third_party/WebKit/Source/core/style/GridLength.h

/*
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#ifndef GridLength_h
#define GridLength_h

#include "platform/Length.h"
#include "wtf/Allocator.h"

namespace blink {

// This class wraps the <track-breadth> which can be either a <percentage>,
// <length>, min-content, max-content or <flex>. This class avoids spreading the
// knowledge of <flex> throughout the layout directory by adding an new unit to
// Length.h.
class GridLength {
  DISALLOW_NEW();

 public:
  GridLength(const Length& length)
      : m_length(length), m_flex(0), m_type(LengthType) {}

  explicit GridLength(double flex) : m_flex(flex), m_type(FlexType) {}

  bool isLength() const { return m_type == LengthType; }
  bool isFlex() const { return m_type == FlexType; }

  const Length& length() const {
    ASSERT(isLength());
    return m_length;
  }

  double flex() const {
    ASSERT(isFlex());
    return m_flex;
  }

  bool hasPercentage() const {
    return m_type == LengthType && m_length.isPercentOrCalc();
  }

  bool operator==(const GridLength& o) const {
    return m_length == o.m_length && m_flex == o.m_flex && m_type == o.m_type;
  }

  bool isContentSized() const {
    return m_type == LengthType &&
           (m_length.isAuto() || m_length.isMinContent() ||
            m_length.isMaxContent());
  }

 private:
  // Ideally we would put the 2 following fields in a union, but Length has a
  // constructor, a destructor and a copy assignment which isn't allowed.
  Length m_length;
  double m_flex;
  enum GridLengthType { LengthType, FlexType };
  GridLengthType m_type;
};

}  // namespace blink

#endif  // GridLength_h