Build failure in model: syn::Item cannot be formatted using {:?}

[badicsalex]

With both the crates.io version and on master, I get the following build error:

error[E0277]: `syn::Item` doesn't implement `std::fmt::Debug`
   --> /home/alex/.cargo/git/checkouts/asn1rs-f6cc173094da5683/b189ef6/asn1rs-model/src/ast/mod.rs:117:40
    |
117 |         println!("Matching item {:?}", item);
    |                                        ^^^^ `syn::Item` cannot be formatted using `{:?}` because it doesn't implement `std::fmt::Debug`
    |
    = help: the trait `std::fmt::Debug` is not implemented for `syn::Item`
    = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)

I guess the problem is that if cfg! is a runtime gate, and the gated code still has to build. And maybe the fact that the build now uses syn v1.0.109. The Debug trait for syn's Item can be enabled with the extra-traits feature flag.

(P.S.: Great work with the decoder, I'm also using it to decode v1.4.1 CAMs :) It works well once I get it to build.)

[kellerkindt]

Hi there, in which configuration do you use asn1rs? I can't get it to fail.

cargo build -p asn1rs --features debug-proc-macro
...
   Compiling syn v1.0.109
   Compiling syn v2.0.13
...
    Finished dev [unoptimized + debuginfo] target(s) in 21.33s

Could you provide an MVP?

[badicsalex]

I just made a new project with cargo new, put this line into Cargo.toml:

[dependencies]
asn1rs =  { git = "https://github.com/kellerkindt/asn1rs.git", rev = "b189ef6"}

And got the same error.

I'm using rustc 1.68.0.

Cargo.lock looks like this with the repro:

Click to show

# This file is automatically @generated by Cargo. # It is not intended for manual editing. version = 3

[[package]]
name = "addr2line"
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dependencies = [
"gimli",
]

[[package]]
name = "adler"
version = "1.0.2"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"

[[package]]
name = "ansi_term"
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source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "d52a9bb7ec0cf484c551830a7ce27bd20d67eac647e1befb56b0be4ee39a55d2"
dependencies = [
"winapi",
]

[[package]]
name = "asn1rs"
version = "0.2.2"
source = "git+https://github.com/kellerkindt/asn1rs.git?rev=b189ef6#b189ef676000e7319b16bebb7c693296631b2d60"
dependencies = [
"asn1rs-macros",
"asn1rs-model",
"backtrace",
"byteorder",
"clap",
"codegen",
"serde",
"serde_derive",
]

[[package]]
name = "asn1rs-macros"
version = "0.2.2"
source = "git+https://github.com/kellerkindt/asn1rs.git?rev=b189ef6#b189ef676000e7319b16bebb7c693296631b2d60"
dependencies = [
"asn1rs-model",
"quote",
"syn 1.0.109",
]

[[package]]
name = "asn1rs-model"
version = "0.2.2"
source = "git+https://github.com/kellerkindt/asn1rs.git?rev=b189ef6#b189ef676000e7319b16bebb7c693296631b2d60"
dependencies = [
"backtrace",
"codegen",
"proc-macro2",
"quote",
"strum",
"strum_macros",
"syn 1.0.109",
]

[[package]]
name = "asn1test"
version = "0.1.0"
dependencies = [
"asn1rs",
]

[[package]]
name = "atty"
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source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
dependencies = [
"hermit-abi",
"libc",
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]

[[package]]
name = "autocfg"
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[[package]]
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"libc",
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"object",
"rustc-demangle",
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[[package]]
name = "bitflags"
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[[package]]
name = "byteorder"
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[[package]]
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[[package]]
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[[package]]
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[[package]]
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[[package]]
name = "gimli"
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source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "ad0a93d233ebf96623465aad4046a8d3aa4da22d4f4beba5388838c8a434bbb4"

[[package]]
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[[package]]
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[[package]]
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[[package]]
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[[package]]
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[[package]]
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[[package]]
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[[package]]
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[[package]]
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[kellerkindt]

Interesting ... why does the CI not fail? ... Hopefully fixed by 5b8c49f ?

[badicsalex]

I wonder why asn1rs even builds when built from its own directory. Apparently strum_macros v0.19.4 enables the extra-traits feature on syn, but I have no idea how that fixes the build. Maybe it's a compilation unit thing.

[kellerkindt]

Thanks for reporting, anyway!

[kellerkindt]

Could you please confirm that this is fixed now?

[badicsalex]

Yup, it works now. Thanks for the speedy response.