fast-check examples

fast-check.example.js

describe("fast-check test", () => {
  before(async () => {
      // generate 10 random records
  });
    
  it("#1", async () => {
    const result = await getMoney(100);
    expect(result.length).to.be.equal(10);
  });

  it("#2", async () => {
    await fc.assert(
      fc.asyncProperty(fc.integer(), async (i) => {
        const result = await getMoney(i);
        return result.length <= 10 && result.length >= 0;
      })
    );
  });

  it("#3", async () => {
    await fc.assert(
      fc.asyncProperty(fc.integer({ min: 0, max: 10 }), async (i) => {
        const result = await getMoney(i);
        return result.length === i;
      })
    );
  });

  it("#4", async () => {
    await fc.assert(
      fc.asyncProperty(fc.integer(), async (i) => {
        const result = await getMoney(i);
        if (result.length > 1) {
          let prev = parseFloat(result[0]);
          for (let i = 1; i < result.length; i++) {
            const curr = parseFloat(result[i]);
            if (curr < prev) {
              return false;
            }
            prev = curr;
          }
        }
        return true;
      })
    );
  });
});