Docs.rs does not compile on nightly since nightly-2024-04-05

[dtolnay]

This is to let you know that docs.rs is impacted by rust-lang/rust#119820, which is an upcoming intentional breaking change in Rust 1.79. There will need to be some code changes in docs.rs before updating to Rust 1.79.

$ cargo +nightly-2024-04-05 check

error: lifetime may not live long enough
  --> src/db/types.rs:4:66
   |
4  | #[derive(Debug, Clone, PartialEq, Eq, Serialize, FromSql, ToSql, sqlx::Type)]
   |                                                                  ^^^^^^^^^^
   |                                                                  |
   |                                                                  lifetime `'r` defined here
   |                                                                  requires that `'r` must outlive `'static`
   |
note: due to current limitations in the borrow checker, this implies a `'static` lifetime
  --> ~/.cargo/registry/src/index.crates.io-6f17d22bba15001f/sqlx-postgres-0.7.4/src/types/record.rs:97:12
   |
97 |         T: for<'a> Decode<'a, Postgres> + Type<Postgres>,
   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   = note: this error originates in the derive macro `sqlx::Type` (in Nightly builds, run with -Z macro-backtrace for more info)

error: implementation of `sqlx::Decode` is not general enough
 --> src/db/types.rs:4:66
  |
4 | #[derive(Debug, Clone, PartialEq, Eq, Serialize, FromSql, ToSql, sqlx::Type)]
  |                                                                  ^^^^^^^^^^ implementation of `sqlx::Decode` is not general enough
  |
  = note: `std::string::String` must implement `sqlx::Decode<'0, Postgres>`, for any lifetime `'0`...
  = note: ...but it actually implements `sqlx::Decode<'1, Postgres>`, for some specific lifetime `'1`
  = note: this error originates in the derive macro `sqlx::Type` (in Nightly builds, run with -Z macro-backtrace for more info)

error: implementation of `sqlx::Decode` is not general enough
 --> src/db/types.rs:4:66
  |
4 | #[derive(Debug, Clone, PartialEq, Eq, Serialize, FromSql, ToSql, sqlx::Type)]
  |                                                                  ^^^^^^^^^^ implementation of `sqlx::Decode` is not general enough
  |
  = note: `Vec<std::string::String>` must implement `sqlx::Decode<'0, Postgres>`, for any lifetime `'0`...
  = note: ...but it actually implements `sqlx::Decode<'1, Postgres>`, for some specific lifetime `'1`
  = note: this error originates in the derive macro `sqlx::Type` (in Nightly builds, run with -Z macro-backtrace for more info)

https://gist.github.com/lcnr/7c1c652f30567048ea240554a36ed95c#httpsgithubcomlaunchbadgesqlx-some-derives-of-sqlxtype has an analysis of how sqlx is involved.

[syphar]

thanks for the ping!

It sounds like we just have to wait for the sqlx release, which I assume would happen before the new stable release?

[dtolnay]

I'm not sure about that. I tried building docs.rs with this change in Cargo.toml:

@@ -40,7 +40,7 @@ semver = { version = "1.0.4", features = ["serde"] }
 r2d2 = "0.8"
 r2d2_postgres = "0.18"
-sqlx = { version = "0.7", features = [ "runtime-tokio", "postgres", "chrono" ] }
+sqlx = { version = "0.8.0-alpha.0", features = [ "runtime-tokio", "postgres", "chrono" ] }
 url = { version = "2.1.1", features = ["serde"] }
 docsrs-metadata = { path = "crates/metadata" }
@@ -68,7 +68,7 @@ zip = {version = "0.6.2", default-features = false, features = ["bzip2"]}
 getrandom = "0.2.1"
 itertools = { version = "0.12.0", optional = true}
-rusqlite = { version = "0.30.0", features = ["bundled"] }
+rusqlite = { version = "0.31.0", features = ["bundled"] }
 hex = "0.4.3"
 
@@ -154,3 +154,6 @@ harness = false
 name = "cratesfyi"
 test = false
 doc = false
+
+[patch.crates-io]
+sqlx = { git = "https://github.com/launchbadge/sqlx" }

and while there are a few "mismatched types" errors in unrelated code from various breaking changes in those crates, I am still seeing all 3 of the original errors above related to sqlx::Type. So there may be more digging for you or @lcnr to do.

[lcnr]

I'll look into this 👍

[lcnr]

It sounds like we just have to wait for the sqlx release, which I assume would happen before the new stable release?

actually no, I messed up while looking at the regression. THis still requires a change to sqlx. Will open a PR and potentially delay the breaking change in rustc by one version to give users more time to update