[allure-jest] Test start time is incorrect, which leads to incorrect test duration

[maks-rafalko]

Describe the bug

We are using v2.15.1 and this version incorrectly calculates tests' start time, which leads to incorrectly calculated Duration time on allure report UI.

The instance of AllureTest is created here on Jest's add_test event:

https://github.com/allure-framework/allure-js/blob/d426d79b63386c42c854ede724c36b582e9b3512/packages/allure-jest/src/AllureJest.ts#L95-L98

Then, we set time to test.testResult.start:

https://github.com/allure-framework/allure-js/blob/d426d79b63386c42c854ede724c36b582e9b3512/packages/allure-js-commons/src/current/AllureTest.ts#L21

The root of the bug is that we should save start time on test_start event, not on add_test. Here:

https://github.com/allure-framework/allure-js/blob/d426d79b63386c42c854ede724c36b582e9b3512/packages/allure-jest/src/AllureJest.ts#L101-L103

add_test event occures for all the tests cases of the fille at the same time, so this is simply not a correct event to save start time of the test..

To Reproduce

1. Create a test file with N tests, let's say N=5
2. in each test() case, add for example sleep for 3 seconds
3. Result - duration of the test N1 will be 3 seconds, duration of the test N2 will be 6 seconds, of the test N3 9 seconds and so on

Expected behavior

1. Create a test file with N tests, let's say N=5
2. in each test() case, add for example sleep for 3 seconds
3. Result - duration of the test N1 will be 3 seconds, duration of the test N2 will be 3 seconds, of the test N3 3 seconds and so on

Screenshots

Before:

After adding a fix:

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The fix is pretty simple, we just need to save test.testResult.start time somewere here on test_start event:

https://github.com/allure-framework/allure-js/blob/d426d79b63386c42c854ede724c36b582e9b3512/packages/allure-jest/src/AllureJest.ts#L179

If you agree, I can try to provide a PR.