source: trip-planner-front/node_modules/hdr-histogram-js/src/HistogramLogWriter.spec.ts

import HistogramLogWriter from "./HistogramLogWriter";
import Int32Histogram from "./Int32Histogram";

describe("Histogram Log Writer", () => {
  let buffer: string;
  let writer: HistogramLogWriter;
  let histogram: Int32Histogram;
  beforeEach(() => {
    buffer = "";
    writer = new HistogramLogWriter((content) => {
      buffer += content;
    });
    histogram = new Int32Histogram(1, Number.MAX_SAFE_INTEGER, 3);
  });

  it("should write a line with start time, duration, max value, and a base64 encoded histogram", () => {
    // given
    histogram.recordValue(123000);
    // when
    writer.outputIntervalHistogram(histogram, 1000, 1042);
    // then
    expect(buffer).toMatch(/^1000.000,42.000,123.000,HISTFAA/);
  });

  it("should write start time, duration and  max value using 3 digits", () => {
    // given
    histogram.recordValue(123001);
    // when
    writer.outputIntervalHistogram(histogram, 1000.0120001, 1042.013001);
    // then
    expect(buffer).toMatch(/^1000.012,42.001,123.001,HISTFAA/);
  });

  it("should write a line starting with histogram tag", () => {
    // given
    histogram.tag = "TAG";
    histogram.recordValue(123000);
    // when
    writer.outputIntervalHistogram(histogram, 1000, 1042);
    // then
    expect(buffer).toContain("Tag=TAG,1000.000,42.000,123.000,HISTFAA");
  });

  it("should write a histogram's start time in sec using basetime", () => {
    // given
    histogram.startTimeStampMsec = 1234001;
    histogram.endTimeStampMsec = 1235001;
    writer.baseTime = 1000000;
    histogram.recordValue(1);
    // when
    writer.outputIntervalHistogram(histogram);
    // then
    expect(buffer).toContain("234.001");
  });

  it("should write start time in seconds", () => {
    // given
    // when
    writer.outputStartTime(1234560);
    // then
    expect(buffer).toContain("1234.560");
  });
});