Propagate cargo_build_script.data to Rustc compile actions

[UebelAndre]

This way any outputs that the build script may refer to in flags it emits can be referenced without needing to also explicitly pass the data target to the compile_data attribute of it's consumer.

[goffrie]

Is there any way to opt out of this? We have some rules where we want data to only be provided to the build script (admittedly the situation is a pile of hacks, and this is just what broke the camel's back).

[UebelAndre]

Is there any way to opt out of this? We have some rules where we want data to only be provided to the build script (admittedly the situation is a pile of hacks, and this is just what broke the camel's back).

If the data is only for the build script would assigning it to tools do the trick for you? That shouldn't be propagated beyond the build script

rules_rust/cargo/private/cargo_build_script_wrapper.bzl

Line 112 in 0f0b354

tools (list, optional): Tools (executables) needed by the build script.

I'm otherwise not opposed to an incompatibility flag, but when making this change I thought that would cover such a use case.

[illicitonion]

I'm not sure an incompatibility flag would make sense for this one long-term, but an extra attr on cargo_build_script for non_propagated_data or something may?

[goffrie]

tools is built for the exec configuration unfortunately, which does matter for my use case. I agree that adding an incompatibility flag doesn't make much sense, but adding yet another attr seems unfortunate too :/