Build failure with v1.5.2: item not found in TypeParamBound

[nategraf]

Hi team, I use borsh-derive as a dependency in my project and got this build error this morning. I'll get some more information and try to get a smaller reproduction case.

    Compiling borsh-derive v1.5.2
error[E0599]: no variant or associated item named `PreciseCapture` found for enum `TypeParamBound` in the current scope
   --> /home/ubuntu/.cargo/registry/src/index.crates.io-6f17d22bba15001f/borsh-derive-1.5.2/src/internals/generics.rs:264:31
    |
264 |             | TypeParamBound::PreciseCapture(_) => {}
    |                               ^^^^^^^^^^^^^^ variant or associated item not found in `TypeParamBound`

[dj8yfo]

@nategraf well, a cargo update should help.

it got an update in syn from https://docs.rs/syn/2.0.77/syn/enum.TypeParamBound.html to https://docs.rs/syn/2.0.87/syn/enum.TypeParamBound.html.

it should not fail for --locked builds, as borsh version hasn't changed for those as well

but absolutely precisely and technically , yes, it's a omission/bug on borsh's side, so we'll update the precise minimum
required syn version https://github.com/near/borsh-rs/blob/master/borsh-derive/Cargo.toml#L28 and release that as 1.5.3

if something else is limiting the maximum version for syn in your dependency tree to be lower than https://docs.rs/syn/2.0.81/syn/enum.TypeParamBound.html, then cargo update won't help

that can typically be figured out with cargo tree --invert CLI command runs

[nategraf]

Ah thank you. That is helpful. As you indicate, the Cargo.toml currently specifies syn with version = "2". As far as I can tell, it looks like PreciseCapture was introduced with version 2.0.81. With that, it would be good to specify this as the minimum version in your Cargo.toml. I've opened a PR to do so. No worries if this is not the right solution for you.

#320

This also provides enough info for us to work around the issue. We will specify syn = 2.0.81 in our own Cargo.toml for now.