Percentage of tests passed is rounded up

[AbdelHajou]

In the HTML report after running a test suite, the percentage of tests passed is rounded up. This should not be happening, as it could incorrectly indicate that 100% of tests passed even though 1 of the tests failed (the percentage would be 99,6% for example).

I'm using cucumber-java version 7.3.4 and the same version of cucumber-junit

[mpkorstanje]

Happy to take a pull request for this.

If some one wants to take a look, the code that calculates the percentage is here.

react-components/src/components/app/ExecutionSummary.tsx

Lines 48 to 51 in c27b94c

	const percentagePassed: string =
	new Intl.NumberFormat(undefined, {
	style: 'percent',
	}).format(scenarioCountByStatus[TestStepResultStatus.PASSED] / totalScenarioCount) + ' passed'

[mushahidq]

Including maximumSignificantDigits in options for Intl.NumberFormat allows for decimal places.

const number = parseFloat((277/278).toFixed(10));
console.log(number)
// Expected output: 0.9964028777

console.log(new Intl.NumberFormat(undefined, { style: 'percent'}).format(number));
// Expected output: "100%"

console.log(new Intl.NumberFormat(undefined, { style: 'percent', maximumSignificantDigits: 5}).format(number));
// Expected output: "99.6%"

What would be the appropriate value for maximumSignificantDigits to use? I can make a PR with the same

[mpkorstanje]

I don't think that is the right solution. Try with const number = 0.999999999;

[davidjgoss]

We might consider 2 decimal places but always rounding down.

[mushahidq]

@mpkorstanje It rounds up to 100% for const number = 0.999999999;
We. can parse to less decimal places if needed first.

let number = parseFloat((0.999999999).toFixed(10));
console.log(number)
// Expected output: 0.999999999

console.log(new Intl.NumberFormat(undefined, { style: 'percent'}).format(number));
// Expected output: "100%"

console.log(new Intl.NumberFormat(undefined, { style: 'percent', maximumSignificantDigits: 5}).format(number));
// Expected output: "100%"

number = parseFloat((0.9999).toFixed(10));
console.log(number)
// Expected output: 0.9999

console.log(new Intl.NumberFormat(undefined, { style: 'percent'}).format(number));
// Expected output: "100%"

console.log(new Intl.NumberFormat(undefined, { style: 'percent', maximumSignificantDigits: 5}).format(number));
// Expected output: "99.99%"

[mpkorstanje]

@mushahidq the problem that needs to be solved is that if there is 1 out of N failing tests for any positive non-zero value of N, the reported percentage should not be 100%. While you are suggesting the right solution, your example code doesn't accurately reflect that solution because you changed the input value from 0.999999999 to 0.9999 prior to rounding it.

If you do know the right solution, please do feel free to send a pull request. Otherwise you may have to find someone else first to coach you through this.

[mushahidq]

@mpkorstanje I apologise, I was testing using the same code segments for both cases hence the error. Someone had mentioned that rounding down to 2 decimal places might be considered so I was trying to provide an example of that where the number is round down before being passed to the formatter. Like for example using Math.floor(0.9999999999 * 10000) / 10000

[AbdelHajou]

I would suggest to just round down instead of up, to the nearest full number. I’d imagine displaying 99% of tests passed when it’s actually 99,6% wouldn’t matter as much as displaying 100%