1 files changed, 72 insertions, 0 deletions
diff --git a/chromium/third_party/blink/renderer/core/css/resolver/cascade_resolver.cc b/chromium/third_party/blink/renderer/core/css/resolver/cascade_resolver.cc
new file mode 100644
index 00000000000..55865460fa8
--- /dev/null
+++ b/chromium/third_party/blink/renderer/core/css/resolver/cascade_resolver.cc
@@ -0,0 +1,72 @@
+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "third_party/blink/renderer/core/css/resolver/cascade_resolver.h"
+
+#include "third_party/blink/renderer/core/animation/css/css_animations.h"
+#include "third_party/blink/renderer/core/css/css_variable_data.h"
+#include "third_party/blink/renderer/core/css/properties/css_property.h"
+#include "third_party/blink/renderer/core/css/resolver/cascade_priority.h"
+
+namespace blink {
+
+bool CascadeResolver::IsLocked(const CSSProperty& property) const {
+  return IsLocked(property.GetCSSPropertyName());
+}
+
+bool CascadeResolver::IsLocked(const CSSPropertyName& name) const {
+  return stack_.Contains(name);
+}
+
+bool CascadeResolver::AllowSubstitution(CSSVariableData* data) const {
+  if (data && data->IsAnimationTainted() && stack_.size()) {
+    const CSSPropertyName& name = stack_.back();
+    if (name.IsCustomProperty())
+      return true;
+    const CSSProperty& property = CSSProperty::Get(name.Id());
+    return !CSSAnimations::IsAnimationAffectingProperty(property);
+  }
+  return true;
+}
+
+void CascadeResolver::MarkUnapplied(CascadePriority* priority) const {
+  DCHECK(priority);
+  *priority = CascadePriority(*priority, 0);
+}
+
+void CascadeResolver::MarkApplied(CascadePriority* priority) const {
+  DCHECK(priority);
+  *priority = CascadePriority(*priority, generation_);
+}
+
+bool CascadeResolver::DetectCycle(const CSSProperty& property) {
+  wtf_size_t index = stack_.Find(property.GetCSSPropertyName());
+  if (index == kNotFound)
+    return false;
+  cycle_depth_ = std::min(cycle_depth_, index);
+  return true;
+}
+
+bool CascadeResolver::InCycle() const {
+  return cycle_depth_ != kNotFound;
+}
+
+CascadeResolver::AutoLock::AutoLock(const CSSProperty& property,
+                                    CascadeResolver& resolver)
+    : AutoLock(property.GetCSSPropertyName(), resolver) {}
+
+CascadeResolver::AutoLock::AutoLock(const CSSPropertyName& name,
+                                    CascadeResolver& resolver)
+    : resolver_(resolver) {
+  DCHECK(!resolver.IsLocked(name));
+  resolver_.stack_.push_back(name);
+}
+
+CascadeResolver::AutoLock::~AutoLock() {
+  resolver_.stack_.pop_back();
+  if (resolver_.stack_.size() <= resolver_.cycle_depth_)
+    resolver_.cycle_depth_ = kNotFound;
+}
+
+}  // namespace blink