Improve SafeMath test coverage. (#1611)

* Improve SafeMath test coverage.

* Fix linter error.

* Split testCommutative into something more sane.
This commit is contained in:
Nicolás Venturo
2019-01-21 17:51:35 -03:00
committed by GitHub
parent 07603d5875
commit f80c65ff67
2 changed files with 51 additions and 34 deletions

View File

@ -8,34 +8,43 @@ contract('SignedSafeMath', function () {
this.safeMath = await SignedSafeMathMock.new(); this.safeMath = await SignedSafeMathMock.new();
}); });
async function testCommutative (fn, lhs, rhs, expected) {
(await fn(lhs, rhs)).should.be.bignumber.equal(expected);
(await fn(rhs, lhs)).should.be.bignumber.equal(expected);
}
async function testFailsCommutative (fn, lhs, rhs) {
await shouldFail.reverting(fn(lhs, rhs));
await shouldFail.reverting(fn(rhs, lhs));
}
describe('add', function () { describe('add', function () {
it('adds correctly if it does not overflow and the result is positve', async function () { it('adds correctly if it does not overflow and the result is positve', async function () {
const a = new BN('1234'); const a = new BN('1234');
const b = new BN('5678'); const b = new BN('5678');
(await this.safeMath.add(a, b)).should.be.bignumber.equal(a.add(b)); await testCommutative(this.safeMath.add, a, b, a.add(b));
}); });
it('adds correctly if it does not overflow and the result is negative', async function () { it('adds correctly if it does not overflow and the result is negative', async function () {
const a = MAX_INT256; const a = MAX_INT256;
const b = MIN_INT256; const b = MIN_INT256;
const result = await this.safeMath.add(a, b); await testCommutative(this.safeMath.add, a, b, a.add(b));
result.should.be.bignumber.equal(a.add(b));
}); });
it('reverts on positive addition overflow', async function () { it('reverts on positive addition overflow', async function () {
const a = MAX_INT256; const a = MAX_INT256;
const b = new BN('1'); const b = new BN('1');
await shouldFail.reverting(this.safeMath.add(a, b)); await testFailsCommutative(this.safeMath.add, a, b);
}); });
it('reverts on negative addition overflow', async function () { it('reverts on negative addition overflow', async function () {
const a = MIN_INT256; const a = MIN_INT256;
const b = new BN('-1'); const b = new BN('-1');
await shouldFail.reverting(this.safeMath.add(a, b)); await testFailsCommutative(this.safeMath.add, a, b);
}); });
}); });
@ -76,37 +85,28 @@ contract('SignedSafeMath', function () {
const a = new BN('5678'); const a = new BN('5678');
const b = new BN('-1234'); const b = new BN('-1234');
const result = await this.safeMath.mul(a, b); await testCommutative(this.safeMath.mul, a, b, a.mul(b));
result.should.be.bignumber.equal(a.mul(b));
}); });
it('handles a zero product correctly', async function () { it('multiplies by zero correctly', async function () {
const a = new BN('0'); const a = new BN('0');
const b = new BN('5678'); const b = new BN('5678');
const result = await this.safeMath.mul(a, b); await testCommutative(this.safeMath.mul, a, b, '0');
result.should.be.bignumber.equal(a.mul(b));
}); });
it('reverts on multiplication overflow, positive operands', async function () { it('reverts on multiplication overflow, positive operands', async function () {
const a = MAX_INT256; const a = MAX_INT256;
const b = new BN('2'); const b = new BN('2');
await shouldFail.reverting(this.safeMath.mul(a, b)); await testFailsCommutative(this.safeMath.mul, a, b);
}); });
it('reverts when minimum integer is multiplied by -1', async function () { it('reverts when minimum integer is multiplied by -1', async function () {
const a = MIN_INT256; const a = MIN_INT256;
const b = new BN('-1'); const b = new BN('-1');
await shouldFail.reverting(this.safeMath.mul(a, b)); await testFailsCommutative(this.safeMath.mul, a, b);
});
it('reverts when -1 is multiplied by minimum integer', async function () {
const a = new BN('-1');
const b = MIN_INT256;
await shouldFail.reverting(this.safeMath.mul(a, b));
}); });
}); });
@ -119,7 +119,21 @@ contract('SignedSafeMath', function () {
result.should.be.bignumber.equal(a.div(b)); result.should.be.bignumber.equal(a.div(b));
}); });
it('reverts on zero division', async function () { it('divides zero correctly', async function () {
const a = new BN('0');
const b = new BN('5678');
(await this.safeMath.div(a, b)).should.be.bignumber.equal('0');
});
it('returns complete number result on non-even division', async function () {
const a = new BN('7000');
const b = new BN('5678');
(await this.safeMath.div(a, b)).should.be.bignumber.equal('1');
});
it('reverts on division by zero', async function () {
const a = new BN('-5678'); const a = new BN('-5678');
const b = new BN('0'); const b = new BN('0');

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@ -8,19 +8,29 @@ contract('SafeMath', function () {
this.safeMath = await SafeMathMock.new(); this.safeMath = await SafeMathMock.new();
}); });
async function testCommutative (fn, lhs, rhs, expected) {
(await fn(lhs, rhs)).should.be.bignumber.equal(expected);
(await fn(rhs, lhs)).should.be.bignumber.equal(expected);
}
async function testFailsCommutative (fn, lhs, rhs) {
await shouldFail.reverting(fn(lhs, rhs));
await shouldFail.reverting(fn(rhs, lhs));
}
describe('add', function () { describe('add', function () {
it('adds correctly', async function () { it('adds correctly', async function () {
const a = new BN('5678'); const a = new BN('5678');
const b = new BN('1234'); const b = new BN('1234');
(await this.safeMath.add(a, b)).should.be.bignumber.equal(a.add(b)); await testCommutative(this.safeMath.add, a, b, a.add(b));
}); });
it('reverts on addition overflow', async function () { it('reverts on addition overflow', async function () {
const a = MAX_UINT256; const a = MAX_UINT256;
const b = new BN('1'); const b = new BN('1');
await shouldFail.reverting(this.safeMath.add(a, b)); await testFailsCommutative(this.safeMath.add, a, b);
}); });
}); });
@ -45,28 +55,21 @@ contract('SafeMath', function () {
const a = new BN('1234'); const a = new BN('1234');
const b = new BN('5678'); const b = new BN('5678');
(await this.safeMath.mul(a, b)).should.be.bignumber.equal(a.mul(b)); await testCommutative(this.safeMath.mul, a, b, a.mul(b));
}); });
it('handles a zero product correctly (first number as zero)', async function () { it('multiplies by zero correctly', async function () {
const a = new BN('0'); const a = new BN('0');
const b = new BN('5678'); const b = new BN('5678');
(await this.safeMath.mul(a, b)).should.be.bignumber.equal(a.mul(b)); await testCommutative(this.safeMath.mul, a, b, '0');
});
it('handles a zero product correctly (second number as zero)', async function () {
const a = new BN('5678');
const b = new BN('0');
(await this.safeMath.mul(a, b)).should.be.bignumber.equal(a.mul(b));
}); });
it('reverts on multiplication overflow', async function () { it('reverts on multiplication overflow', async function () {
const a = MAX_UINT256; const a = MAX_UINT256;
const b = new BN('2'); const b = new BN('2');
await shouldFail.reverting(this.safeMath.mul(a, b)); await testFailsCommutative(this.safeMath.mul, a, b);
}); });
}); });
@ -92,7 +95,7 @@ contract('SafeMath', function () {
(await this.safeMath.div(a, b)).should.be.bignumber.equal('1'); (await this.safeMath.div(a, b)).should.be.bignumber.equal('1');
}); });
it('reverts on zero division', async function () { it('reverts on divison by zero', async function () {
const a = new BN('5678'); const a = new BN('5678');
const b = new BN('0'); const b = new BN('0');