doc-tests don't work with macros 1.1

[colin-kiegel]

It looks like having proc-macro = true in Cargo.toml disables all doc-tests. However unit tests #[test] work fine.

Steps to reproduce

1. cargo new foo

2. edit Cargo.toml

# ... the usual
[lib]
proc-macro = true

3. edit src/lib.rs

//! ```rust
//! fn main() { panic!() } /* <-- this test should fail */
//! ```

#![crate_type = "proc-macro"]
extern crate proc_macro;

#[proc_macro_derive(Foo)]
pub fn derive(_: proc_macro::TokenStream) -> proc_macro::TokenStream {
    unimplemented!()
}

4. cargo test

running 0 tests

test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured

[colin-kiegel]

just linking related tickets to attract some more attention :-)

• Tracking issue for "Macros 1.1" (RFC 1681) Tracking issue for "Macros 1.1" (RFC #1681) #35900
• Allow --test to be used on proc-macro crates Allow --test to be used on proc-macro crates #38107
• 'cargo test' with proc_macro_derive fails 'cargo test' with proc_macro_derive fails #37480

[sanmai-NL]

@colin-kiegel: I think this should be filed at rust-lang/cargo, no?

[colin-kiegel]

ok, I filed it there too: rust-lang/cargo#3545

I'm not sure if this ticket belongs here or with cargo, so I'll leave it to someone else to close one of these tickets.

[keeperofdakeys]

I'll take a look at this, it's most likely a rust bug. There is probably a codepath that isn't visited because it's a proc macro crate.

[keeperofdakeys]

From what I can see, this is both a rust bug and a cargo bug. On a proc macro crate, cargo doesn't call rustdoc --test, and rustdoc --test doesn't actually work on proc macro crates. Both should be simple to fix though.