Transpile 7bce2b72

test/utils/math/Math.test.js

@@ -0,0 +1,104 @@
+const { BN, constants } = require('@openzeppelin/test-helpers');
+const { expect } = require('chai');
+const { MAX_UINT256, MAX_INT256, MIN_INT256 } = constants;
+
+const MathMock = artifacts.require('MathMock');
+
+contract('Math', function (accounts) {
+  const min = new BN('1234');
+  const max = new BN('5678');
+
+  beforeEach(async function () {
+    this.math = await MathMock.new();
+  });
+
+  describe('max', function () {
+    it('is correctly detected in first argument position', async function () {
+      expect(await this.math.max(max, min)).to.be.bignumber.equal(max);
+    });
+
+    it('is correctly detected in second argument position', async function () {
+      expect(await this.math.max(min, max)).to.be.bignumber.equal(max);
+    });
+  });
+
+  describe('min', function () {
+    it('is correctly detected in first argument position', async function () {
+      expect(await this.math.min(min, max)).to.be.bignumber.equal(min);
+    });
+
+    it('is correctly detected in second argument position', async function () {
+      expect(await this.math.min(max, min)).to.be.bignumber.equal(min);
+    });
+  });
+
+  describe('average', function () {
+    function bnAverage (a, b) {
+      return a.add(b).divn(2);
+    }
+
+    it('is correctly calculated with two odd numbers', async function () {
+      const a = new BN('57417');
+      const b = new BN('95431');
+      expect(await this.math.average(a, b)).to.be.bignumber.equal(bnAverage(a, b));
+    });
+
+    it('is correctly calculated with two even numbers', async function () {
+      const a = new BN('42304');
+      const b = new BN('84346');
+      expect(await this.math.average(a, b)).to.be.bignumber.equal(bnAverage(a, b));
+    });
+
+    it('is correctly calculated with one even and one odd number', async function () {
+      const a = new BN('57417');
+      const b = new BN('84346');
+      expect(await this.math.average(a, b)).to.be.bignumber.equal(bnAverage(a, b));
+    });
+
+    it('is correctly calculated with two max uint256 numbers', async function () {
+      const a = MAX_UINT256;
+      expect(await this.math.average(a, a)).to.be.bignumber.equal(bnAverage(a, a));
+    });
+  });
+
+  describe('ceilDiv', function () {
+    it('does not round up on exact division', async function () {
+      const a = new BN('10');
+      const b = new BN('5');
+      expect(await this.math.ceilDiv(a, b)).to.be.bignumber.equal('2');
+    });
+
+    it('rounds up on division with remainders', async function () {
+      const a = new BN('42');
+      const b = new BN('13');
+      expect(await this.math.ceilDiv(a, b)).to.be.bignumber.equal('4');
+    });
+
+    it('does not overflow', async function () {
+      const b = new BN('2');
+      const result = new BN('1').shln(255);
+      expect(await this.math.ceilDiv(MAX_UINT256, b)).to.be.bignumber.equal(result);
+    });
+
+    it('correctly computes max uint256 divided by 1', async function () {
+      const b = new BN('1');
+      expect(await this.math.ceilDiv(MAX_UINT256, b)).to.be.bignumber.equal(MAX_UINT256);
+    });
+  });
+
+  describe('abs', function () {
+    for (const n of [
+      MIN_INT256,
+      MIN_INT256.addn(1),
+      new BN('-1'),
+      new BN('0'),
+      new BN('1'),
+      MAX_INT256.subn(1),
+      MAX_INT256,
+    ]) {
+      it(`correctly computes the absolute value of ${n}`, async function () {
+        expect(await this.math.abs(n)).to.be.bignumber.equal(n.abs());
+      });
+    }
+  });
+});