src/third_party/WebKit/Source/core/dom/shadow/SelectRuleFeatureSet.cpp

   1 /*
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   9  * notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  * copyright notice, this list of conditions and the following disclaimer
  12  * in the documentation and/or other materials provided with the
  13  * distribution.
  14  *     * Neither the name of Google Inc. nor the names of its
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  16  * this software without specific prior written permission.
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  19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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  30
  31 #include "config.h"
  32 #include "core/dom/shadow/SelectRuleFeatureSet.h"
  33
  34 #include "core/css/CSSSelector.h"
  35
  36 #include "wtf/BitVector.h"
  37
  38 namespace blink {
  39
  40 SelectRuleFeatureSet::SelectRuleFeatureSet()
  41     : m_featureFlags(0)
  42 {
  43 }
  44
  45 void SelectRuleFeatureSet::add(const SelectRuleFeatureSet& featureSet)
  46 {
  47     m_cssRuleFeatureSet.add(featureSet.m_cssRuleFeatureSet);
  48     m_featureFlags |= featureSet.m_featureFlags;
  49 }
  50
  51 void SelectRuleFeatureSet::clear()
  52 {
  53     m_cssRuleFeatureSet.clear();
  54     m_featureFlags = 0;
  55 }
  56
  57 void SelectRuleFeatureSet::collectFeaturesFromSelector(const CSSSelector& selector)
  58 {
  59     m_cssRuleFeatureSet.collectFeaturesFromSelector(selector);
  60
  61     switch (selector.pseudoType()) {
  62     case CSSSelector::PseudoChecked:
  63         setSelectRuleFeature(AffectedSelectorChecked);
  64         break;
  65     case CSSSelector::PseudoEnabled:
  66         setSelectRuleFeature(AffectedSelectorEnabled);
  67         break;
  68     case CSSSelector::PseudoDisabled:
  69         setSelectRuleFeature(AffectedSelectorDisabled);
  70         break;
  71     case CSSSelector::PseudoIndeterminate:
  72         setSelectRuleFeature(AffectedSelectorIndeterminate);
  73         break;
  74     case CSSSelector::PseudoLink:
  75         setSelectRuleFeature(AffectedSelectorLink);
  76         break;
  77     case CSSSelector::PseudoTarget:
  78         setSelectRuleFeature(AffectedSelectorTarget);
  79         break;
  80     case CSSSelector::PseudoVisited:
  81         setSelectRuleFeature(AffectedSelectorVisited);
  82         break;
  83     default:
  84         break;
  85     }
  86 }
  87
  88 bool SelectRuleFeatureSet::checkSelectorsForClassChange(const SpaceSplitString& changedClasses) const
  89 {
  90     unsigned changedSize = changedClasses.size();
  91     for (unsigned i = 0; i < changedSize; ++i) {
  92         if (hasSelectorForClass(changedClasses[i]))
  93             return true;
  94     }
  95     return false;
  96 }
  97
  98 bool SelectRuleFeatureSet::checkSelectorsForClassChange(const SpaceSplitString& oldClasses, const SpaceSplitString& newClasses) const
  99 {
 100     if (!oldClasses.size())
 101         return checkSelectorsForClassChange(newClasses);
 102
 103     // Class vectors tend to be very short. This is faster than using a hash table.
 104     BitVector remainingClassBits;
 105     remainingClassBits.ensureSize(oldClasses.size());
 106
 107     for (unsigned i = 0; i < newClasses.size(); ++i) {
 108         bool found = false;
 109         for (unsigned j = 0; j < oldClasses.size(); ++j) {
 110             if (newClasses[i] == oldClasses[j]) {
 111                 // Mark each class that is still in the newClasses so we can skip doing
 112                 // an n^2 search below when looking for removals. We can't break from
 113                 // this loop early since a class can appear more than once.
 114                 remainingClassBits.quickSet(j);
 115                 found = true;
 116             }
 117         }
 118         // Class was added.
 119         if (!found) {
 120             if (hasSelectorForClass(newClasses[i]))
 121                 return true;
 122         }
 123     }
 124
 125     for (unsigned i = 0; i < oldClasses.size(); ++i) {
 126         if (remainingClassBits.quickGet(i))
 127             continue;
 128
 129         // Class was removed.
 130         if (hasSelectorForClass(oldClasses[i]))
 131             return true;
 132     }
 133     return false;
 134 }
 135
 136 }
 137