Fix #3748

.github/workflows/ci.yml

@@ -221,7 +221,7 @@ jobs:
       - name: Test diesel-derives (nightly)
         if: matrix.rust == 'nightly'
         shell: bash
-        run: cargo +${{ matrix.rust }} test --manifest-path diesel_derives/Cargo.toml --no-default-features --features "diesel/${{ matrix.backend }} diesel/unstable"
+        run: cargo +${{ matrix.rust }} test --manifest-path diesel_derives/Cargo.toml --no-default-features --features "diesel/${{ matrix.backend }} diesel/unstable diesel/time time diesel/chrono chrono"
 
       - name: Test diesel-derives
         shell: bash

diesel/Cargo.toml

@@ -68,6 +68,8 @@ 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"]
 
 [package.metadata.docs.rs]
 features = ["postgres", "mysql", "sqlite", "extras"]

diesel/src/internal/derives.rs

@@ -69,4 +69,12 @@ pub mod multiconnection {
 
     #[doc(hidden)]
     pub use crate::query_builder::select_statement::SelectStatementAccessor;
+
+    #[doc(hidden)]
+    #[cfg(feature = "chrono")]
+    pub use chrono;
+
+    #[doc(hidden)]
+    #[cfg(feature = "time")]
+    pub use time;
 }

diesel_derives/Cargo.toml

@@ -44,3 +44,5 @@ mysql = []
 without-deprecated = []
 with-deprecated = []
 r2d2 = []
+chrono = []
+time = []

diesel_derives/src/multiconnection.rs

@@ -565,7 +565,7 @@ fn generate_row(connection_types: &[ConnectionVariant]) -> TokenStream {
 }
 
 fn generate_bind_collector(connection_types: &[ConnectionVariant]) -> TokenStream {
-    let to_sql_impls = vec![
+    let mut to_sql_impls = vec![
         (
             quote::quote!(diesel::sql_types::SmallInt),
             quote::quote!(i16),
@@ -583,11 +583,40 @@ fn generate_bind_collector(connection_types: &[ConnectionVariant]) -> TokenStrea
             quote::quote!([u8]),
         ),
         (quote::quote!(diesel::sql_types::Bool), quote::quote!(bool)),
-    ]
-    .into_iter()
-    .map(|t| generate_to_sql_impls(t, connection_types));
+    ];
+    if cfg!(feature = "chrono") {
+        to_sql_impls.push((
+            quote::quote!(diesel::sql_types::Timestamp),
+            quote::quote!(diesel::internal::derives::multiconnection::chrono::NaiveDateTime),
+        ));
+        to_sql_impls.push((
+            quote::quote!(diesel::sql_types::Date),
+            quote::quote!(diesel::internal::derives::multiconnection::chrono::NaiveDate),
+        ));
+        to_sql_impls.push((
+            quote::quote!(diesel::sql_types::Time),
+            quote::quote!(diesel::internal::derives::multiconnection::chrono::NaiveTime),
+        ));
+    }
+    if cfg!(feature = "time") {
+        to_sql_impls.push((
+            quote::quote!(diesel::sql_types::Timestamp),
+            quote::quote!(diesel::internal::derives::multiconnection::time::PrimitiveDateTime),
+        ));
+        to_sql_impls.push((
+            quote::quote!(diesel::sql_types::Time),
+            quote::quote!(diesel::internal::derives::multiconnection::time::Time),
+        ));
+        to_sql_impls.push((
+            quote::quote!(diesel::sql_types::Date),
+            quote::quote!(diesel::internal::derives::multiconnection::time::Date),
+        ));
+    }
+    let to_sql_impls = to_sql_impls
+        .into_iter()
+        .map(|t| generate_to_sql_impls(t, connection_types));
 
-    let from_sql_impls = vec![
+    let mut from_sql_impls = vec![
         (
             quote::quote!(diesel::sql_types::SmallInt),
             quote::quote!(i16),
@@ -608,9 +637,36 @@ fn generate_bind_collector(connection_types: &[ConnectionVariant]) -> TokenStrea
             quote::quote!(Vec<u8>),
         ),
         (quote::quote!(diesel::sql_types::Bool), quote::quote!(bool)),
-    ]
-    .into_iter()
-    .map(generate_from_sql_impls);
+    ];
+    if cfg!(feature = "chrono") {
+        from_sql_impls.push((
+            quote::quote!(diesel::sql_types::Timestamp),
+            quote::quote!(diesel::internal::derives::multiconnection::chrono::NaiveDateTime),
+        ));
+        from_sql_impls.push((
+            quote::quote!(diesel::sql_types::Date),
+            quote::quote!(diesel::internal::derives::multiconnection::chrono::NaiveDate),
+        ));
+        from_sql_impls.push((
+            quote::quote!(diesel::sql_types::Time),
+            quote::quote!(diesel::internal::derives::multiconnection::chrono::NaiveTime),
+        ));
+    }
+    if cfg!(feature = "time") {
+        from_sql_impls.push((
+            quote::quote!(diesel::sql_types::Timestamp),
+            quote::quote!(diesel::internal::derives::multiconnection::time::PrimitiveDateTime),
+        ));
+        from_sql_impls.push((
+            quote::quote!(diesel::sql_types::Time),
+            quote::quote!(diesel::internal::derives::multiconnection::time::Time),
+        ));
+        from_sql_impls.push((
+            quote::quote!(diesel::sql_types::Date),
+            quote::quote!(diesel::internal::derives::multiconnection::time::Date),
+        ));
+    }
+    let from_sql_impls = from_sql_impls.into_iter().map(generate_from_sql_impls);
 
     let into_bind_value_bounds = connection_types.iter().map(|c| {
         let ty = c.ty;