nagi1 / hill-chart

import {

  hillFn,

  hillFnInverse,

  textOutRange,

  calculateTextPositionForX,

} from '../src/helpers';

describe('hill chart function', () => {

  it('computes correct values', () => {

    expect.hasAssertions();

    expect(hillFn(0)).toEqual(0);

    expect(hillFn(25)).toEqual(50.000000000000014);

    expect(hillFn(50)).toEqual(100);

    expect(hillFn(100)).toEqual(0);

  });

});

describe('hill chart inverse function', () => {

  it('computes correct values', () => {

    expect.hasAssertions();

    expect(hillFnInverse(0)).toEqual(0);

    expect(hillFnInverse(25)).toEqual(16.666666666666664);

    expect(hillFnInverse(50)).toEqual(25);

    expect(hillFnInverse(100)).toEqual(50);

  });

});

describe('out of range function', () => {

  it('returns true when passed value between 80 and 100', () => {

    expect.hasAssertions();

    expect(textOutRange(20)).toBe(false);

    expect(textOutRange(80)).toBe(true);

    expect(textOutRange(100)).toBe(true);

  });

});

describe('calculate text position on x axis', () => {

  it('returns positive value if text isnt out of range and negative it is. based on the point size and x axis position', () => {

    expect.hasAssertions();

    let pointSize = 10;

    let x = 50;

    expect(calculateTextPositionForX(pointSize, x)).toEqual(15);

    pointSize = 15;

    x = 80;

    expect(calculateTextPositionForX(pointSize, x)).toBe(-20);

  });

});