How to use local project files in build.rs script?

Question

How do I use local files without including their absolute paths in build.rs? I have, for example let proto_file_glob_paths: Paths = glob("../proto/**/*.proto").unwrap();.

I am using relative paths in my build.rs, because I don't want to hardcode the absolute path of files, so that it works on other developer machines. The build works fine with cargo build and cargo run, but not cargo publish. This is because the working directory/path is different when cargo publish is run.

In cargo build, the env::current_dir() is:

project_name/target/debug/build/project_name-70e21ac88134b5a1/build-script-build

In cargo publish, the env::current_dir() is:

project_name/target/package/project_name-x.y.z/target/debug/build/project_name-xxxxxxx/build-script-build

I don't know of any environment variables I can use to access the directory of build.rs, or src/, so that I can create a relative/absolute path dynamically. Even CARGO_MANIFEST_DIR is different for build and publish.

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Project specifics: I've got other lines of code to generate the rust code using other packages, and this works fine in cargo build and cargo run.

Answer 1

After some very helpful prompting from @Cerberus and then from @ColonelThirtyTwo, I just:

• copied the local files into the crate root. I wrote a script to do this before running cargo build. Of course, I needed to update the relative path to use proto/ instead of ../proto/.
• added the proto directory to the gitignore file
• and added the proto directory to package.include in Cargo.toml because it would not be included as it is gitignored:

[package]
...
include = ["**/*.rs", "Cargo.toml", "Cargo.lock", "config.json", "proto"]

My mistakes were that:

• I assumed ../proto should work, but as Cerberus explained, it won't. Since the files would be missing for the users of the crate.
• I didn't add the proto file to include in Cargo.toml