// Copyright 2017 The Bazel Authors. All rights reserved.
//
// Licensed 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
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package com.google.devtools.build.lib.profiler.callcounts;

import static com.google.common.truth.Truth.assertThat;

import com.google.common.collect.ImmutableList;
import com.google.perftools.profiles.ProfileProto.Function;
import com.google.perftools.profiles.ProfileProto.Location;
import com.google.perftools.profiles.ProfileProto.Profile;
import com.google.perftools.profiles.ProfileProto.Sample;
import java.util.ArrayList;
import java.util.List;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/** Tests for {@link Callcounts}. */
@RunWith(JUnit4.class)
public class CallcountsTest {
  /** Please leave these methods here as the profile lines are affected if you move them */
  private void callMethod1() {
    Callcounts.registerCall();
  }

  private void callMethod2() {
    Callcounts.registerCall();
  }

  @Test
  public void testCallCounts() {
    int samplePeriod = 1;
    int sampleVariance = 0;
    int maxCallstackDepth = 2;
    Callcounts.init(samplePeriod, sampleVariance, maxCallstackDepth);
    callMethod1();
    callMethod2();
    Profile profile = Callcounts.createProfile();
    assertThat(profile.getSampleList()).hasSize(2);
    List<String> callstack0 = sampleToCallstack(profile, profile.getSample(0));
    List<String> callstack1 = sampleToCallstack(profile, profile.getSample(1));
    String cls = getClass().getName();
    assertThat(ImmutableList.of(callstack0, callstack1))
        .containsExactly(
            ImmutableList.of(cls + ".callMethod1(35)", cls + ".testCallCounts(48)"),
            ImmutableList.of(cls + ".callMethod2(39)", cls + ".testCallCounts(49)"));
  }

  /** Formats a callstack as (method name)(line) */
  private List<String> sampleToCallstack(Profile profile, Sample sample) {
    List<String> result = new ArrayList<>();
    for (long locationId : sample.getLocationIdList()) {
      Location location = profile.getLocation((int) locationId - 1);
      assertThat(location.getLineList()).hasSize(1);
      long functionId = location.getLine(0).getFunctionId();
      long line = location.getLine(0).getLine();
      Function function = profile.getFunction((int) functionId - 1);
      long methodId = function.getName();
      String method = profile.getStringTable((int) methodId);
      result.add(String.format("%s(%d)", method, line));
    }
    return result;
  }
}