Fix span in proc macro

diesel_compile_tests/tests/fail/derive/bad_insertable.stderr

@@ -79,6 +79,9 @@ error[E0277]: the trait bound `i32: diesel::Expression` is not satisfied
 error[E0277]: the trait bound `std::string::String: diesel::Expression` is not satisfied
   --> tests/fail/derive/bad_insertable.rs:12:5
    |
+10 | #[derive(Insertable)]
+   |          ---------- in this derive macro expansion
+11 | struct User {
 12 |     id: String,
    |     ^^ the trait `diesel::Expression` is not implemented for `std::string::String`, which is required by `std::string::String: AsExpression<diesel::sql_types::Integer>`
    |
@@ -93,10 +96,14 @@ error[E0277]: the trait bound `std::string::String: diesel::Expression` is not s
              (T0, T1, T2, T3, T4, T5, T6, T7)
            and $N others
    = note: required for `std::string::String` to implement `AsExpression<diesel::sql_types::Integer>`
+   = note: this error originates in the derive macro `Insertable` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0277]: the trait bound `i32: diesel::Expression` is not satisfied
   --> tests/fail/derive/bad_insertable.rs:13:5
    |
+10 | #[derive(Insertable)]
+   |          ---------- in this derive macro expansion
+...
 13 |     name: i32,
    |     ^^^^ the trait `diesel::Expression` is not implemented for `i32`, which is required by `i32: AsExpression<diesel::sql_types::Text>`
    |
@@ -111,10 +118,14 @@ error[E0277]: the trait bound `i32: diesel::Expression` is not satisfied
              (T0, T1, T2, T3, T4, T5, T6, T7)
            and $N others
    = note: required for `i32` to implement `AsExpression<diesel::sql_types::Text>`
+   = note: this error originates in the derive macro `Insertable` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0277]: the trait bound `std::string::String: diesel::Expression` is not satisfied
   --> tests/fail/derive/bad_insertable.rs:12:5
    |
+10 | #[derive(Insertable)]
+   |          ---------- in this derive macro expansion
+11 | struct User {
 12 |     id: String,
    |     ^^ the trait `diesel::Expression` is not implemented for `std::string::String`, which is required by `&'insert std::string::String: AsExpression<diesel::sql_types::Integer>`
    |
@@ -130,10 +141,14 @@ error[E0277]: the trait bound `std::string::String: diesel::Expression` is not s
            and $N others
    = note: required for `&'insert std::string::String` to implement `diesel::Expression`
    = note: required for `&'insert std::string::String` to implement `AsExpression<diesel::sql_types::Integer>`
+   = note: this error originates in the derive macro `Insertable` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0277]: the trait bound `i32: diesel::Expression` is not satisfied
   --> tests/fail/derive/bad_insertable.rs:13:5
    |
+10 | #[derive(Insertable)]
+   |          ---------- in this derive macro expansion
+...
 13 |     name: i32,
    |     ^^^^ the trait `diesel::Expression` is not implemented for `i32`, which is required by `&'insert i32: AsExpression<diesel::sql_types::Text>`
    |
@@ -149,3 +164,4 @@ error[E0277]: the trait bound `i32: diesel::Expression` is not satisfied
            and $N others
    = note: required for `&'insert i32` to implement `diesel::Expression`
    = note: required for `&'insert i32` to implement `AsExpression<diesel::sql_types::Text>`
+   = note: this error originates in the derive macro `Insertable` (in Nightly builds, run with -Z macro-backtrace for more info)

diesel_derives/src/as_changeset.rs

@@ -1,4 +1,4 @@
-use proc_macro2::TokenStream;
+use proc_macro2::{Span, TokenStream};
 use quote::{quote, quote_spanned};
 use syn::spanned::Spanned as _;
 use syn::{parse_quote, DeriveInput, Expr, Path, Result, Type};
@@ -172,7 +172,7 @@ pub fn derive(item: DeriveInput) -> Result<TokenStream> {
 
 fn field_changeset_ty_embed(field: &Field, lifetime: Option<TokenStream>) -> TokenStream {
     let field_ty = &field.ty;
-    let span = field.span;
+    let span = Span::mixed_site().located_at(field.span);
     quote_spanned!(span=> #lifetime #field_ty)
 }
 

diesel_derives/src/field.rs

@@ -1,6 +1,7 @@
-use proc_macro2::{Span, TokenStream};
-use syn::spanned::Spanned;
-use syn::{Expr, Field as SynField, Ident, Index, Result, Type};
+use {
+    proc_macro2::{Span, TokenStream},
+    syn::{spanned::Spanned, Expr, Field as SynField, Ident, Index, Result, Type},
+};
 
 use crate::attrs::{parse_attributes, AttributeSpanWrapper, FieldAttr, SqlIdentifier};
 
@@ -119,10 +120,10 @@ impl Field {
             None => FieldName::Unnamed(index.into()),
         };
 
-        let span = match name {
+        let span = Span::mixed_site().located_at(match name {
             FieldName::Named(ref ident) => ident.span(),
             FieldName::Unnamed(_) => ty.span(),
-        };
+        });
 
         Ok(Self {
             ty: ty.clone(),

diesel_derives/src/insertable.rs

@@ -2,7 +2,7 @@ use crate::attrs::AttributeSpanWrapper;
 use crate::field::Field;
 use crate::model::Model;
 use crate::util::{inner_of_option_ty, is_option_ty, wrap_in_dummy_mod};
-use proc_macro2::TokenStream;
+use proc_macro2::{Span, TokenStream};
 use quote::quote;
 use quote::quote_spanned;
 use syn::parse_quote;
@@ -177,7 +177,7 @@ fn derive_into_single_table(
 
 fn field_ty_embed(field: &Field, lifetime: Option<TokenStream>) -> TokenStream {
     let field_ty = &field.ty;
-    let span = field.span;
+    let span = Span::mixed_site().located_at(field.span);
     quote_spanned!(span=> #lifetime #field_ty)
 }
 
@@ -193,7 +193,7 @@ fn field_ty_serialize_as(
     treat_none_as_default_value: bool,
 ) -> Result<TokenStream> {
     let column_name = field.column_name()?.to_ident()?;
-    let span = field.span;
+    let span = Span::mixed_site().located_at(field.span);
     if treat_none_as_default_value {
         let inner_ty = inner_of_option_ty(ty);
 
@@ -242,7 +242,7 @@ fn field_ty(
     treat_none_as_default_value: bool,
 ) -> Result<TokenStream> {
     let column_name = field.column_name()?.to_ident()?;
-    let span = field.span;
+    let span = Span::mixed_site().located_at(field.span);
     if treat_none_as_default_value {
         let inner_ty = inner_of_option_ty(&field.ty);
 

diesel_derives/src/queryable_by_name.rs

@@ -1,11 +1,15 @@
-use proc_macro2::TokenStream;
-use quote::quote;
-use syn::{parse_quote, parse_quote_spanned, DeriveInput, Ident, LitStr, Result, Type};
+use {
+    proc_macro2::{Span, TokenStream},
+    quote::quote,
+    syn::{parse_quote, parse_quote_spanned, DeriveInput, Ident, LitStr, Result, Type},
+};
 
-use crate::attrs::AttributeSpanWrapper;
-use crate::field::{Field, FieldName};
-use crate::model::Model;
-use crate::util::wrap_in_dummy_mod;
+use crate::{
+    attrs::AttributeSpanWrapper,
+    field::{Field, FieldName},
+    model::Model,
+    util::wrap_in_dummy_mod,
+};
 
 pub fn derive(item: DeriveInput) -> Result<TokenStream> {
     let model = Model::from_item(&item, false, false)?;
@@ -45,7 +49,7 @@ pub fn derive(item: DeriveInput) -> Result<TokenStream> {
 
     for field in model.fields() {
         let where_clause = generics.where_clause.get_or_insert(parse_quote!(where));
-        let span = field.span;
+        let span = Span::mixed_site().located_at(field.span);
         let field_ty = field.ty_for_deserialize();
         if field.embed() {
             where_clause
@@ -63,7 +67,7 @@ pub fn derive(item: DeriveInput) -> Result<TokenStream> {
         let field_check_bound = model.fields().iter().filter(|f| !f.embed()).flat_map(|f| {
             backends.iter().map(move |b| {
                 let field_ty = f.ty_for_deserialize();
-                let span = f.span;
+                let span = Span::mixed_site().located_at(f.span);
                 let ty = sql_type(f, model).unwrap();
                 quote::quote_spanned! {span =>
                     #field_ty: diesel::deserialize::FromSqlRow<#ty, #b>

diesel_derives/src/selectable.rs

@@ -1,12 +1,10 @@
-use proc_macro2::TokenStream;
-use quote::quote;
-use syn::spanned::Spanned;
-use syn::DeriveInput;
-use syn::{parse_quote, Result};
+use {
+    proc_macro2::{Span, TokenStream},
+    quote::quote,
+    syn::{parse_quote, spanned::Spanned, DeriveInput, Result},
+};
 
-use crate::field::Field;
-use crate::model::Model;
-use crate::util::wrap_in_dummy_mod;
+use crate::{field::Field, model::Model, util::wrap_in_dummy_mod};
 
 pub fn derive(item: DeriveInput) -> Result<TokenStream> {
     let model = Model::from_item(&item, false, false)?;
@@ -51,7 +49,7 @@ pub fn derive(item: DeriveInput) -> Result<TokenStream> {
             .filter(|(f, _)| !f.embed())
             .flat_map(|(f, ty)| {
                 backends.iter().map(move |b| {
-                    let span = f.ty.span();
+                    let span = Span::mixed_site().located_at(f.ty.span());
                     let field_ty = to_field_ty_bound(f.ty_for_deserialize())?;
                     Ok(syn::parse_quote_spanned! {span =>
                         #field_ty: diesel::deserialize::FromSqlRow<diesel::dsl::SqlTypeOf<#ty>, #b>

diesel_derives/src/table.rs

@@ -1,5 +1,5 @@
 use diesel_table_macro_syntax::{ColumnDef, TableDecl};
-use proc_macro2::TokenStream;
+use proc_macro2::{Span, TokenStream};
 use syn::parse_quote;
 use syn::Ident;
 
@@ -76,7 +76,7 @@ pub(crate) fn expand(input: TableDecl) -> TokenStream {
             }
             message += "\t}\n}";
 
-            let span = input.table_name.span();
+            let span = Span::mixed_site().located_at(input.table_name.span());
             return quote::quote_spanned! {span=>
                 compile_error!(#message);
             };
@@ -129,7 +129,7 @@ pub(crate) fn expand(input: TableDecl) -> TokenStream {
     let reexport_column_from_dsl = input.column_defs.iter().map(|c| {
         let column_name = &c.column_name;
         if c.column_name == *table_name {
-            let span = c.column_name.span();
+            let span = Span::mixed_site().located_at(c.column_name.span());
             let message = format!(
                 "Column `{column_name}` cannot be named the same as it's table.\n\
                  You may use `#[sql_name = \"{column_name}\"]` to reference the table's \
@@ -684,7 +684,7 @@ fn generate_op_impl(op: &str, tpe: &syn::Ident) -> TokenStream {
 fn expand_column_def(column_def: &ColumnDef) -> TokenStream {
     // TODO get a better span here as soon as that's
     // possible using stable rust
-    let span = column_def.column_name.span();
+    let span = Span::mixed_site().located_at(column_def.column_name.span());
     let meta = &column_def.meta;
     let column_name = &column_def.column_name;
     let sql_name = &column_def.sql_name;

diesel_derives/src/util.rs

@@ -93,7 +93,8 @@ where
 }
 
 pub fn wrap_in_dummy_mod(item: TokenStream) -> TokenStream {
-    // #[allow(unused_qualifications)] can be removed if https://github.com/rust-lang/rust/issues/130277 gets done
+    // allow(unused_qualifications) is here as it hard to unsure the span is correctly set. Should stay until it is
+    // checked by CI. See https://github.com/rust-lang/rust/issues/130277 for more details.
     quote! {
         #[allow(unused_imports)]
         #[allow(unused_qualifications)]