[MNG-7511] Ensure the degreeOfConcurrency is a positive number in MavenExecutionRequest

[kwart]

JIRA: https://issues.apache.org/jira/browse/MNG-7511

This PR ensures the degreeOfConcurrency is always a positive number (defaulting to 1). It resolves issues when the computed value is < 1.

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[michael-o]

I am not convinced by this. It should throw an IAE here. I would expect to fix the source.

[kwart]

I am not convinced by this. It should throw an IAE here. I would expect to fix the source.

To me, it seems like the safest approach.

Another place to put the fix would be the MavenCli.calculateDegreeOfConcurrencyWithCoreMultiplier(...) method, but I like the protection in the config object more as it handles more cases without doing harm.

Still, if you request the change, I can move the fix to the calculateDegreeOfConcurrencyWithCoreMultiplier(...) method.

[michael-o]

I think I have a better idea for this. First of all the arg need to checked whether it is a really an int or float. The C must be at the end. It must be larger than 0. The IAE still stands. When doing with float we could either use ceiling or floor. And then here set to one when smaller than 1.

[kwart]

The C allowed only at the end would break the backward compatibility, see the MavenCliTest.

So I've added a new commit with additional checks in the MavenCli.calculateDegreeOfConcurrencyWithCoreMultiplier(String) method.

To be honest, the change from the NumberFormatException to IllegalArgumentException is also not backward compatible, but it's not a change on the sunshine call path.

[michael-o]

Picking this up...A breaking change in Maven 4 is fully acceptable.

[michael-o]

@kwart Added a commit on top:

• Using C not at the end was never documented, so it is undefined behavior. Thus, don't rely on
• Change of exception: Well, it is CLI, not for embedding into an IDE or so. For the user on the CLI it does not matter.

I am not 100% happy because there are no methods to verify a true mathematical integer (whole number) and a real (fraction number). But is is likely good enough for now.

WDYT?

[kwart]

👍 LGTM
Thanks for jumping on it.

[michael-o]

@kwart If you want this in Maven 3.9 please provide a followup PR.

[kwart]

@michael-o Thanks for merging.

WRT 3.9 backport: Should I care about the exception type and the -TC<float> format, or should it be rather the 1:1 backport?

[michael-o]

@michael-o Thanks for merging.

WRT 3.9 backport: Should I care about the exception type and the -TC<float> format, or should it be rather the 1:1 backport?

Back port 1:1 because:

• -TC<float> was never documented
• This is a class with a main() not really intended for code use, but both exceptions are still IAE.