DUB_PACKAGE/DUB_PACKAGE_DIR is wrong for (pre|post)BuildCommands

[Abscissa]

Within (pre|post)BuildCommands, the DUB_PACKAGE/DUB_PACKAGE_DIR envvars are set to the root package instead of the current package. But they do work correctly within (pre|post)GenerateCommands.

The cause appears to be BuildGenerator.buildTarget(), BuildGenerator.performCachedBuild() and BuildGenerator.performDirectBuild() passing the wrong Package into runBuildCommands(). Still looking into this further.

[Abscissa]

Oh, I see what's going on. DUB combines all (pre|post)BuildCommands into one big (pre|post)BuildCommands list (well, one "pre" and one "post") as part of the BuildSettings for the root package. Then it makes one call to runBuildCommands(), just for the root package, passing all the build commands for all dependencies at once.

I'm not sure what to do about that.

[MartinNowak]

This makes sense b/c building many small libraries is just one strategy, another one would be to build everything at once.

[Abscissa]

Regardless of why BuildCommands should or shouldn't be batched together, DUB_PACKAGE/DUB_PACKAGE_DIR still need to be correct. Currently, they are often incorrect.

[nicolasjinchereau]

I'm trying to use $DUB_PACKAGE in both preGenerateCommands and preBuildCommands, but in both places, I get this error:

Invalid variable: DUB_PACKAGE

I have this in a library project:

"preBuildCommands":` [ "(cd src/cpp && make -f build.mk)" ],

When I build this library directly, the above command runs fine. If I use the same project as a dependency, get an error because dub tries to run that command in the directory of the dependant project.

Running (cd src/cpp && make -f build.mk)
/bin/sh: line 0: cd: src/cpp: No such file or directory

Paths in dub.json should not change meaning depending on whether the project is compiled directly or as a dependency.