"mocking" tools/dependencies in meson setup?

[jjmaestro]

I'd like to gather information about a repo without having to fully build it.

I found the meson-info/*.json files (and meson introspect) quite useful, it's almost everything I need.

My problem is that the meson-info / introspection provides information about a configured build and I would like to have info about "all of the potential builds". That is, I'd like to be able to get the introspection info "forcing" certain build options and/or dependencies.

For example, say I have a main meson.build at the root of the project with:

(...)
ssl = dependency('openssl', required: false)
(...)

and a subdir with a meson.build that starts with

if not ssl.found()
  subdir_done()
endif
(...)

If I don't have openssl installed, then I won't be able to e.g. get any info for that subdir in the intro-install_plan.json or in meson introspect.

Thus, my question:

Is there a way to parse / evaluate the meson.build files directly? And/or run meson setup "mocking" some of the dependencies so that I could get all the info I need in meson-info / meson introspect?

By mocking I mean making Meson assume a certain tool in a certain path exists so that <DEP>.found() will return True. Then, I'd have to build some script that turns whatever options / dependencies on-and-off.

I assume that this would work because meson setup won't be running anything / any tool except meson itself. Or am I wrong and meson setup can run whatever it wants?

Thanks!

[dcbaker]

At the very least Meson going to run any compilers you need and pkg-config.

The easiest way to for Meson to find dependencies is probably to replace pkg-config with something that will return found for the dependencies you want, and not found otherwise. Meson's interpreter works node by node, so Meson will never seen branches it doesn't go down at all, which makes what you want to do somewhat difficult to achieve, but probably with a some clever replacement of pkg-config and your compilers you could do it for most projects.

[jjmaestro]

Cool, thanks! I was checking Dependency detection method in the docs and there's more than one way although it definitely looks like pkg-config might cover most of the cases.

I'll see if I can come up with a replacement of sorts, thanks for the idea!