message: simplify and avoid duplication
diff: @@ -319,8 +319,7 @@ impl<A: AllowedOptions> SalsaStruct<A> {
  let field_getter = field.get_name();
  let field_ty = field.ty();
  - if self.is_identity_field(field) {
  - parse_quote_spanned! {field.field.span() =>
  + let field_debug = quote_spanned! { field.field.span() =>
  debug_struct = debug_struct.field(
  #field_name_string,
  &::salsa::debug::helper::SalsaDebug::<#field_ty, #db_type>::salsa_debug(
  @@ -330,23 +329,19 @@ impl<A: AllowedOptions> SalsaStruct<A> {
  _include_all_fields
  )
  );
  + };
  +
  + if self.is_identity_field(field) {
  + quote_spanned! { field.field.span() =>
  + #field_debug
  }
  } else {
  - parse_quote_spanned! {field.field.span() =>
  + quote_spanned! { field.field.span() =>
  if _include_all_fields {
  - debug_struct = debug_struct.field(
  - #field_name_string,
  - &::salsa::debug::helper::SalsaDebug::<#field_ty, #db_type>::salsa_debug(
  - #[allow(clippy::needless_borrow)]
  - &self.#field_getter(_db),
  - _db,
  - true
  - )
  - );
  + #field_debug
  }
  }
  }
  -
  })
  .collect::<TokenStream>();
  