content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.alibaba.metrics;
  
  import org.junit.Test;
  
  import static org.assertj.core.api.Assertions.assertThat;
  
  public class RatioGaugeTest {
      @Test
      public void ratiosAreHumanReadable() throws Exception {
          final RatioGauge.Ratio ratio = RatioGauge.Ratio.of(100, 200);
  
          assertThat(ratio.toString())
                  .isEqualTo("100.0:200.0");
      }
  
      @Test
      public void calculatesTheRatioOfTheNumeratorToTheDenominator() throws Exception {
          final RatioGauge regular = new RatioGauge() {
              @Override
              protected Ratio getRatio() {
                  return RatioGauge.Ratio.of(2, 4);
              }
          };
  
          assertThat(regular.getValue())
                  .isEqualTo(0.5);
      }
  
      @Test
      public void handlesDivideByZeroIssues() throws Exception {
          final RatioGauge divByZero = new RatioGauge() {
              @Override
              protected Ratio getRatio() {
                  return Ratio.of(100, 0);
              }
          };
  
          assertThat(divByZero.getValue())
                  .isNaN();
      }
  
      @Test
      public void handlesInfiniteDenominators() throws Exception {
          final RatioGauge infinite = new RatioGauge() {
              @Override
              protected Ratio getRatio() {
                  return Ratio.of(10, Double.POSITIVE_INFINITY);
              }
          };
  
          assertThat(infinite.getValue())
                  .isNaN();
      }
  
      @Test
      public void handlesNaNDenominators() throws Exception {
          final RatioGauge nan = new RatioGauge() {
              @Override
              protected Ratio getRatio() {
                  return Ratio.of(10, Double.NaN);
              }
          };
  
          assertThat(nan.getValue())
                  .isNaN();
      }
  }
  