Merge pull request diesel-rs#4008 from weiznich/bump/1.78

Bump toolchain version to 1.78

.github/workflows/ci.yml

@@ -324,7 +324,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@master
         with:
-          toolchain: nightly-2024-01-15
+          toolchain: stable
       - name: Cache cargo registry
         uses: Swatinem/rust-cache@v2
         with:
@@ -337,7 +337,7 @@ jobs:
 
       - name: Run compile tests
         shell: bash
-        run: cargo +nightly-2024-01-15  test --manifest-path diesel_compile_tests/Cargo.toml
+        run: cargo +stable  test --manifest-path diesel_compile_tests/Cargo.toml
 
   rustfmt_and_clippy:
     name: Check rustfmt style && run clippy
@@ -486,11 +486,11 @@ jobs:
         run: cargo +nightly -Z build-std test --manifest-path diesel/Cargo.toml --no-default-features --features "postgres pq-sys pq-sys/bundled pq-src/with-asan" --target x86_64-unknown-linux-gnu
 
   minimal_rust_version:
-    name: Check Minimal supported rust version (1.75.0)
+    name: Check Minimal supported rust version (1.78.0)
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@1.75.0
+      - uses: dtolnay/rust-toolchain@1.78.0
       - uses: dtolnay/rust-toolchain@nightly
       - uses: taiki-e/install-action@cargo-hack
       - uses: taiki-e/install-action@cargo-minimal-versions
@@ -503,15 +503,15 @@ jobs:
           sudo apt-get update
           sudo apt-get -y install libsqlite3-dev libpq-dev libmysqlclient-dev
       - name: Check diesel_derives
-        run: cargo +1.75.0 minimal-versions check -p diesel_derives --features "postgres sqlite mysql 32-column-tables 64-column-tables 128-column-tables without-deprecated with-deprecated r2d2"
+        run: cargo +1.78.0 minimal-versions check -p diesel_derives --features "postgres sqlite mysql 32-column-tables 64-column-tables 128-column-tables without-deprecated with-deprecated r2d2"
       - name: Check diesel
-        run: cargo +1.75.0 minimal-versions check -p diesel --features "postgres mysql sqlite extras"
+        run: cargo +1.78.0 minimal-versions check -p diesel --features "postgres mysql sqlite extras"
       - name: Check diesel_dynamic_schema
-        run: cargo +1.75.0 minimal-versions check -p diesel-dynamic-schema --all-features
+        run: cargo +1.78.0 minimal-versions check -p diesel-dynamic-schema --all-features
       - name: Check diesel_migrations
-        run: cargo +1.75.0 minimal-versions check -p diesel_migrations --all-features
+        run: cargo +1.78.0 minimal-versions check -p diesel_migrations --all-features
       - name: Check diesel_cli
-        run: cargo +1.75.0 minimal-versions check -p diesel_cli --features "default sqlite-bundled"
+        run: cargo +1.78.0 minimal-versions check -p diesel_cli --features "default sqlite-bundled"
 
   typos:
     name: Spell Check with Typos

CHANGELOG.md

@@ -25,7 +25,7 @@ Increasing the minimal supported Rust version will always be coupled at least wi
 
 ### Changed
 
-* The minimal officially supported rustc version is now 1.75.0
+* The minimal officially supported rustc version is now 1.78.0
 * Deprecated `sql_function!` in favour of `define_sql_function!` which provides compatibility with `#[dsl::auto_type]`
 
 ## [2.1.0] 2023-05-26

Cargo.toml

@@ -31,7 +31,7 @@ members = [
 ]
 
 [workspace.package]
-rust-version = "1.75.0"
+rust-version = "1.78.0"
 
 # Config for 'cargo dist'
 [workspace.metadata.dist]

diesel/Cargo.toml

@@ -67,7 +67,6 @@ postgres_backend = ["diesel_derives/postgres", "bitflags", "byteorder", "itoa"]
 mysql_backend = ["diesel_derives/mysql", "byteorder"]
 returning_clauses_for_sqlite_3_35 = []
 i-implement-a-third-party-backend-and-opt-into-breaking-changes = []
-nightly-error-messages = []
 r2d2 = ["diesel_derives/r2d2", "dep:r2d2"]
 chrono = ["diesel_derives/chrono", "dep:chrono"]
 time = ["diesel_derives/time", "dep:time"]

diesel/src/deserialize.rs

@@ -418,12 +418,9 @@ pub use diesel_derives::QueryableByName;
 ///     }
 /// }
 /// ```
-#[cfg_attr(
-    feature = "nightly-error-messages",
-    diagnostic::on_unimplemented(
-        message = "Cannot deserialize a value of the database type `{A}` as `{Self}`",
-        note = "Double check your type mappings via the documentation of `{A}`"
-    )
+#[diagnostic::on_unimplemented(
+    message = "cannot deserialize a value of the database type `{A}` as `{Self}`",
+    note = "double check your type mappings via the documentation of `{A}`"
 )]
 pub trait FromSql<A, DB: Backend>: Sized {
     /// See the trait documentation.
@@ -451,12 +448,10 @@ pub trait FromSql<A, DB: Backend>: Sized {
 /// that implement one of the following traits:
 ///    * [`Queryable`]
 ///    * [`QueryableByName`]
-#[cfg_attr(
-    feature = "nightly-error-messages",
-    diagnostic::on_unimplemented(
-        note = "`diesel::sql_query` requires the loading target to column names for loading values.\n\
-                 You need to provide a type that explicitly derives `diesel::deserialize::QueryableByName`",
-    )
+#[diagnostic::on_unimplemented(
+    note = "double check your type mappings via the documentation of `{ST}`",
+    note = "`diesel::sql_query` requires the loading target to column names for loading values.\n\
+             You need to provide a type that explicitly derives `diesel::deserialize::QueryableByName`"
 )]
 pub trait FromSqlRow<ST, DB: Backend>: Sized {
     /// See the trait documentation.

diesel/src/expression/mod.rs

@@ -318,12 +318,9 @@ where
 /// Notably, columns will not implement this trait for the right side of a left
 /// join. To select a column or expression using a column from the right side of
 /// a left join, you must call `.nullable()` on it.
-#[cfg_attr(
-    feature = "nightly-error-messages",
-    diagnostic::on_unimplemented(
-        message = "Cannot select `{Self}` from `{QS}`",
-        note = "`{Self}` is no valid selection for `{QS}`"
-    )
+#[diagnostic::on_unimplemented(
+    message = "Cannot select `{Self}` from `{QS}`",
+    note = "`{Self}` is no valid selection for `{QS}`"
 )]
 pub trait SelectableExpression<QS: ?Sized>: AppearsOnTable<QS> {}
 

diesel/src/expression/operators.rs

@@ -744,6 +744,18 @@ where
     }
 }
 
+#[diagnostic::on_unimplemented(
+    message = "Cannot use the `LIKE` operator with expressions of the type `{ST}` for the backend `{Self}`",
+    note = "Expressions of the type `diesel::sql_types::Text` and `diesel::sql_types::Nullable<Text>` are \n\
+            allowed for all backends"
+)]
+#[cfg_attr(
+    feature = "postgres_backend",
+    diagnostic::on_unimplemented(
+        note = "Expressions of the type `diesel::sql_types::Binary` and `diesel::sql_types::Nullable<Binary>` are \n\
+            allowed for the PostgreSQL backend"
+    )
+)]
 pub trait LikeIsAllowedForType<ST>: Backend {}
 
 impl<DB> LikeIsAllowedForType<crate::sql_types::Text> for DB where DB: Backend {}

diesel/src/lib.rs

@@ -94,9 +94,6 @@
 //! by rustc, including the `required because of …` part of the message.
 //! Your IDE might hide important parts!
 //!
-//! If you use a nightly compiler you might want to enable the `nightly-error-messages`
-//! feature flag to automatically improve some error messages.
-//!
 //! The following error messages are common:
 //!
 //! * `the trait bound (diesel::sql_types::Integer, …, diesel::sql_types::Text): load_dsl::private::CompatibleType<YourModel, Pg> is not satisfied`
@@ -212,18 +209,12 @@
 //! explicitly opts out the stability guarantee given by diesel. This feature overrides the `with-deprecated`.
 //! Note that this may also remove items that are not shown as `#[deprecated]` in our documentation, due to
 //! various bugs in rustdoc. It can be used to check if you depend on any such hidden `#[deprecated]` item.
-//! - `nightly-error-messages`: This feature enables the generation of improved compiler error messages for
-//! common mistakes using diesel. This feature requires a nightly rust compiler and is considered to be unstable.
-//! It requires adding `#![feature(diagnostic_namespace)]` to your crate.
-//! We might remove it in future diesel versions without replacement or deprecation.
-//!
 //!
 //! By default the following features are enabled:
 //!
 //! - `with-deprecated`
 //! - `32-column-tables`
 
-#![cfg_attr(feature = "nightly-error-messages", feature(diagnostic_namespace))]
 #![cfg_attr(feature = "unstable", feature(trait_alias))]
 #![cfg_attr(doc_cfg, feature(doc_cfg, doc_auto_cfg))]
 #![cfg_attr(feature = "128-column-tables", recursion_limit = "256")]

diesel/src/mysql/connection/url.rs

@@ -71,7 +71,7 @@ impl ConnectionOptions {
         }
 
         let query_pairs = url.query_pairs().into_owned().collect::<HashMap<_, _>>();
-        if query_pairs.get("database").is_some() {
+        if query_pairs.contains_key("database") {
             return Err(connection_url_error());
         }
 

diesel/src/pg/expression/expression_methods.rs

@@ -2406,12 +2406,20 @@ pub(in crate::pg) mod private {
     /// Marker trait used to implement `ArrayExpressionMethods` on the appropriate
     /// types. Once coherence takes associated types into account, we can remove
     /// this trait.
+    #[diagnostic::on_unimplemented(
+        message = "`{Self}` is neither `diesel::sql_types::Array<_>` nor `diesel::sql_types::Nullable<Array<_>>`",
+        note = "try to provide an expression that produces one of the expected sql types"
+    )]
     pub trait ArrayOrNullableArray {}
 
     impl<T> ArrayOrNullableArray for Array<T> {}
     impl<T> ArrayOrNullableArray for Nullable<Array<T>> {}
 
     /// Marker trait used to implement `PgNetExpressionMethods` on the appropriate types.
+    #[diagnostic::on_unimplemented(
+        message = "`{Self}` is neither `diesel::sql_types::Inet`, `diesel::sql_types::Cidr`, `diesel::sql_types::Nullable<Inet>` nor `diesel::sql_types::Nullable<Cidr>",
+        note = "try to provide an expression that produces one of the expected sql types"
+    )]
     pub trait InetOrCidr {}
 
     impl InetOrCidr for Inet {}
@@ -2422,6 +2430,10 @@ pub(in crate::pg) mod private {
     /// Marker trait used to implement `PgTextExpressionMethods` on the appropriate
     /// types. Once coherence takes associated types into account, we can remove
     /// this trait.
+    #[diagnostic::on_unimplemented(
+        message = "`{Self}` is neither `diesel::sql_types::Text` nor `diesel::sql_types::Nullable<Text>`",
+        note = "try to provide an expression that produces one of the expected sql types"
+    )]
     pub trait TextOrNullableText {}
 
     impl TextOrNullableText for Text {}
@@ -2443,12 +2455,20 @@ pub(in crate::pg) mod private {
     /// Marker trait used to implement `PgRangeExpressionMethods` on the appropriate
     /// types. Once coherence takes associated types into account, we can remove
     /// this trait.
+    #[diagnostic::on_unimplemented(
+        message = "`{Self}` is neither `diesel::sql_types::Range<_>` nor `diesel::sql_types::Nullable<Range<_>>`",
+        note = "try to provide an expression that produces one of the expected sql types"
+    )]
     pub trait RangeOrNullableRange {}
 
     impl<ST> RangeOrNullableRange for Range<ST> {}
     impl<ST> RangeOrNullableRange for Nullable<Range<ST>> {}
 
     /// Marker trait used to implement `PgJsonbExpressionMethods` on the appropriate types.
+    #[diagnostic::on_unimplemented(
+        message = "`{Self}` is neither `diesel::sql_types::Jsonb` nor `diesel::sql_types::Nullable<Jsonb>`",
+        note = "try to provide an expression that produces one of the expected sql types"
+    )]
     pub trait JsonbOrNullableJsonb {}
 
     impl JsonbOrNullableJsonb for Jsonb {}
@@ -2523,13 +2543,21 @@ pub(in crate::pg) mod private {
         }
     }
 
+    #[diagnostic::on_unimplemented(
+        message = "`{Self}` is neither `diesel::sql_types::Text`, `diesel::sql_types::Integer` nor `diesel::sql_types::Array<Text>`",
+        note = "try to provide an expression that produces one of the expected sql types"
+    )]
     pub trait TextArrayOrTextOrInteger {}
 
     impl TextArrayOrTextOrInteger for Array<Text> {}
     impl TextArrayOrTextOrInteger for Text {}
     impl TextArrayOrTextOrInteger for Integer {}
 
     /// Marker trait used to implement `PgAnyJsonExpressionMethods` on the appropriate types.
+    #[diagnostic::on_unimplemented(
+        message = "`{Self}` is neither `diesel::sql_types::Json`, `diesel::sql_types::Jsonb`, `diesel::sql_types::Nullable<Json>` nor `diesel::sql_types::Nullable<Jsonb>`",
+        note = "try to provide an expression that produces one of the expected sql types"
+    )]
     pub trait JsonOrNullableJsonOrJsonbOrNullableJsonb {}
     impl JsonOrNullableJsonOrJsonbOrNullableJsonb for Json {}
     impl JsonOrNullableJsonOrJsonbOrNullableJsonb for Nullable<Json> {}
@@ -2578,10 +2606,18 @@ pub(in crate::pg) mod private {
         }
     }
 
+    #[diagnostic::on_unimplemented(
+        message = "`{Self}` is neither `diesel::sql_types::Text` nor `diesel::sql_types::Integer`",
+        note = "try to provide an expression that produces one of the expected sql types"
+    )]
     pub trait TextOrInteger {}
     impl TextOrInteger for Text {}
     impl TextOrInteger for Integer {}
 
+    #[diagnostic::on_unimplemented(
+        message = "`{Self}` is neither `diesel::sql_types::Binary` nor `diesel::sql_types::Nullable<Binary>`",
+        note = "try to provide an expression that produces one of the expected sql types"
+    )]
     pub trait BinaryOrNullableBinary {}
 
     impl BinaryOrNullableBinary for Binary {}

diesel/src/query_builder/mod.rs

@@ -210,6 +210,11 @@ pub trait SelectQuery {
 ///
 /// [`ExecuteDsl`]: crate::query_dsl::methods::ExecuteDsl
 /// [`LoadQuery`]: crate::query_dsl::methods::LoadQuery
+#[diagnostic::on_unimplemented(
+    message = "`{Self}` is no valid SQL fragment for the `{DB}` backend",
+    note = "this usually means that the `{DB}` database system does not support \n\
+            this SQL syntax"
+)]
 pub trait QueryFragment<DB: Backend, SP = self::private::NotSpecialized> {
     /// Walk over this `QueryFragment` for all passes.
     ///

diesel/src/query_dsl/load_dsl.rs

@@ -179,13 +179,11 @@ mod private {
         doc_cfg,
         doc(cfg(feature = "i-implement-a-third-party-backend-and-opt-into-breaking-changes"))
     )]
-    #[cfg_attr(
-        feature = "nightly-error-messages",
-        diagnostic::on_unimplemented(
-            note = "This is a mismatch between what your query returns and what your type expects the query to return\n\
-                Consider using `#[derive(Selectable)]` + `#[diesel(check_for_backend({DB}))]` on your struct `{U}` and \n\
-                in your query `.select({U}::as_select())` to get a better error message",
-        )
+    #[diagnostic::on_unimplemented(
+        note = "this is a mismatch between what your query returns and what your type expects the query to return",
+        note = "the fields in your struct need to match the fields returned by your query in count, order and type",
+        note = "consider using `#[derive(Selectable)]` + `#[diesel(check_for_backend({DB}))]` on your struct `{U}` and \n\
+                in your query `.select({U}::as_select())` to get a better error message"
     )]
     pub trait CompatibleType<U, DB> {
         type SqlType;

diesel/src/query_source/mod.rs

@@ -96,6 +96,10 @@ pub trait AppearsInFromClause<QS> {
 ///   (no call to [`allow_tables_to_appear_in_same_query!`] was made)
 /// - You are attempting to use two aliases to the same table in the same query, but they
 ///   were declared through different calls to [`alias!`](crate::alias)
+#[diagnostic::on_unimplemented(
+    note = "double check that `{T}` and `{Self}` appear in the same `allow_tables_to_appear_in_same_query!` \ncall if both are tables",
+    note = "double check that `{T}` and `{Self}` appear in the same `alias!` call if both \nare aliases to the same table"
+)]
 pub trait TableNotEqual<T: Table>: Table {}
 
 impl<T1, T2> AppearsInFromClause<T2> for T1

diesel/src/sql_types/mod.rs

@@ -656,6 +656,10 @@ pub mod is_nullable {
 
 /// A marker trait for accepting expressions of the type `Bool` and
 /// `Nullable<Bool>` in the same place
+#[diagnostic::on_unimplemented(
+    message = "`{Self}` is neither `diesel::sql_types::Bool` nor `diesel::sql_types::Nullable<Bool>`",
+    note = "try to provide an expression that produces one of the expected sql types"
+)]
 pub trait BoolOrNullableBool {}
 
 impl BoolOrNullableBool for Bool {}

diesel/src/sql_types/ord.rs

@@ -1,6 +1,9 @@
 use crate::sql_types::{self, is_nullable, SqlType};
 
 /// Marker trait for types which can be used with `MAX` and `MIN`
+#[diagnostic::on_unimplemented(
+    message = "expressions of the type `{Self}` cannot be ordered by the database"
+)]
 pub trait SqlOrd: SqlType {}
 
 impl SqlOrd for sql_types::SmallInt {}