Use NaN/Inf to represent unresolved/indefinite SMILTimes

Source/core/svg/animation/SMILTime.h

 /*
  * Copyright (C) 2008 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 16 matching lines @@
 #define SMILTime_h
 
 #include "wtf/Assertions.h"
 #include "wtf/MathExtras.h"
 
 namespace blink {
 
 class SMILTime {
 public:
     SMILTime() : m_time(0) { }
-    SMILTime(double time) : m_time(time) { ASSERT(!std::isnan(time)); }
-    SMILTime(const SMILTime& o) : m_time(o.m_time) { }
+    SMILTime(double time) : m_time(time) { }
 
-    static SMILTime unresolved() { return unresolvedValue; }
-    static SMILTime indefinite() { return indefiniteValue; }
+    static SMILTime unresolved() { return std::numeric_limits<double>::quiet_NaN(); }
+    static SMILTime indefinite() { return std::numeric_limits<double>::infinity(); }
 
-    SMILTime& operator=(const SMILTime& o) { m_time = o.m_time; return *this; }
     double value() const { return m_time; }
 
-    bool isFinite() const { return m_time < indefiniteValue; }
-    bool isIndefinite() const { return m_time == indefiniteValue; }
-    bool isUnresolved() const { return m_time == unresolvedValue; }
+    bool isFinite() const { return std::isfinite(m_time); }
+    bool isIndefinite() const { return std::isinf(m_time); }
+    bool isUnresolved() const { return std::isnan(m_time); }
 
 private:
-    static const double unresolvedValue;
-    static const double indefiniteValue;
-
     double m_time;
 };
 
 class SMILTimeWithOrigin {
 public:
     enum Origin {
         ParserOrigin,
         ScriptOrigin
     };
 
@@ skipping 17 matching lines @@
 };
 
 struct SMILInterval {
     SMILInterval() { }
     SMILInterval(const SMILTime& begin, const SMILTime& end) : begin(begin), end(end) { }
 
     SMILTime begin;
     SMILTime end;
 };
 
-inline bool operator==(const SMILTime& a, const SMILTime& b) { return a.isFinite() && a.value() == b.value(); }
+inline bool operator==(const SMILTime& a, const SMILTime& b) { return (a.isUnresolved() && b.isUnresolved()) || a.value() == b.value(); }
 inline bool operator!(const SMILTime& a) { return !a.isFinite() || !a.value(); }
 inline bool operator!=(const SMILTime& a, const SMILTime& b) { return !operator==(a, b); }
-inline bool operator>(const SMILTime& a, const SMILTime& b) { return a.value() > b.value(); }
-inline bool operator<(const SMILTime& a, const SMILTime& b) { return a.value() < b.value(); }
-inline bool operator>=(const SMILTime& a, const SMILTime& b) { return a.value() > b.value() || operator==(a, b); }
-inline bool operator<=(const SMILTime& a, const SMILTime& b) { return a.value() < b.value() || operator==(a, b); }
+inline bool operator>(const SMILTime& a, const SMILTime& b) { return a.isUnresolved() || (a.value() > b.value()); }
+inline bool operator<(const SMILTime& a, const SMILTime& b) { return operator>(b, a); }
+inline bool operator>=(const SMILTime& a, const SMILTime& b) { return operator>(a, b) || operator==(a, b); }
+inline bool operator<=(const SMILTime& a, const SMILTime& b) { return operator<(a, b) || operator==(a, b); }
 inline bool operator<(const SMILTimeWithOrigin& a, const SMILTimeWithOrigin& b) { return a.time() < b.time(); }
 
 SMILTime operator+(const SMILTime&, const SMILTime&);
 SMILTime operator-(const SMILTime&, const SMILTime&);
 // So multiplying times does not make too much sense but SMIL defines it for duration * repeatCount
 SMILTime operator*(const SMILTime&, const SMILTime&);
 
 inline bool operator!=(const SMILInterval& a, const SMILInterval& b)
 {
     // Compare the "raw" values since the operator!= for SMILTime always return
     // true for non-finite times.
     return a.begin.value() != b.begin.value() || a.end.value() != b.end.value();
 }
 
 }
 
 #endif // SMILTime_h