[Rust] error: an inner attribute is not permitted in this context - #4968 regression

[rib]

Commit 9fa1d27 re-introduces #![allow(unused_imports, dead_code)] into generated rust code which causes the same error that was once resolved by #4968 and #5013

The same as @csmoe we include generated rust code like:

mod foo {
    include!(concat!(env!("OUT_DIR"), "/protocol_generated.rs"));
}

Considering that our build.rs script generates the code in Cargo's given build directory as opposed to generating and storing our code in the src/ directory.

This is the error I see:

error: an inner attribute is not permitted in this context
 --> /home/rib/src/realfit-rest-apis/target/debug/build/workoutdb-b7c2283dc82717f7/out/flatbuffers/RFWorkouts_generated.rs:4:1
  |
4 | #![allow(unused_imports, dead_code)]
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: inner attributes, like `#![no_std]`, annotate the item enclosing them, and are usually found at the beginning of source files. Outer attributes, like `#[test]`, annotate the item following them.

We can't follow the approach used by the tutorials of doing:

#[allow(dead_code, unused_imports)]
#[path = "./monster_generated.rs"]
mod monster_generated;

since it's not possible to concatenate the path to OUT_DIR within #[path = ]

[CasperN]

This just entails removing the allow clause at the root of the file right? This means schema-writers who don't use namespaces have to write their own allows, which isn't too bad.

You might want to comment on: #5589 (comment)

• I'm trying to figure out how to better manage C-style namespaces in Rust.

[rib]

Right, I think it's just a question of removing any #![] directives from the top of the generated code. For now I ended up reverting to a402b3a as a lazy workaround.

[CasperN]

Btw would your example work if you created a file, foo.rs with contents

include!(concat!(env!("OUT_DIR"), "/protocol_generated.rs"));

?

[jcrevier]

Btw would your example work if you created a file, foo.rs with contents

include!(concat!(env!("OUT_DIR"), "/protocol_generated.rs"));

?

I'm running into this issue as well. As far as I can tell it doesn't matter if the include! invocation is inside a module in a file, or if the file itself serves as the module.

[nerdrew]

Thoughts on adding a flag to flatc to add the allow statement in the generated rust?