Replaced version (unittest) with version (StdUnittest) to avoid unnecessary overhead when compiling with -unittest

[alexandrumc]

Related to dlang/druntime#2888

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[CyberShadow]

Won't this break compiling user programs with -unittest? Meaning, due to -unittest, DMD will try to parse Phobos unittests too, which will now fail due to required definitions being versioned out?

[alexandrumc]

Won't this break compiling user programs with -unittest? Meaning, due to -unittest, DMD will try to parse Phobos unittests too, which will now fail due to required definitions being versioned out?

No, because parsing doesn't have anything to do with valid definitions. Semantic analysis checks if the referred symbols are defined or not, but it is not done on the unittest {} blocks that are located in libraries.

[CyberShadow]

No, because parsing doesn't have anything to do with valid definitions.

Sorry for using the wrong term :)

Semantic analysis checks if the referred symbols are defined or not, but it is not done on the unittest {} blocks placed in libraries.

Meaning, DMD will not look inside unittest blocks for files that are not on its command line, even with -unittest. I see.

Then, the question is, why not make version(unittest) behave the same way as unittest blocks? I.e. make the compiler ignore them if the file is not on its command line.

[alexandrumc]

Then, the question is, why not make version(unittest) behave the same way as unittest blocks? I.e. make the compiler ignore them if the file is not on its command line.

Sure, a design decision must be made. However, we have to take into account the fact that version {} and unittest {} are different mechanisms, and ignoring version (unittest) might be only an unwanted particular case.

[alexandrumc]

@atilaneves

[MoonlightSentinel]

Why include druntime's unittests with CoreUnittest?

[alexandrumc]

Phobos uses https://github.com/dlang/druntime/blob/9baf9735c923a9bbb72b8e4ee05f513ea0499bbc/src/core/time.d#L120-L123 to run its unittests. But that version (unittest) will change into version (CoreUnittest) (dlang/druntime#2902), so the flag has to be there.

[MoonlightSentinel]

Right, -unittest cascades into druntime. Thanks for the explaination.

[PetarKirov]

Should now be not necessary with my changes to dlang/druntime#2902.

[PetarKirov]

Addressed in #7356.