faker.helpers.maybe doesn't always invoke callback with { probability: 1 }

[NvGary]

Pre-Checks

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• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
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• The provided reproduction is a minimal reproducible example of the bug.
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Describe the bug

If you execute this block enough times you will experience an intermittent failure.

describe('maybe', () => {
    it('should always return the callback result when probability is 1', () => {
        const actual = faker.helpers.maybe(() => 'foo', { probability: 1 });

        expect(actual).toBe('foo');
    });
});

On dry reading the code this can happen when faker.datatype.float({ min: 0, max: 1}) returns 1. The subsequent 1 < 1 check fails and the callback is never executed.

Minimal reproduction code

describe('maybe', () => {
    it('should always return the callback result when probability is 1', () => {
        jest.spyOn(faker.datatype, 'float').mockReturnValueOnce(1);
        const actual = faker.helpers.maybe(() => 'foo', { probability: 1 });

        expect(actual).toBe('foo');
    });
});

Additional Context

A quick 1 <= 1 fix won't work as maybe should fail { probability: 0 } and faker.datatype.float returning 0.

Environment Info

System:
    OS: macOS 12.6.1
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
    Memory: 772.65 MB / 16.00 GB
    Shell: 5.8.1 - /bin/zsh
  Binaries:
    Node: 16.15.0 - ~/.nvm/versions/node/v16.15.0/bin/node
    npm: 8.5.5 - ~/.nvm/versions/node/v16.15.0/bin/npm
  Browsers:
    Chrome: 108.0.5359.124
    Safari: 16.1

Which module system do you use?

• CJS
• ESM

Used Package Manager

npm

[ST-DDT]

Which version are you testing on?

faker/src/modules/helpers/index.ts

Lines 401 to 406 in 2a06b6a

	if (this.faker.datatype.boolean(options)) {
	return callback();
	}
	return undefined;
	}

faker/src/modules/datatype/index.ts

Lines 221 to 224 in 2a06b6a

	if (probability >= 1) {
	// This check is required to avoid returning false when float() returns 1
	return true;
	}

Should catch probability == 1 and return true.

[ST-DDT]

Yes in v7.6.0 that is a bug, but we fixed it since.

Fixed in #1476

Thanks for bringing this to our attention anyway.

[NvGary]

Schoolboy error. Was working on 7.6.0. Should have checked the latest version 🤦