Improve JUnit Vintage docs about parallel execution

[etrandafir93]

Issue: #4321

Overview

Improving user guide section about parallel test execution at class/methods level with JUnit Vintage.

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Definition of Done

• (n/a) There are no TODOs left in the code
• (n/a) Method preconditions are checked and documented in the method's Javadoc
• (n/a) Coding conventions (e.g. for logging) have been followed
• (n/a) Change is covered by automated tests including corner cases, errors, and exception handling
• (n/a) Public API has Javadoc and @API annotations
• (n/a) Change is documented in the User Guide and Release Notes

[YongGoose]

It would be great to add documentation for the following cases as well.

The document looks much better now.
Thank you! 🙂

junit.vintage.execution.parallel.enabled=false
junit.vintage.execution.parallel.classes=true
junit.vintage.execution.parallel.methods=true

[etrandafir93]

junit.vintage.execution.parallel.enabled=false
junit.vintage.execution.parallel.classes=true
junit.vintage.execution.parallel.methods=true

@YongGoose - thanks for the feedback. I have updated the PR now addressing the comments.
I have broken down the content into 4 short subsections, as the main section grew.

I have added the example above as well as the case where parallel execution is enabled but no parallel execution level is defined - to highlight this misconfiguration as well.

Let me know what you think:)

[YongGoose]

@YongGoose - thanks for the feedback. I have updated the PR now addressing the comments.
I have broken down the content into 4 short subsections, as the main section grew.

I have added the example above as well as the case where parallel execution is enabled but no parallel execution level is defined - to highlight this misconfiguration as well.

Let me know what you think:)

LGTM 👍

[YongGoose]

I think explaining one concept at a time (classes, methods, both, pool size, and then sequential execution) would be easier to follow. Therefore, I'd omit it here and introduce a new "Configuring the Pool Size" subsection before the "Sequential Execution" one.

Actually, explaining the pool size together was my own idea, as mentioned in the comment below. 😅

• Improve JUnit Vintage docs about parallel execution #4336 (comment)

@etrandafir93 I apologize for any confusion it may have caused.
It seems better to explain it in a separate section, following Marc’s suggestion.

[etrandafir93]

I think explaining one concept at a time (classes, methods, both, pool size, and then sequential execution) would be easier to follow. Therefore, I'd omit it here and introduce a new "Configuring the Pool Size" subsection before the "Sequential Execution" one.

Actually, explaining the pool size together was my own idea, as mentioned in the comment below. 😅

• Improve JUnit Vintage docs about parallel execution #4336 (comment)

@etrandafir93 I apologize for any confusion it may have caused. It seems better to explain it in a separate section, following Marc’s suggestion.

@YongGoose No worries, it was a good discussion 👍 Also, I've noticed that the pool-size parameter is used internally to define the executor's parallelism level, which is slightly different. I've added a short sentence about this.

@marcphilipp thanks for the feedback, I have applied your suggestions now, let me know what you think.

[marcphilipp]

@etrandafir93 Thank you! 👍