/* vim:set ts=2 sw=2 sts=0 et: */
/* Any copyright is dedicated to the Public Domain.
 * http://creativecommons.org/publicdomain/zero/1.0/
 */

#include "gtest/gtest.h"
#include "js/Conversions.h"
#include "nsITelemetry.h"
#include "Telemetry.h"
#include "TelemetryFixture.h"
#include "TelemetryTestHelpers.h"

using namespace mozilla;
using namespace TelemetryTestHelpers;

TEST_F(TelemetryTestFixture, AccumulateCountHistogram)
{
  const uint32_t kExpectedValue = 100;
  AutoJSContextWithGlobal cx(mCleanGlobal);

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry, NS_LITERAL_CSTRING("TELEMETRY_TEST_COUNT"),
                       false);

  // Accumulate in the histogram
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_COUNT, kExpectedValue);

  // Get a snapshot for all the histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_COUNT", &snapshot, false);

  // Get the histogram from the snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_COUNT", snapshot, &histogram);

  // Get "sum" property from histogram
  JS::RootedValue sum(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "sum", histogram,  &sum);

  // Check that the "sum" stored in the histogram matches with |kExpectedValue|
  uint32_t uSum = 0;
  JS::ToUint32(cx.GetJSContext(), sum, &uSum);
  ASSERT_EQ(uSum, kExpectedValue) << "The histogram is not returning expected value";
}

TEST_F(TelemetryTestFixture, AccumulateKeyedCountHistogram)
{
  const uint32_t kExpectedValue = 100;
  AutoJSContextWithGlobal cx(mCleanGlobal);

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry,
                       NS_LITERAL_CSTRING("TELEMETRY_TEST_KEYED_COUNT"), true);

  // Accumulate data in the provided key within the histogram
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_KEYED_COUNT, NS_LITERAL_CSTRING("sample"),
                        kExpectedValue);

  // Get a snapshot for all the histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_KEYED_COUNT", &snapshot, true);

  // Get the histogram from the snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_KEYED_COUNT", snapshot, &histogram);

  // Get "sample" property from histogram
  JS::RootedValue expectedKeyData(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "sample", histogram,  &expectedKeyData);

  // Get "sum" property from keyed data
  JS::RootedValue sum(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "sum", expectedKeyData,  &sum);

  // Check that the sum stored in the histogram matches with |kExpectedValue|
  uint32_t uSum = 0;
  JS::ToUint32(cx.GetJSContext(), sum, &uSum);
  ASSERT_EQ(uSum, kExpectedValue) << "The histogram is not returning expected sum";
}

TEST_F(TelemetryTestFixture, TestKeyedKeysHistogram)
{
  AutoJSContextWithGlobal cx(mCleanGlobal);

  JS::RootedValue testHistogram(cx.GetJSContext());
  JS::RootedValue rval(cx.GetJSContext());

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry,
                       NS_LITERAL_CSTRING("TELEMETRY_TEST_KEYED_KEYS"), true);

  // Test the accumulation on both the allowed and unallowed keys, using
  // the API that accepts histogram IDs.
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_KEYED_KEYS, NS_LITERAL_CSTRING("not-allowed"), 1);
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_KEYED_KEYS, NS_LITERAL_CSTRING("testkey"), 0);
  // Do the same, using the API that accepts the histogram name as a string.
  Telemetry::Accumulate("TELEMETRY_TEST_KEYED_KEYS", NS_LITERAL_CSTRING("not-allowed"), 1);
  Telemetry::Accumulate("TELEMETRY_TEST_KEYED_KEYS", NS_LITERAL_CSTRING("CommonKey"), 1);

  // Get a snapshot for all the histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_KEYED_KEYS", &snapshot, true);

  // Get the histogram from the snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_KEYED_KEYS", snapshot, &histogram);

  // Get "testkey" property from histogram and check that it stores the correct
  // data.
  JS::RootedValue expectedKeyData(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "testkey", histogram,  &expectedKeyData);
  ASSERT_TRUE(!expectedKeyData.isUndefined())
    << "Cannot find the expected key in the histogram data";
  JS::RootedValue sum(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "sum", expectedKeyData,  &sum);
  uint32_t uSum = 0;
  JS::ToUint32(cx.GetJSContext(), sum, &uSum);
  ASSERT_EQ(uSum, 0U) << "The histogram is not returning expected sum for 'testkey'";

  // Do the same for the "CommonKey" property.
  GetProperty(cx.GetJSContext(), "CommonKey", histogram,  &expectedKeyData);
  ASSERT_TRUE(!expectedKeyData.isUndefined())
    << "Cannot find the expected key in the histogram data";
  GetProperty(cx.GetJSContext(), "sum", expectedKeyData,  &sum);
  JS::ToUint32(cx.GetJSContext(), sum, &uSum);
  ASSERT_EQ(uSum, 1U) << "The histogram is not returning expected sum for 'CommonKey'";

  GetProperty(cx.GetJSContext(), "not-allowed", histogram,  &expectedKeyData);
  ASSERT_TRUE(expectedKeyData.isUndefined())
    << "Unallowed keys must not be recorded in the histogram data";

  // The 'not-allowed' key accumulation for 'TELEMETRY_TESTED_KEYED_KEYS' was
  // attemtped twice, so we expect the count of
  // 'telemetry.accumulate_unknown_histogram_keys' to be 2
  const uint32_t expectedAccumulateUnknownCount = 2;
  JS::RootedValue scalarsSnapshot(cx.GetJSContext());
  GetScalarsSnapshot(true, cx.GetJSContext(),&scalarsSnapshot);
  CheckKeyedUintScalar("telemetry.accumulate_unknown_histogram_keys",
                       "TELEMETRY_TEST_KEYED_KEYS", cx.GetJSContext(),
                       scalarsSnapshot, expectedAccumulateUnknownCount);
}

TEST_F(TelemetryTestFixture, AccumulateCategoricalHistogram)
{
  const uint32_t kExpectedValue = 2;

  AutoJSContextWithGlobal cx(mCleanGlobal);

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry,
                       NS_LITERAL_CSTRING("TELEMETRY_TEST_CATEGORICAL"), false);

  // Accumulate one unit into the categorical histogram with label
  // Telemetry::LABELS_TELEMETRY_TEST_CATEGORICAL::CommonLabel
  Telemetry::AccumulateCategorical(Telemetry::LABELS_TELEMETRY_TEST_CATEGORICAL::CommonLabel);

  // Accumulate another unit into the same categorical histogram using a string label
  Telemetry::AccumulateCategorical(Telemetry::TELEMETRY_TEST_CATEGORICAL,
                                   NS_LITERAL_CSTRING("CommonLabel"));

  // Get a snapshot for all the histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_CATEGORICAL", &snapshot, false);

  // Get our histogram from the snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_CATEGORICAL", snapshot, &histogram);

  // Get counts array from histogram. Each entry in the array maps to a label in the histogram.
  JS::RootedValue counts(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "counts", histogram,  &counts);

  // Get the value for the label we care about
  JS::RootedValue value(cx.GetJSContext());
  GetElement(cx.GetJSContext(),
             static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_CATEGORICAL::CommonLabel),
             counts, &value);

  // Check that the value stored in the histogram matches with |kExpectedValue|
  uint32_t uValue = 0;
  JS::ToUint32(cx.GetJSContext(), value, &uValue);
  ASSERT_EQ(uValue, kExpectedValue) << "The histogram is not returning expected value";
}

TEST_F(TelemetryTestFixture, AccumulateKeyedCategoricalHistogram)
{
  const uint32_t kSampleExpectedValue = 2;
  const uint32_t kOtherSampleExpectedValue = 1;

  AutoJSContextWithGlobal cx(mCleanGlobal);

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry,
                       NS_LITERAL_CSTRING("TELEMETRY_TEST_KEYED_CATEGORICAL"), true);

  // Accumulate one unit into the categorical histogram with label
  // Telemetry::LABELS_TELEMETRY_TEST_KEYED_CATEGORICAL::CommonLabel
  Telemetry::AccumulateCategoricalKeyed(NS_LITERAL_CSTRING("sample"),
                                        Telemetry::LABELS_TELEMETRY_TEST_KEYED_CATEGORICAL::CommonLabel);
  // Accumulate another unit into the same categorical histogram
  Telemetry::AccumulateCategoricalKeyed(NS_LITERAL_CSTRING("sample"),
                                        Telemetry::LABELS_TELEMETRY_TEST_KEYED_CATEGORICAL::CommonLabel);
  // Accumulate another unit into a different categorical histogram
  Telemetry::AccumulateCategoricalKeyed(NS_LITERAL_CSTRING("other-sample"),
                                        Telemetry::LABELS_TELEMETRY_TEST_KEYED_CATEGORICAL::CommonLabel);

  // Get a snapshot for all the histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_KEYED_CATEGORICAL", &snapshot, true);
  // Get the histogram from the snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_KEYED_CATEGORICAL", snapshot, &histogram);

  // Check that the sample histogram contains the values we expect
  JS::RootedValue sample(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "sample", histogram,  &sample);
  // Get counts array from the sample. Each entry in the array maps to a label in the histogram.
  JS::RootedValue sampleCounts(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "counts", sample,  &sampleCounts);
  // Get the value for the label we care about
  JS::RootedValue sampleValue(cx.GetJSContext());
  GetElement(cx.GetJSContext(),
             static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_KEYED_CATEGORICAL::CommonLabel),
             sampleCounts, &sampleValue);
  // Check that the value stored in the histogram matches with |kSampleExpectedValue|
  uint32_t uSampleValue = 0;
  JS::ToUint32(cx.GetJSContext(), sampleValue, &uSampleValue);
  ASSERT_EQ(uSampleValue, kSampleExpectedValue) << "The sample histogram is not returning expected value";

  // Check that the other-sample histogram contains the values we expect
  JS::RootedValue otherSample(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "other-sample", histogram,  &otherSample);
  // Get counts array from the other-sample. Each entry in the array maps to a label in the histogram.
  JS::RootedValue otherCounts(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "counts", otherSample,  &otherCounts);
  // Get the value for the label we care about
  JS::RootedValue otherValue(cx.GetJSContext());
  GetElement(cx.GetJSContext(),
             static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_KEYED_CATEGORICAL::CommonLabel),
             otherCounts, &otherValue);
  // Check that the value stored in the histogram matches with |kOtherSampleExpectedValue|
  uint32_t uOtherValue = 0;
  JS::ToUint32(cx.GetJSContext(), otherValue, &uOtherValue);
  ASSERT_EQ(uOtherValue, kOtherSampleExpectedValue) << "The other-sample histogram is not returning expected value";
}

TEST_F(TelemetryTestFixture, AccumulateCountHistogram_MultipleSamples)
{
  nsTArray<uint32_t> samples({4,4,4});
  const uint32_t kExpectedSum = 12;

  AutoJSContextWithGlobal cx(mCleanGlobal);

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry, NS_LITERAL_CSTRING("TELEMETRY_TEST_COUNT"),
                        false);

  // Accumulate in histogram
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_COUNT, samples);

  // Get a snapshot of all the histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_COUNT", &snapshot, false);

  // Get histogram from snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_COUNT", snapshot, &histogram);

  // Get "sum" from histogram
  JS::RootedValue sum(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "sum", histogram, &sum);

  // Check that sum matches with aValue
  uint32_t uSum = 0;
  JS::ToUint32(cx.GetJSContext(), sum, &uSum);
  ASSERT_EQ(uSum, kExpectedSum) << "This histogram is not returning expected value";
}

TEST_F(TelemetryTestFixture, AccumulateLinearHistogram_MultipleSamples)
{
  nsTArray<uint32_t> samples({4,4,4});
  const uint32_t kExpectedCount = 3;

  AutoJSContextWithGlobal cx(mCleanGlobal);

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry, NS_LITERAL_CSTRING("TELEMETRY_TEST_LINEAR"),
                        false);

  // Accumulate in the histogram
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_LINEAR, samples);

  // Get a snapshot of all the histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_LINEAR", &snapshot, false);

  // Get histogram from snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_LINEAR", snapshot, &histogram);

  // Get "counts" array from histogram
  JS::RootedValue counts(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "counts", histogram, &counts);

  // Index 0 is only for values less than 'low'. Values within range start at index 1
  JS::RootedValue count(cx.GetJSContext());
  const uint32_t index = 1;
  GetElement(cx.GetJSContext(), index, counts, &count);

  // Check that this count matches with nSamples
  uint32_t uCount = 0;
  JS::ToUint32(cx.GetJSContext(), count, &uCount);
  ASSERT_EQ(uCount, kExpectedCount) << "The histogram did not accumulate the correct number of values";
}

TEST_F(TelemetryTestFixture, AccumulateLinearHistogram_DifferentSamples)
{
  nsTArray<uint32_t> samples({4, 8, 2147483646});

  AutoJSContextWithGlobal cx(mCleanGlobal);

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry, NS_LITERAL_CSTRING("TELEMETRY_TEST_LINEAR"),
                        false);

  // Accumulate in histogram
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_LINEAR, samples);

  // Get a snapshot of all histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_LINEAR", &snapshot, false);

  // Get histogram from snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_LINEAR", snapshot, &histogram);

  // Get counts array from histogram
  JS::RootedValue counts(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "counts", histogram, &counts);

  // Get counts in first and last buckets
  JS::RootedValue countFirst(cx.GetJSContext());
  JS::RootedValue countLast(cx.GetJSContext());
  const uint32_t firstIndex = 1;
  const uint32_t lastIndex = 9;
  GetElement(cx.GetJSContext(), firstIndex, counts, &countFirst);
  GetElement(cx.GetJSContext(), lastIndex, counts, &countLast);

  // Check that the counts match
  uint32_t uCountFirst = 0;
  uint32_t uCountLast = 0;
  JS::ToUint32(cx.GetJSContext(), countFirst, &uCountFirst);
  JS::ToUint32(cx.GetJSContext(), countLast, &uCountLast);

  const uint32_t kExpectedCountFirst = 2;
  const uint32_t kExpectedCountLast = 1;
  ASSERT_EQ(uCountFirst, kExpectedCountFirst) << "The first bucket did not accumulate the correct number of values";
  ASSERT_EQ(uCountLast, kExpectedCountLast) << "The last bucket did not accumulate the correct number of values";
}

TEST_F(TelemetryTestFixture, AccumulateKeyedCountHistogram_MultipleSamples)
{
  const nsTArray<uint32_t> samples({5, 10, 15});
  const uint32_t kExpectedSum = 5 + 10 + 15;

  AutoJSContextWithGlobal cx(mCleanGlobal);

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry,
                       NS_LITERAL_CSTRING("TELEMETRY_TEST_KEYED_COUNT"), true);

  // Accumulate data in the provided key within the histogram
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_KEYED_COUNT, NS_LITERAL_CSTRING("sample"),
                        samples);

  // Get a snapshot for all the histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_KEYED_COUNT", &snapshot, true);

  // Get the histogram from the snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_KEYED_COUNT", snapshot, &histogram);

  // Get "sample" property from histogram
  JS::RootedValue expectedKeyData(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "sample", histogram,  &expectedKeyData);

  // Get "sum" property from keyed data
  JS::RootedValue sum(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "sum", expectedKeyData,  &sum);

  // Check that the sum stored in the histogram matches with |kExpectedSum|
  uint32_t uSum = 0;
  JS::ToUint32(cx.GetJSContext(), sum, &uSum);
  ASSERT_EQ(uSum, kExpectedSum) << "The histogram is not returning expected sum";
}

TEST_F(TelemetryTestFixture, TestKeyedLinearHistogram_MultipleSamples)
{
  AutoJSContextWithGlobal cx(mCleanGlobal);

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry,
                       NS_LITERAL_CSTRING("TELEMETRY_TEST_KEYED_LINEAR"), true);

  const nsTArray<uint32_t> samples({1,5,250000});
  // Test the accumulation on the key 'testkey', using
  // the API that accepts histogram IDs.
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_KEYED_LINEAR,
                        NS_LITERAL_CSTRING("testkey"), samples);

  // Get a snapshot for all the histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_KEYED_LINEAR", &snapshot, true);

  // Get the histogram from the snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_KEYED_LINEAR", snapshot, &histogram);

  // Get "testkey" property from histogram.
  JS::RootedValue expectedKeyData(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "testkey", histogram,  &expectedKeyData);
  ASSERT_TRUE(!expectedKeyData.isUndefined())
    << "Cannot find the expected key in the histogram data";

  // Get counts array from 'testkey' histogram.
  JS::RootedValue counts(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "counts", expectedKeyData, &counts);

  // Get counts in first and last buckets.
  JS::RootedValue countFirst(cx.GetJSContext());
  JS::RootedValue countLast(cx.GetJSContext());
  const uint32_t firstIndex = 1;
  const uint32_t lastIndex = 9;
  GetElement(cx.GetJSContext(), firstIndex, counts, &countFirst);
  GetElement(cx.GetJSContext(), lastIndex, counts, &countLast);

  // Check that the counts match.
  uint32_t uCountFirst = 0;
  uint32_t uCountLast = 0;
  JS::ToUint32(cx.GetJSContext(), countFirst, &uCountFirst);
  JS::ToUint32(cx.GetJSContext(), countLast, &uCountLast);

  const uint32_t kExpectedCountFirst = 2;
  const uint32_t kExpectedCountLast = 1;
  ASSERT_EQ(uCountFirst, kExpectedCountFirst)
    << "The first bucket did not accumulate the correct number of values for key 'testkey'";
  ASSERT_EQ(uCountLast, kExpectedCountLast)
    << "The last bucket did not accumulate the correct number of values for key 'testkey'";
}

TEST_F(TelemetryTestFixture, TestKeyedKeysHistogram_MultipleSamples)
{
  AutoJSContextWithGlobal cx(mCleanGlobal);
  mTelemetry->ClearScalars();
  const nsTArray<uint32_t> samples({false, false, true, 32, true});

  GetAndClearHistogram(cx.GetJSContext(), mTelemetry,
                       NS_LITERAL_CSTRING("TELEMETRY_TEST_KEYED_KEYS"), true);

  // Test the accumulation on both the allowed and unallowed keys, using
  // the API that accepts histogram IDs.
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_KEYED_KEYS,
                        NS_LITERAL_CSTRING("not-allowed"), samples);
  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_KEYED_KEYS,
                        NS_LITERAL_CSTRING("testkey"), samples);

  // Get a snapshot for all the histograms
  JS::RootedValue snapshot(cx.GetJSContext());
  GetSnapshots(cx.GetJSContext(), mTelemetry, "TELEMETRY_TEST_KEYED_KEYS", &snapshot, true);

  // Get the histogram from the snapshot
  JS::RootedValue histogram(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_KEYED_KEYS", snapshot, &histogram);

  // Get "testkey" property from histogram and check that it stores the correct data.
  JS::RootedValue testKeyData(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "testkey", histogram,  &testKeyData);
  ASSERT_TRUE(!testKeyData.isUndefined())
    << "Cannot find the key 'testkey' in the histogram data";

  JS::RootedValue counts(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "counts", testKeyData,  &counts);

  // Get counts in buckets 0,1,2
  const uint32_t falseIndex = 0;
  const uint32_t trueIndex = 1;
  const uint32_t otherIndex = 2;

  JS::RootedValue countFalse(cx.GetJSContext());
  JS::RootedValue countTrue(cx.GetJSContext());
  JS::RootedValue countOther(cx.GetJSContext());

  GetElement(cx.GetJSContext(), falseIndex, counts, &countFalse);
  GetElement(cx.GetJSContext(), trueIndex, counts, &countTrue);
  GetElement(cx.GetJSContext(), otherIndex, counts, &countOther);

  uint32_t uCountFalse = 0;
  uint32_t uCountTrue = 0;
  uint32_t uCountOther = 0;
  JS::ToUint32(cx.GetJSContext(), countFalse, &uCountFalse);
  JS::ToUint32(cx.GetJSContext(), countTrue, &uCountTrue);
  JS::ToUint32(cx.GetJSContext(), countOther, &uCountOther);

  const uint32_t kExpectedCountFalse = 2;
  const uint32_t kExpectedCountTrue = 3;
  const uint32_t kExpectedCountOther = 0;

  ASSERT_EQ(uCountFalse, kExpectedCountFalse)
    << "The histogram did not accumulate the correct number of 'false' booleans for key 'testkey'";
  ASSERT_EQ(uCountTrue, kExpectedCountTrue)
    << "The histogram did not accumulate the correct number of 'true' booleans for key 'testkey'";
  ASSERT_EQ(uCountOther, kExpectedCountOther)
    << "The histogram did not accumulate the correct number of undefined values for key 'testkey'";

  // Here we check that we are not accumulating to a different (but still 'allowed') key.
  // Get "CommonKey" property from histogram and check that it has no data.
  // Since we accumulated no data to it, commonKeyData should be undefined.
  JS::RootedValue commonKeyData(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "CommonKey", histogram,  &commonKeyData);
  ASSERT_TRUE(commonKeyData.isUndefined())
    << "Found data in key 'CommonKey' even though we accumulated no data to it";

  // Here we check that our function does not allow accumulation into unallowed keys.
  // Get 'not-allowed' property from histogram and check that this also has no data.
  // This should contain no data because this key is not allowed.
  JS::RootedValue notAllowedKeyData(cx.GetJSContext());
  GetProperty(cx.GetJSContext(), "not-allowed", histogram, &notAllowedKeyData);
  ASSERT_TRUE(notAllowedKeyData.isUndefined())
    << "Found data in key 'not-allowed' even though accumuling data to it is not allowed";

  // The 'not-allowed' key accumulation for 'TELEMETRY_TESTED_KEYED_KEYS' was
  // attemtped once, so we expect the count of
  // 'telemetry.accumulate_unknown_histogram_keys' to be 1
  const uint32_t expectedAccumulateUnknownCount = 1;
  JS::RootedValue scalarsSnapshot(cx.GetJSContext());
  GetScalarsSnapshot(true, cx.GetJSContext(),&scalarsSnapshot);
  CheckKeyedUintScalar("telemetry.accumulate_unknown_histogram_keys",
                       "TELEMETRY_TEST_KEYED_KEYS", cx.GetJSContext(),
                       scalarsSnapshot, expectedAccumulateUnknownCount);
}