cycleStartPoints.isEmpty()) {
m_cycleStartPoints.remove(name);
return nullptr;
}
return CSSVariableData::createResolved(tokens, variableData);
}