squiggle/packages/squiggle-lang/__tests__/TS/JS_test.ts

import {
  run,
  Distribution,
  resultMap,
  squiggleExpression,
  errorValueToString,
} from "../../src/js/index";

let testRun = (x: string): squiggleExpression => {
  let result = run(x, { sampleCount: 100, xyPointLength: 100 });
  expect(result.tag).toEqual("Ok");
  if (result.tag === "Ok") {
    return result.value;
  } else {
    throw Error(
      "Expected squiggle expression to evaluate but got error: " +
        errorValueToString(result.value)
    );
  }
};

function Ok<b>(x: b) {
  return { tag: "Ok", value: x };
}

describe("Simple calculations and results", () => {
  test("mean(normal(5,2))", () => {
    expect(testRun("mean(normal(5,2))")).toEqual({
      tag: "number",
      value: 5,
    });
  });
  test("10+10", () => {
    let foo = testRun("10 + 10");
    expect(foo).toEqual({ tag: "number", value: 20 });
  });
});
describe("Log function", () => {
  test("log(1) = 0", () => {
    let foo = testRun("log(1)");
    expect(foo).toEqual({ tag: "number", value: 0 });
  });
});

describe("Distribution", () => {
  //It's important that sampleCount is less than 9. If it's more, than that will create randomness
  //Also, note, the value should be created using makeSampleSetDist() later on.
  let env = { sampleCount: 8, xyPointLength: 100 };
  let dist1Samples = [3, 4, 5, 6, 6, 7, 10, 15, 30];
  let dist1SampleCount = dist1Samples.length;
  let dist = new Distribution(
    { tag: "SampleSet", value: [3, 4, 5, 6, 6, 7, 10, 15, 30] },
    env
  );
  let dist2 = new Distribution(
    { tag: "SampleSet", value: [20, 22, 24, 29, 30, 35, 38, 44, 52] },
    env
  );

  test("mean", () => {
    expect(dist.mean().value).toBeCloseTo(8.704375514292865);
  });
  test("pdf", () => {
    expect(dist.pdf(5.0).value).toBeCloseTo(0.052007455285386944, 1);
  });
  test("cdf", () => {
    expect(dist.cdf(5.0).value).toBeCloseTo(
      dist1Samples.filter((x) => x <= 5).length / dist1SampleCount
    );
  });
  test("inv", () => {
    expect(dist.inv(0.5).value).toBeCloseTo(6);
  });
  test("toPointSet", () => {
    expect(
      resultMap(dist.toPointSet(), (r: Distribution) => r.toString())
    ).toEqual(Ok("Point Set Distribution"));
  });
  test("toSparkline", () => {
    expect(dist.toSparkline(20).value).toEqual("▁▁▃▅███▆▄▃▂▁▁▂▂▃▂▁▁▁");
  });
  test("algebraicAdd", () => {
    expect(
      resultMap(dist.algebraicAdd(dist2), (r: Distribution) =>
        r.toSparkline(20)
      ).value
    ).toEqual(Ok("▁▁▂▄▆████▇▆▄▄▃▃▃▂▁▁▁"));
  });
  test("pointwiseAdd", () => {
    expect(
      resultMap(dist.pointwiseAdd(dist2), (r: Distribution) =>
        r.toSparkline(20)
      ).value
    ).toEqual(Ok("▁▂▅██▅▅▅▆▆▇▅▄▃▃▂▂▁▁▁"));
  });
});