chromium/src/third_party/blink/renderer/platform/animation/timing_function_test.cc - manifest_repos/chromium_src - Git at Google

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 #include "third_party/blink/renderer/platform/animation/timing_function.h"

 #include <sstream>
 #include <string>
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/blink/renderer/platform/testing/runtime_enabled_features_test_helpers.h"
 #include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"

 namespace blink {

 namespace {

 class TimingFunctionTest : public testing::Test {
  public:
   TimingFunctionTest() {}

   void NotEqualHelperLoop(
       Vector<std::pair<std::string, scoped_refptr<TimingFunction>>>& v) {
     for (size_t i = 0; i < v.size(); ++i) {
       for (size_t j = 0; j < v.size(); ++j) {
         if (i == j)
           continue;
         EXPECT_NE(v[i], v[j])
             << v[i].first << " (" << v[i].second->ToString() << ")"
             << " ==  " << v[j].first << " (" << v[j].second->ToString() << ")"
             << "\n";
       }
     }
   }
 };

 TEST_F(TimingFunctionTest, LinearToString) {
   scoped_refptr<TimingFunction> linear_timing = LinearTimingFunction::Shared();
   EXPECT_EQ(linear_timing->ToString(), "linear");
 }

 TEST_F(TimingFunctionTest, CubicToString) {
   scoped_refptr<TimingFunction> cubic_ease_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE);
   EXPECT_EQ("ease", cubic_ease_timing->ToString());
   scoped_refptr<TimingFunction> cubic_ease_in_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN);
   EXPECT_EQ("ease-in", cubic_ease_in_timing->ToString());
   scoped_refptr<TimingFunction> cubic_ease_out_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_OUT);
   EXPECT_EQ("ease-out", cubic_ease_out_timing->ToString());
   scoped_refptr<TimingFunction> cubic_ease_in_out_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN_OUT);
   EXPECT_EQ("ease-in-out", cubic_ease_in_out_timing->ToString());

   scoped_refptr<TimingFunction> cubic_custom_timing =
       CubicBezierTimingFunction::Create(0.17, 0.67, 1, -1.73);
   EXPECT_EQ("cubic-bezier(0.17, 0.67, 1, -1.73)",
             cubic_custom_timing->ToString());
 }

 TEST_F(TimingFunctionTest, StepToString) {
   scoped_refptr<TimingFunction> step_timing_start =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
   EXPECT_EQ("steps(1, start)", step_timing_start->ToString());

   scoped_refptr<TimingFunction> step_timing_end =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::END);
   EXPECT_EQ("steps(1)", step_timing_end->ToString());

   scoped_refptr<TimingFunction> step_timing_custom_start =
       StepsTimingFunction::Create(3, StepsTimingFunction::StepPosition::START);
   EXPECT_EQ("steps(3, start)", step_timing_custom_start->ToString());

   scoped_refptr<TimingFunction> step_timing_custom_end =
       StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::END);
   EXPECT_EQ("steps(5)", step_timing_custom_end->ToString());
 }

 TEST_F(TimingFunctionTest, BaseOperatorEq) {
   scoped_refptr<TimingFunction> linear_timing = LinearTimingFunction::Shared();
   scoped_refptr<TimingFunction> cubic_timing1 =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN);
   scoped_refptr<TimingFunction> cubic_timing2 =
       CubicBezierTimingFunction::Create(0.17, 0.67, 1, -1.73);
   scoped_refptr<TimingFunction> steps_timing1 =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::END);
   scoped_refptr<TimingFunction> steps_timing2 =
       StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::START);

   Vector<std::pair<std::string, scoped_refptr<TimingFunction>>> v;
   v.push_back(std::make_pair("linearTiming", linear_timing));
   v.push_back(std::make_pair("cubicTiming1", cubic_timing1));
   v.push_back(std::make_pair("cubicTiming2", cubic_timing2));
   v.push_back(std::make_pair("stepsTiming1", steps_timing1));
   v.push_back(std::make_pair("stepsTiming2", steps_timing2));
   NotEqualHelperLoop(v);
 }

 TEST_F(TimingFunctionTest, LinearOperatorEq) {
   scoped_refptr<TimingFunction> linear_timing1 = LinearTimingFunction::Shared();
   scoped_refptr<TimingFunction> linear_timing2 = LinearTimingFunction::Shared();
   EXPECT_EQ(*linear_timing1, *linear_timing1);
   EXPECT_EQ(*linear_timing1, *linear_timing2);
 }

 TEST_F(TimingFunctionTest, CubicOperatorEq) {
   scoped_refptr<TimingFunction> cubic_ease_in_timing1 =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN);
   scoped_refptr<TimingFunction> cubic_ease_in_timing2 =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN);
   EXPECT_EQ(*cubic_ease_in_timing1, *cubic_ease_in_timing1);
   EXPECT_EQ(*cubic_ease_in_timing1, *cubic_ease_in_timing2);

   scoped_refptr<TimingFunction> cubic_ease_out_timing1 =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_OUT);
   scoped_refptr<TimingFunction> cubic_ease_out_timing2 =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_OUT);
   EXPECT_EQ(*cubic_ease_out_timing1, *cubic_ease_out_timing1);
   EXPECT_EQ(*cubic_ease_out_timing1, *cubic_ease_out_timing2);

   scoped_refptr<TimingFunction> cubic_ease_in_out_timing1 =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN_OUT);
   scoped_refptr<TimingFunction> cubic_ease_in_out_timing2 =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN_OUT);
   EXPECT_EQ(*cubic_ease_in_out_timing1, *cubic_ease_in_out_timing1);
   EXPECT_EQ(*cubic_ease_in_out_timing1, *cubic_ease_in_out_timing2);

   scoped_refptr<TimingFunction> cubic_custom_timing1 =
       CubicBezierTimingFunction::Create(0.17, 0.67, 1, -1.73);
   scoped_refptr<TimingFunction> cubic_custom_timing2 =
       CubicBezierTimingFunction::Create(0.17, 0.67, 1, -1.73);
   EXPECT_EQ(*cubic_custom_timing1, *cubic_custom_timing1);
   EXPECT_EQ(*cubic_custom_timing1, *cubic_custom_timing2);

   Vector<std::pair<std::string, scoped_refptr<TimingFunction>>> v;
   v.push_back(std::make_pair("cubicEaseInTiming1", cubic_ease_in_timing1));
   v.push_back(std::make_pair("cubicEaseOutTiming1", cubic_ease_out_timing1));
   v.push_back(
       std::make_pair("cubicEaseInOutTiming1", cubic_ease_in_out_timing1));
   v.push_back(std::make_pair("cubicCustomTiming1", cubic_custom_timing1));
   NotEqualHelperLoop(v);
 }

 TEST_F(TimingFunctionTest, CubicOperatorEqReflectivity) {
   scoped_refptr<TimingFunction> cubic_a = CubicBezierTimingFunction::Preset(
       CubicBezierTimingFunction::EaseType::EASE_IN);
   scoped_refptr<TimingFunction> cubic_b =
       CubicBezierTimingFunction::Create(0.42, 0.0, 1.0, 1.0);
   EXPECT_NE(*cubic_a, *cubic_b);
   EXPECT_NE(*cubic_b, *cubic_a);
 }

 TEST_F(TimingFunctionTest, StepsOperatorEq) {
   scoped_refptr<TimingFunction> steps_timing_start1 =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
   scoped_refptr<TimingFunction> steps_timing_start2 =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
   EXPECT_EQ(*steps_timing_start1, *steps_timing_start1);
   EXPECT_EQ(*steps_timing_start1, *steps_timing_start2);

   scoped_refptr<TimingFunction> steps_timing_end1 =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::END);
   scoped_refptr<TimingFunction> steps_timing_end2 =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::END);
   EXPECT_EQ(*steps_timing_end1, *steps_timing_end1);
   EXPECT_EQ(*steps_timing_end1, *steps_timing_end2);

   scoped_refptr<TimingFunction> steps_timing_custom1 =
       StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::START);
   scoped_refptr<TimingFunction> steps_timing_custom2 =
       StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::END);
   scoped_refptr<TimingFunction> steps_timing_custom3 =
       StepsTimingFunction::Create(7, StepsTimingFunction::StepPosition::START);
   scoped_refptr<TimingFunction> steps_timing_custom4 =
       StepsTimingFunction::Create(7, StepsTimingFunction::StepPosition::END);

   EXPECT_EQ(
       *StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::START),
       *steps_timing_custom1);
   EXPECT_EQ(
       *StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::END),
       *steps_timing_custom2);
   EXPECT_EQ(
       *StepsTimingFunction::Create(7, StepsTimingFunction::StepPosition::START),
       *steps_timing_custom3);
   EXPECT_EQ(
       *StepsTimingFunction::Create(7, StepsTimingFunction::StepPosition::END),
       *steps_timing_custom4);

   Vector<std::pair<std::string, scoped_refptr<TimingFunction>>> v;
   v.push_back(std::make_pair("stepsTimingStart1", steps_timing_start1));
   v.push_back(std::make_pair("stepsTimingEnd1", steps_timing_end1));
   v.push_back(std::make_pair("stepsTimingCustom1", steps_timing_custom1));
   v.push_back(std::make_pair("stepsTimingCustom2", steps_timing_custom2));
   v.push_back(std::make_pair("stepsTimingCustom3", steps_timing_custom3));
   v.push_back(std::make_pair("stepsTimingCustom4", steps_timing_custom4));
   NotEqualHelperLoop(v);
 }

 TEST_F(TimingFunctionTest, StepsOperatorEqPreset) {
   scoped_refptr<TimingFunction> steps_a =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
   scoped_refptr<TimingFunction> steps_b =
       StepsTimingFunction::Create(1, StepsTimingFunction::StepPosition::START);
   EXPECT_EQ(*steps_a, *steps_b);
   EXPECT_EQ(*steps_b, *steps_a);
 }

 TEST_F(TimingFunctionTest, LinearEvaluate) {
   scoped_refptr<TimingFunction> linear_timing = LinearTimingFunction::Shared();
   EXPECT_EQ(0.2, linear_timing->Evaluate(0.2));
   EXPECT_EQ(0.6, linear_timing->Evaluate(0.6));
   EXPECT_EQ(-0.2, linear_timing->Evaluate(-0.2));
   EXPECT_EQ(1.6, linear_timing->Evaluate(1.6));
 }

 TEST_F(TimingFunctionTest, LinearRange) {
   double start = 0;
   double end = 1;
   scoped_refptr<TimingFunction> linear_timing = LinearTimingFunction::Shared();
   linear_timing->Range(&start, &end);
   EXPECT_NEAR(0, start, 0.01);
   EXPECT_NEAR(1, end, 0.01);
   start = -1;
   end = 10;
   linear_timing->Range(&start, &end);
   EXPECT_NEAR(-1, start, 0.01);
   EXPECT_NEAR(10, end, 0.01);
 }

 TEST_F(TimingFunctionTest, StepRange) {
   double start = 0;
   double end = 1;
   scoped_refptr<TimingFunction> steps =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
   steps->Range(&start, &end);
   EXPECT_NEAR(0, start, 0.01);
   EXPECT_NEAR(1, end, 0.01);

   start = -1;
   end = 10;
   steps->Range(&start, &end);
   EXPECT_NEAR(0, start, 0.01);
   EXPECT_NEAR(1, end, 0.01);
 }

 TEST_F(TimingFunctionTest, CubicRange) {
   double start = 0;
   double end = 1;

   scoped_refptr<TimingFunction> cubic_ease_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE);
   start = 0;
   end = 1;
   cubic_ease_timing->Range(&start, &end);
   EXPECT_NEAR(0, start, 0.01);
   EXPECT_NEAR(1, end, 0.01);
   start = -1;
   end = 10;
   cubic_ease_timing->Range(&start, &end);
   EXPECT_NEAR(-0.4, start, 0.01);
   EXPECT_NEAR(1, end, 0.01);

   scoped_refptr<TimingFunction> cubic_ease_in_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN);
   start = 0;
   end = 1;
   cubic_ease_in_timing->Range(&start, &end);
   EXPECT_NEAR(0, start, 0.01);
   EXPECT_NEAR(1, end, 0.01);
   start = -1;
   end = 10;
   cubic_ease_in_timing->Range(&start, &end);
   EXPECT_NEAR(0.0, start, 0.01);
   EXPECT_NEAR(16.51, end, 0.01);

   scoped_refptr<TimingFunction> cubic_ease_out_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_OUT);
   start = 0;
   end = 1;
   cubic_ease_out_timing->Range(&start, &end);
   EXPECT_NEAR(0, start, 0.01);
   EXPECT_NEAR(1, end, 0.01);
   start = -1;
   end = 10;
   cubic_ease_out_timing->Range(&start, &end);
   EXPECT_NEAR(-1.72, start, 0.01);
   EXPECT_NEAR(1.0, end, 0.01);

   scoped_refptr<TimingFunction> cubic_ease_in_out_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN_OUT);
   start = 0;
   end = 1;
   cubic_ease_in_out_timing->Range(&start, &end);
   EXPECT_NEAR(0, start, 0.01);
   EXPECT_NEAR(1, end, 0.01);
   start = -1;
   end = 10;
   cubic_ease_in_out_timing->Range(&start, &end);
   EXPECT_NEAR(0.0, start, 0.01);
   EXPECT_NEAR(1.0, end, 0.01);

   scoped_refptr<TimingFunction> cubic_custom_timing =
       CubicBezierTimingFunction::Create(0.17, 0.67, 1.0, -1.73);
   start = 0;
   end = 1;
   cubic_custom_timing->Range(&start, &end);
   EXPECT_NEAR(-0.33, start, 0.01);
   EXPECT_NEAR(1.0, end, 0.01);

   start = -1;
   end = 10;
   cubic_custom_timing->Range(&start, &end);
   EXPECT_NEAR(-3.94, start, 0.01);
   EXPECT_NEAR(1.0, end, 0.01);
 }

 TEST_F(TimingFunctionTest, CubicEvaluate) {
   double tolerance = 0.01;
   scoped_refptr<TimingFunction> cubic_ease_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE);
   EXPECT_NEAR(0.409, cubic_ease_timing->Evaluate(0.25), tolerance);
   EXPECT_NEAR(0.802, cubic_ease_timing->Evaluate(0.50), tolerance);
   EXPECT_NEAR(0.960, cubic_ease_timing->Evaluate(0.75), tolerance);

   scoped_refptr<TimingFunction> cubic_ease_in_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN);
   EXPECT_NEAR(0.093, cubic_ease_in_timing->Evaluate(0.25), tolerance);
   EXPECT_NEAR(0.315, cubic_ease_in_timing->Evaluate(0.50), tolerance);
   EXPECT_NEAR(0.622, cubic_ease_in_timing->Evaluate(0.75), tolerance);

   scoped_refptr<TimingFunction> cubic_ease_out_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_OUT);
   EXPECT_NEAR(0.378, cubic_ease_out_timing->Evaluate(0.25), tolerance);
   EXPECT_NEAR(0.685, cubic_ease_out_timing->Evaluate(0.50), tolerance);
   EXPECT_NEAR(0.907, cubic_ease_out_timing->Evaluate(0.75), tolerance);

   scoped_refptr<TimingFunction> cubic_ease_in_out_timing =
       CubicBezierTimingFunction::Preset(
           CubicBezierTimingFunction::EaseType::EASE_IN_OUT);
   EXPECT_NEAR(0.129, cubic_ease_in_out_timing->Evaluate(0.25), tolerance);
   EXPECT_NEAR(0.500, cubic_ease_in_out_timing->Evaluate(0.50), tolerance);
   EXPECT_NEAR(0.871, cubic_ease_in_out_timing->Evaluate(0.75), tolerance);

   scoped_refptr<TimingFunction> cubic_custom_timing =
       CubicBezierTimingFunction::Create(0.17, 0.67, 1, -1.73);
   EXPECT_NEAR(0.034, cubic_custom_timing->Evaluate(0.25), tolerance);
   EXPECT_NEAR(-0.217, cubic_custom_timing->Evaluate(0.50), tolerance);
   EXPECT_NEAR(-0.335, cubic_custom_timing->Evaluate(0.75), tolerance);
 }

 TEST_F(TimingFunctionTest, StepsEvaluate) {
   TimingFunction::LimitDirection left = TimingFunction::LimitDirection::LEFT;
   TimingFunction::LimitDirection right = TimingFunction::LimitDirection::RIGHT;

   scoped_refptr<TimingFunction> steps_timing_start =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
   EXPECT_EQ(-1.00, steps_timing_start->Evaluate(-1.10, right));
   EXPECT_EQ(0.00, steps_timing_start->Evaluate(-0.10, right));
   EXPECT_EQ(0.00, steps_timing_start->Evaluate(0.00, left));
   EXPECT_EQ(1.00, steps_timing_start->Evaluate(0.00, right));
   EXPECT_EQ(1.00, steps_timing_start->Evaluate(0.20, right));
   EXPECT_EQ(1.00, steps_timing_start->Evaluate(0.60, right));
   EXPECT_EQ(1.00, steps_timing_start->Evaluate(1.00, left));
   EXPECT_EQ(1.00, steps_timing_start->Evaluate(1.00, right));
   EXPECT_EQ(2.00, steps_timing_start->Evaluate(2.00, left));
   EXPECT_EQ(3.00, steps_timing_start->Evaluate(2.00, right));

   scoped_refptr<TimingFunction> steps_timing_end =
       StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::END);
   EXPECT_EQ(-2.00, steps_timing_end->Evaluate(-2.00, right));
   EXPECT_EQ(0.00, steps_timing_end->Evaluate(0.00, left));
   EXPECT_EQ(0.00, steps_timing_end->Evaluate(0.00, right));
   EXPECT_EQ(0.00, steps_timing_end->Evaluate(0.20, right));
   EXPECT_EQ(0.00, steps_timing_end->Evaluate(0.60, right));
   EXPECT_EQ(0.00, steps_timing_end->Evaluate(1.00, left));
   EXPECT_EQ(1.00, steps_timing_end->Evaluate(1.00, right));
   EXPECT_EQ(2.00, steps_timing_end->Evaluate(2.00, right));

   scoped_refptr<TimingFunction> steps_timing_custom_start =
       StepsTimingFunction::Create(4, StepsTimingFunction::StepPosition::START);
   EXPECT_EQ(-0.50, steps_timing_custom_start->Evaluate(-0.50, left));
   EXPECT_EQ(-0.25, steps_timing_custom_start->Evaluate(-0.50, right));
   EXPECT_EQ(0.00, steps_timing_custom_start->Evaluate(0.00, left));
   EXPECT_EQ(0.25, steps_timing_custom_start->Evaluate(0.00, right));
   EXPECT_EQ(0.25, steps_timing_custom_start->Evaluate(0.24, right));
   EXPECT_EQ(0.25, steps_timing_custom_start->Evaluate(0.25, left));
   EXPECT_EQ(0.50, steps_timing_custom_start->Evaluate(0.25, right));
   EXPECT_EQ(0.50, steps_timing_custom_start->Evaluate(0.49, right));
   EXPECT_EQ(0.50, steps_timing_custom_start->Evaluate(0.50, left));
   EXPECT_EQ(0.75, steps_timing_custom_start->Evaluate(0.50, right));
   EXPECT_EQ(0.75, steps_timing_custom_start->Evaluate(0.74, right));
   EXPECT_EQ(0.75, steps_timing_custom_start->Evaluate(0.75, left));
   EXPECT_EQ(1.00, steps_timing_custom_start->Evaluate(0.75, right));
   EXPECT_EQ(1.00, steps_timing_custom_start->Evaluate(1.00, left));
   EXPECT_EQ(1.00, steps_timing_custom_start->Evaluate(1.00, right));
   EXPECT_EQ(1.75, steps_timing_custom_start->Evaluate(1.50, right));

   scoped_refptr<TimingFunction> steps_timing_custom_end =
       StepsTimingFunction::Create(4, StepsTimingFunction::StepPosition::END);
   EXPECT_EQ(-2.25, steps_timing_custom_end->Evaluate(-2.00, left));
   EXPECT_EQ(-2.00, steps_timing_custom_end->Evaluate(-2.00, right));
   EXPECT_EQ(0.00, steps_timing_custom_end->Evaluate(0.00, left));
   EXPECT_EQ(0.00, steps_timing_custom_end->Evaluate(0.00, right));
   EXPECT_EQ(0.00, steps_timing_custom_end->Evaluate(0.24, right));
   EXPECT_EQ(0.00, steps_timing_custom_end->Evaluate(0.25, left));
   EXPECT_EQ(0.25, steps_timing_custom_end->Evaluate(0.25, right));
   EXPECT_EQ(0.25, steps_timing_custom_end->Evaluate(0.49, right));
   EXPECT_EQ(0.25, steps_timing_custom_end->Evaluate(0.50, left));
   EXPECT_EQ(0.50, steps_timing_custom_end->Evaluate(0.50, right));
   EXPECT_EQ(0.50, steps_timing_custom_end->Evaluate(0.74, right));
   EXPECT_EQ(0.50, steps_timing_custom_end->Evaluate(0.75, left));
   EXPECT_EQ(0.75, steps_timing_custom_end->Evaluate(0.75, right));
   EXPECT_EQ(0.75, steps_timing_custom_end->Evaluate(0.99, right));
   EXPECT_EQ(0.75, steps_timing_custom_end->Evaluate(1.00, left));
   EXPECT_EQ(1.00, steps_timing_custom_end->Evaluate(1.00, right));
   EXPECT_EQ(1.75, steps_timing_custom_end->Evaluate(2.00, left));
   EXPECT_EQ(2.00, steps_timing_custom_end->Evaluate(2.00, right));
 }

 }  // namespace

 }  // namespace blink
	/*
	* Copyright (c) 2013, Google 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:
	*
	* * Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* * Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following disclaimer
	* in the documentation and/or other materials provided with the
	* distribution.
	* * Neither the name of Google Inc. nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "third_party/blink/renderer/platform/animation/timing_function.h"

	#include <sstream>
	#include <string>
	#include "testing/gmock/include/gmock/gmock.h"
	#include "testing/gtest/include/gtest/gtest.h"
	#include "third_party/blink/renderer/platform/testing/runtime_enabled_features_test_helpers.h"
	#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"

	namespace blink {

	namespace {

	class TimingFunctionTest : public testing::Test {
	public:
	TimingFunctionTest() {}

	void NotEqualHelperLoop(
	Vector<std::pair<std::string, scoped_refptr<TimingFunction>>>& v) {
	for (size_t i = 0; i < v.size(); ++i) {
	for (size_t j = 0; j < v.size(); ++j) {
	if (i == j)
	continue;
	EXPECT_NE(v[i], v[j])
	<< v[i].first << " (" << v[i].second->ToString() << ")"
	<< " == " << v[j].first << " (" << v[j].second->ToString() << ")"
	<< "\n";
	}
	}
	}
	};

	TEST_F(TimingFunctionTest, LinearToString) {
	scoped_refptr<TimingFunction> linear_timing = LinearTimingFunction::Shared();
	EXPECT_EQ(linear_timing->ToString(), "linear");
	}

	TEST_F(TimingFunctionTest, CubicToString) {
	scoped_refptr<TimingFunction> cubic_ease_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE);
	EXPECT_EQ("ease", cubic_ease_timing->ToString());
	scoped_refptr<TimingFunction> cubic_ease_in_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN);
	EXPECT_EQ("ease-in", cubic_ease_in_timing->ToString());
	scoped_refptr<TimingFunction> cubic_ease_out_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_OUT);
	EXPECT_EQ("ease-out", cubic_ease_out_timing->ToString());
	scoped_refptr<TimingFunction> cubic_ease_in_out_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN_OUT);
	EXPECT_EQ("ease-in-out", cubic_ease_in_out_timing->ToString());

	scoped_refptr<TimingFunction> cubic_custom_timing =
	CubicBezierTimingFunction::Create(0.17, 0.67, 1, -1.73);
	EXPECT_EQ("cubic-bezier(0.17, 0.67, 1, -1.73)",
	cubic_custom_timing->ToString());
	}

	TEST_F(TimingFunctionTest, StepToString) {
	scoped_refptr<TimingFunction> step_timing_start =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
	EXPECT_EQ("steps(1, start)", step_timing_start->ToString());

	scoped_refptr<TimingFunction> step_timing_end =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::END);
	EXPECT_EQ("steps(1)", step_timing_end->ToString());

	scoped_refptr<TimingFunction> step_timing_custom_start =
	StepsTimingFunction::Create(3, StepsTimingFunction::StepPosition::START);
	EXPECT_EQ("steps(3, start)", step_timing_custom_start->ToString());

	scoped_refptr<TimingFunction> step_timing_custom_end =
	StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::END);
	EXPECT_EQ("steps(5)", step_timing_custom_end->ToString());
	}

	TEST_F(TimingFunctionTest, BaseOperatorEq) {
	scoped_refptr<TimingFunction> linear_timing = LinearTimingFunction::Shared();
	scoped_refptr<TimingFunction> cubic_timing1 =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN);
	scoped_refptr<TimingFunction> cubic_timing2 =
	CubicBezierTimingFunction::Create(0.17, 0.67, 1, -1.73);
	scoped_refptr<TimingFunction> steps_timing1 =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::END);
	scoped_refptr<TimingFunction> steps_timing2 =
	StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::START);

	Vector<std::pair<std::string, scoped_refptr<TimingFunction>>> v;
	v.push_back(std::make_pair("linearTiming", linear_timing));
	v.push_back(std::make_pair("cubicTiming1", cubic_timing1));
	v.push_back(std::make_pair("cubicTiming2", cubic_timing2));
	v.push_back(std::make_pair("stepsTiming1", steps_timing1));
	v.push_back(std::make_pair("stepsTiming2", steps_timing2));
	NotEqualHelperLoop(v);
	}

	TEST_F(TimingFunctionTest, LinearOperatorEq) {
	scoped_refptr<TimingFunction> linear_timing1 = LinearTimingFunction::Shared();
	scoped_refptr<TimingFunction> linear_timing2 = LinearTimingFunction::Shared();
	EXPECT_EQ(linear_timing1, linear_timing1);
	EXPECT_EQ(linear_timing1, linear_timing2);
	}

	TEST_F(TimingFunctionTest, CubicOperatorEq) {
	scoped_refptr<TimingFunction> cubic_ease_in_timing1 =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN);
	scoped_refptr<TimingFunction> cubic_ease_in_timing2 =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN);
	EXPECT_EQ(cubic_ease_in_timing1, cubic_ease_in_timing1);
	EXPECT_EQ(cubic_ease_in_timing1, cubic_ease_in_timing2);

	scoped_refptr<TimingFunction> cubic_ease_out_timing1 =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_OUT);
	scoped_refptr<TimingFunction> cubic_ease_out_timing2 =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_OUT);
	EXPECT_EQ(cubic_ease_out_timing1, cubic_ease_out_timing1);
	EXPECT_EQ(cubic_ease_out_timing1, cubic_ease_out_timing2);

	scoped_refptr<TimingFunction> cubic_ease_in_out_timing1 =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN_OUT);
	scoped_refptr<TimingFunction> cubic_ease_in_out_timing2 =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN_OUT);
	EXPECT_EQ(cubic_ease_in_out_timing1, cubic_ease_in_out_timing1);
	EXPECT_EQ(cubic_ease_in_out_timing1, cubic_ease_in_out_timing2);

	scoped_refptr<TimingFunction> cubic_custom_timing1 =
	CubicBezierTimingFunction::Create(0.17, 0.67, 1, -1.73);
	scoped_refptr<TimingFunction> cubic_custom_timing2 =
	CubicBezierTimingFunction::Create(0.17, 0.67, 1, -1.73);
	EXPECT_EQ(cubic_custom_timing1, cubic_custom_timing1);
	EXPECT_EQ(cubic_custom_timing1, cubic_custom_timing2);

	Vector<std::pair<std::string, scoped_refptr<TimingFunction>>> v;
	v.push_back(std::make_pair("cubicEaseInTiming1", cubic_ease_in_timing1));
	v.push_back(std::make_pair("cubicEaseOutTiming1", cubic_ease_out_timing1));
	v.push_back(
	std::make_pair("cubicEaseInOutTiming1", cubic_ease_in_out_timing1));
	v.push_back(std::make_pair("cubicCustomTiming1", cubic_custom_timing1));
	NotEqualHelperLoop(v);
	}

	TEST_F(TimingFunctionTest, CubicOperatorEqReflectivity) {
	scoped_refptr<TimingFunction> cubic_a = CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN);
	scoped_refptr<TimingFunction> cubic_b =
	CubicBezierTimingFunction::Create(0.42, 0.0, 1.0, 1.0);
	EXPECT_NE(cubic_a, cubic_b);
	EXPECT_NE(cubic_b, cubic_a);
	}

	TEST_F(TimingFunctionTest, StepsOperatorEq) {
	scoped_refptr<TimingFunction> steps_timing_start1 =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
	scoped_refptr<TimingFunction> steps_timing_start2 =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
	EXPECT_EQ(steps_timing_start1, steps_timing_start1);
	EXPECT_EQ(steps_timing_start1, steps_timing_start2);

	scoped_refptr<TimingFunction> steps_timing_end1 =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::END);
	scoped_refptr<TimingFunction> steps_timing_end2 =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::END);
	EXPECT_EQ(steps_timing_end1, steps_timing_end1);
	EXPECT_EQ(steps_timing_end1, steps_timing_end2);

	scoped_refptr<TimingFunction> steps_timing_custom1 =
	StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::START);
	scoped_refptr<TimingFunction> steps_timing_custom2 =
	StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::END);
	scoped_refptr<TimingFunction> steps_timing_custom3 =
	StepsTimingFunction::Create(7, StepsTimingFunction::StepPosition::START);
	scoped_refptr<TimingFunction> steps_timing_custom4 =
	StepsTimingFunction::Create(7, StepsTimingFunction::StepPosition::END);

	EXPECT_EQ(
	*StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::START),
	*steps_timing_custom1);
	EXPECT_EQ(
	*StepsTimingFunction::Create(5, StepsTimingFunction::StepPosition::END),
	*steps_timing_custom2);
	EXPECT_EQ(
	*StepsTimingFunction::Create(7, StepsTimingFunction::StepPosition::START),
	*steps_timing_custom3);
	EXPECT_EQ(
	*StepsTimingFunction::Create(7, StepsTimingFunction::StepPosition::END),
	*steps_timing_custom4);

	Vector<std::pair<std::string, scoped_refptr<TimingFunction>>> v;
	v.push_back(std::make_pair("stepsTimingStart1", steps_timing_start1));
	v.push_back(std::make_pair("stepsTimingEnd1", steps_timing_end1));
	v.push_back(std::make_pair("stepsTimingCustom1", steps_timing_custom1));
	v.push_back(std::make_pair("stepsTimingCustom2", steps_timing_custom2));
	v.push_back(std::make_pair("stepsTimingCustom3", steps_timing_custom3));
	v.push_back(std::make_pair("stepsTimingCustom4", steps_timing_custom4));
	NotEqualHelperLoop(v);
	}

	TEST_F(TimingFunctionTest, StepsOperatorEqPreset) {
	scoped_refptr<TimingFunction> steps_a =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
	scoped_refptr<TimingFunction> steps_b =
	StepsTimingFunction::Create(1, StepsTimingFunction::StepPosition::START);
	EXPECT_EQ(steps_a, steps_b);
	EXPECT_EQ(steps_b, steps_a);
	}

	TEST_F(TimingFunctionTest, LinearEvaluate) {
	scoped_refptr<TimingFunction> linear_timing = LinearTimingFunction::Shared();
	EXPECT_EQ(0.2, linear_timing->Evaluate(0.2));
	EXPECT_EQ(0.6, linear_timing->Evaluate(0.6));
	EXPECT_EQ(-0.2, linear_timing->Evaluate(-0.2));
	EXPECT_EQ(1.6, linear_timing->Evaluate(1.6));
	}

	TEST_F(TimingFunctionTest, LinearRange) {
	double start = 0;
	double end = 1;
	scoped_refptr<TimingFunction> linear_timing = LinearTimingFunction::Shared();
	linear_timing->Range(&start, &end);
	EXPECT_NEAR(0, start, 0.01);
	EXPECT_NEAR(1, end, 0.01);
	start = -1;
	end = 10;
	linear_timing->Range(&start, &end);
	EXPECT_NEAR(-1, start, 0.01);
	EXPECT_NEAR(10, end, 0.01);
	}

	TEST_F(TimingFunctionTest, StepRange) {
	double start = 0;
	double end = 1;
	scoped_refptr<TimingFunction> steps =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
	steps->Range(&start, &end);
	EXPECT_NEAR(0, start, 0.01);
	EXPECT_NEAR(1, end, 0.01);

	start = -1;
	end = 10;
	steps->Range(&start, &end);
	EXPECT_NEAR(0, start, 0.01);
	EXPECT_NEAR(1, end, 0.01);
	}

	TEST_F(TimingFunctionTest, CubicRange) {
	double start = 0;
	double end = 1;

	scoped_refptr<TimingFunction> cubic_ease_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE);
	start = 0;
	end = 1;
	cubic_ease_timing->Range(&start, &end);
	EXPECT_NEAR(0, start, 0.01);
	EXPECT_NEAR(1, end, 0.01);
	start = -1;
	end = 10;
	cubic_ease_timing->Range(&start, &end);
	EXPECT_NEAR(-0.4, start, 0.01);
	EXPECT_NEAR(1, end, 0.01);

	scoped_refptr<TimingFunction> cubic_ease_in_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN);
	start = 0;
	end = 1;
	cubic_ease_in_timing->Range(&start, &end);
	EXPECT_NEAR(0, start, 0.01);
	EXPECT_NEAR(1, end, 0.01);
	start = -1;
	end = 10;
	cubic_ease_in_timing->Range(&start, &end);
	EXPECT_NEAR(0.0, start, 0.01);
	EXPECT_NEAR(16.51, end, 0.01);

	scoped_refptr<TimingFunction> cubic_ease_out_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_OUT);
	start = 0;
	end = 1;
	cubic_ease_out_timing->Range(&start, &end);
	EXPECT_NEAR(0, start, 0.01);
	EXPECT_NEAR(1, end, 0.01);
	start = -1;
	end = 10;
	cubic_ease_out_timing->Range(&start, &end);
	EXPECT_NEAR(-1.72, start, 0.01);
	EXPECT_NEAR(1.0, end, 0.01);

	scoped_refptr<TimingFunction> cubic_ease_in_out_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN_OUT);
	start = 0;
	end = 1;
	cubic_ease_in_out_timing->Range(&start, &end);
	EXPECT_NEAR(0, start, 0.01);
	EXPECT_NEAR(1, end, 0.01);
	start = -1;
	end = 10;
	cubic_ease_in_out_timing->Range(&start, &end);
	EXPECT_NEAR(0.0, start, 0.01);
	EXPECT_NEAR(1.0, end, 0.01);

	scoped_refptr<TimingFunction> cubic_custom_timing =
	CubicBezierTimingFunction::Create(0.17, 0.67, 1.0, -1.73);
	start = 0;
	end = 1;
	cubic_custom_timing->Range(&start, &end);
	EXPECT_NEAR(-0.33, start, 0.01);
	EXPECT_NEAR(1.0, end, 0.01);

	start = -1;
	end = 10;
	cubic_custom_timing->Range(&start, &end);
	EXPECT_NEAR(-3.94, start, 0.01);
	EXPECT_NEAR(1.0, end, 0.01);
	}

	TEST_F(TimingFunctionTest, CubicEvaluate) {
	double tolerance = 0.01;
	scoped_refptr<TimingFunction> cubic_ease_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE);
	EXPECT_NEAR(0.409, cubic_ease_timing->Evaluate(0.25), tolerance);
	EXPECT_NEAR(0.802, cubic_ease_timing->Evaluate(0.50), tolerance);
	EXPECT_NEAR(0.960, cubic_ease_timing->Evaluate(0.75), tolerance);

	scoped_refptr<TimingFunction> cubic_ease_in_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN);
	EXPECT_NEAR(0.093, cubic_ease_in_timing->Evaluate(0.25), tolerance);
	EXPECT_NEAR(0.315, cubic_ease_in_timing->Evaluate(0.50), tolerance);
	EXPECT_NEAR(0.622, cubic_ease_in_timing->Evaluate(0.75), tolerance);

	scoped_refptr<TimingFunction> cubic_ease_out_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_OUT);
	EXPECT_NEAR(0.378, cubic_ease_out_timing->Evaluate(0.25), tolerance);
	EXPECT_NEAR(0.685, cubic_ease_out_timing->Evaluate(0.50), tolerance);
	EXPECT_NEAR(0.907, cubic_ease_out_timing->Evaluate(0.75), tolerance);

	scoped_refptr<TimingFunction> cubic_ease_in_out_timing =
	CubicBezierTimingFunction::Preset(
	CubicBezierTimingFunction::EaseType::EASE_IN_OUT);
	EXPECT_NEAR(0.129, cubic_ease_in_out_timing->Evaluate(0.25), tolerance);
	EXPECT_NEAR(0.500, cubic_ease_in_out_timing->Evaluate(0.50), tolerance);
	EXPECT_NEAR(0.871, cubic_ease_in_out_timing->Evaluate(0.75), tolerance);

	scoped_refptr<TimingFunction> cubic_custom_timing =
	CubicBezierTimingFunction::Create(0.17, 0.67, 1, -1.73);
	EXPECT_NEAR(0.034, cubic_custom_timing->Evaluate(0.25), tolerance);
	EXPECT_NEAR(-0.217, cubic_custom_timing->Evaluate(0.50), tolerance);
	EXPECT_NEAR(-0.335, cubic_custom_timing->Evaluate(0.75), tolerance);
	}

	TEST_F(TimingFunctionTest, StepsEvaluate) {
	TimingFunction::LimitDirection left = TimingFunction::LimitDirection::LEFT;
	TimingFunction::LimitDirection right = TimingFunction::LimitDirection::RIGHT;

	scoped_refptr<TimingFunction> steps_timing_start =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::START);
	EXPECT_EQ(-1.00, steps_timing_start->Evaluate(-1.10, right));
	EXPECT_EQ(0.00, steps_timing_start->Evaluate(-0.10, right));
	EXPECT_EQ(0.00, steps_timing_start->Evaluate(0.00, left));
	EXPECT_EQ(1.00, steps_timing_start->Evaluate(0.00, right));
	EXPECT_EQ(1.00, steps_timing_start->Evaluate(0.20, right));
	EXPECT_EQ(1.00, steps_timing_start->Evaluate(0.60, right));
	EXPECT_EQ(1.00, steps_timing_start->Evaluate(1.00, left));
	EXPECT_EQ(1.00, steps_timing_start->Evaluate(1.00, right));
	EXPECT_EQ(2.00, steps_timing_start->Evaluate(2.00, left));
	EXPECT_EQ(3.00, steps_timing_start->Evaluate(2.00, right));

	scoped_refptr<TimingFunction> steps_timing_end =
	StepsTimingFunction::Preset(StepsTimingFunction::StepPosition::END);
	EXPECT_EQ(-2.00, steps_timing_end->Evaluate(-2.00, right));
	EXPECT_EQ(0.00, steps_timing_end->Evaluate(0.00, left));
	EXPECT_EQ(0.00, steps_timing_end->Evaluate(0.00, right));
	EXPECT_EQ(0.00, steps_timing_end->Evaluate(0.20, right));
	EXPECT_EQ(0.00, steps_timing_end->Evaluate(0.60, right));
	EXPECT_EQ(0.00, steps_timing_end->Evaluate(1.00, left));
	EXPECT_EQ(1.00, steps_timing_end->Evaluate(1.00, right));
	EXPECT_EQ(2.00, steps_timing_end->Evaluate(2.00, right));

	scoped_refptr<TimingFunction> steps_timing_custom_start =
	StepsTimingFunction::Create(4, StepsTimingFunction::StepPosition::START);
	EXPECT_EQ(-0.50, steps_timing_custom_start->Evaluate(-0.50, left));
	EXPECT_EQ(-0.25, steps_timing_custom_start->Evaluate(-0.50, right));
	EXPECT_EQ(0.00, steps_timing_custom_start->Evaluate(0.00, left));
	EXPECT_EQ(0.25, steps_timing_custom_start->Evaluate(0.00, right));
	EXPECT_EQ(0.25, steps_timing_custom_start->Evaluate(0.24, right));
	EXPECT_EQ(0.25, steps_timing_custom_start->Evaluate(0.25, left));
	EXPECT_EQ(0.50, steps_timing_custom_start->Evaluate(0.25, right));
	EXPECT_EQ(0.50, steps_timing_custom_start->Evaluate(0.49, right));
	EXPECT_EQ(0.50, steps_timing_custom_start->Evaluate(0.50, left));
	EXPECT_EQ(0.75, steps_timing_custom_start->Evaluate(0.50, right));
	EXPECT_EQ(0.75, steps_timing_custom_start->Evaluate(0.74, right));
	EXPECT_EQ(0.75, steps_timing_custom_start->Evaluate(0.75, left));
	EXPECT_EQ(1.00, steps_timing_custom_start->Evaluate(0.75, right));
	EXPECT_EQ(1.00, steps_timing_custom_start->Evaluate(1.00, left));
	EXPECT_EQ(1.00, steps_timing_custom_start->Evaluate(1.00, right));
	EXPECT_EQ(1.75, steps_timing_custom_start->Evaluate(1.50, right));

	scoped_refptr<TimingFunction> steps_timing_custom_end =
	StepsTimingFunction::Create(4, StepsTimingFunction::StepPosition::END);
	EXPECT_EQ(-2.25, steps_timing_custom_end->Evaluate(-2.00, left));
	EXPECT_EQ(-2.00, steps_timing_custom_end->Evaluate(-2.00, right));
	EXPECT_EQ(0.00, steps_timing_custom_end->Evaluate(0.00, left));
	EXPECT_EQ(0.00, steps_timing_custom_end->Evaluate(0.00, right));
	EXPECT_EQ(0.00, steps_timing_custom_end->Evaluate(0.24, right));
	EXPECT_EQ(0.00, steps_timing_custom_end->Evaluate(0.25, left));
	EXPECT_EQ(0.25, steps_timing_custom_end->Evaluate(0.25, right));
	EXPECT_EQ(0.25, steps_timing_custom_end->Evaluate(0.49, right));
	EXPECT_EQ(0.25, steps_timing_custom_end->Evaluate(0.50, left));
	EXPECT_EQ(0.50, steps_timing_custom_end->Evaluate(0.50, right));
	EXPECT_EQ(0.50, steps_timing_custom_end->Evaluate(0.74, right));
	EXPECT_EQ(0.50, steps_timing_custom_end->Evaluate(0.75, left));
	EXPECT_EQ(0.75, steps_timing_custom_end->Evaluate(0.75, right));
	EXPECT_EQ(0.75, steps_timing_custom_end->Evaluate(0.99, right));
	EXPECT_EQ(0.75, steps_timing_custom_end->Evaluate(1.00, left));
	EXPECT_EQ(1.00, steps_timing_custom_end->Evaluate(1.00, right));
	EXPECT_EQ(1.75, steps_timing_custom_end->Evaluate(2.00, left));
	EXPECT_EQ(2.00, steps_timing_custom_end->Evaluate(2.00, right));
	}

	} // namespace

	} // namespace blink