update uses inside Diesel to sql_function_v2

that should be almost always backwards compatible because the module
was only pub(crate) anyway.
It is not strictly backwards compatible because diesel-rs#3745 (comment)

diesel/src/expression/count.rs

@@ -1,6 +1,6 @@
 use std::marker::PhantomData;
 
-use super::functions::sql_function;
+use super::functions::sql_function_v2;
 use super::{is_aggregate, AsExpression};
 use super::{Expression, ValidGrouping};
 use crate::backend::Backend;
@@ -9,7 +9,7 @@ use crate::result::QueryResult;
 use crate::sql_types::{BigInt, DieselNumericOps, SingleValue, SqlType};
 use crate::{AppearsOnTable, SelectableExpression};
 
-sql_function! {
+sql_function_v2! {
     /// Creates a SQL `COUNT` expression
     ///
     /// As with most bare functions, this is not exported by default. You can import

diesel/src/expression/functions/aggregate_folding.rs

@@ -1,7 +1,7 @@
-use crate::expression::functions::sql_function;
+use crate::expression::functions::sql_function_v2;
 use crate::sql_types::Foldable;
 
-sql_function! {
+sql_function_v2! {
     /// Represents a SQL `SUM` function. This function can only take types which are
     /// Foldable.
     ///
@@ -21,7 +21,7 @@ sql_function! {
     fn sum<ST: Foldable>(expr: ST) -> ST::Sum;
 }
 
-sql_function! {
+sql_function_v2! {
     /// Represents a SQL `AVG` function. This function can only take types which are
     /// Foldable.
     ///

diesel/src/expression/functions/aggregate_ordering.rs

@@ -1,7 +1,7 @@
 use self::private::SqlOrdAggregate;
-use crate::expression::functions::sql_function;
+use crate::expression::functions::sql_function_v2;
 
-sql_function! {
+sql_function_v2! {
     /// Represents a SQL `MAX` function. This function can only take types which are
     /// ordered.
     ///
@@ -20,7 +20,7 @@ sql_function! {
     fn max<ST: SqlOrdAggregate>(expr: ST) -> ST::Ret;
 }
 
-sql_function! {
+sql_function_v2! {
     /// Represents a SQL `MIN` function. This function can only take types which are
     /// ordered.
     ///

diesel/src/expression/functions/date_and_time.rs

@@ -1,6 +1,6 @@
 use crate::backend::Backend;
 use crate::expression::coerce::Coerce;
-use crate::expression::functions::sql_function;
+use crate::expression::functions::sql_function_v2;
 use crate::expression::{AsExpression, Expression, ValidGrouping};
 use crate::query_builder::*;
 use crate::result::QueryResult;
@@ -27,7 +27,7 @@ impl_selectable_expression!(now);
 
 operator_allowed!(now, Add, add);
 operator_allowed!(now, Sub, sub);
-sql_function! {
+sql_function_v2! {
     /// Represents the SQL `DATE` function. The argument should be a Timestamp
     /// expression, and the return value will be an expression of type Date.
     ///

diesel/src/expression/functions/helper_types.rs

@@ -8,16 +8,16 @@ use crate::expression::operators;
 pub type not<Expr> = operators::Not<Grouped<Expr>>;
 
 /// The return type of [`max(expr)`](crate::dsl::max())
-pub type max<Expr> = super::aggregate_ordering::max::HelperType<SqlTypeOf<Expr>, Expr>;
+pub type max<Expr> = super::aggregate_ordering::max<SqlTypeOf<Expr>, Expr>;
 
 /// The return type of [`min(expr)`](crate::dsl::min())
-pub type min<Expr> = super::aggregate_ordering::min::HelperType<SqlTypeOf<Expr>, Expr>;
+pub type min<Expr> = super::aggregate_ordering::min<SqlTypeOf<Expr>, Expr>;
 
 /// The return type of [`sum(expr)`](crate::dsl::sum())
-pub type sum<Expr> = super::aggregate_folding::sum::HelperType<SqlTypeOf<Expr>, Expr>;
+pub type sum<Expr> = super::aggregate_folding::sum<SqlTypeOf<Expr>, Expr>;
 
 /// The return type of [`avg(expr)`](crate::dsl::avg())
-pub type avg<Expr> = super::aggregate_folding::avg::HelperType<SqlTypeOf<Expr>, Expr>;
+pub type avg<Expr> = super::aggregate_folding::avg<SqlTypeOf<Expr>, Expr>;
 
 /// The return type of [`exists(expr)`](crate::dsl::exists())
 pub type exists<Expr> = crate::expression::exists::Exists<Expr>;

diesel/src/expression/functions/mod.rs

@@ -1,7 +1,7 @@
 //! Helper macros to define custom sql functions
 
 #[doc(inline)]
-pub use diesel_derives::sql_function_proc as sql_function;
+pub use diesel_derives::{sql_function_proc as sql_function, sql_function_v2};
 
 #[macro_export]
 #[doc(hidden)]
@@ -73,7 +73,7 @@ macro_rules! no_arg_sql_function_body {
 /// function.
 #[deprecated(
     since = "2.0.0",
-    note = "Use `sql_function!` instead. See `CHANGELOG.md` for migration instructions"
+    note = "Use `sql_function_v2!` instead. See `CHANGELOG.md` for migration instructions"
 )]
 #[cfg(all(feature = "with-deprecated", not(feature = "without-deprecated")))]
 macro_rules! no_arg_sql_function {

diesel/src/expression/mod.rs

@@ -70,7 +70,7 @@ pub(crate) mod dsl {
     pub use crate::pg::expression::dsl::*;
 
     /// The return type of [`count(expr)`](crate::dsl::count())
-    pub type count<Expr> = super::count::count::HelperType<SqlTypeOf<Expr>, Expr>;
+    pub type count<Expr> = super::count::count<SqlTypeOf<Expr>, Expr>;
 
     /// The return type of [`count_star()`](crate::dsl::count_star())
     pub type count_star = super::count::CountStar;
@@ -79,7 +79,7 @@ pub(crate) mod dsl {
     pub type count_distinct<Expr> = super::count::CountDistinct<SqlTypeOf<Expr>, Expr>;
 
     /// The return type of [`date(expr)`](crate::dsl::date())
-    pub type date<Expr> = super::functions::date_and_time::date::HelperType<Expr>;
+    pub type date<Expr> = super::functions::date_and_time::date<Expr>;
 
     #[cfg(feature = "mysql_backend")]
     pub use crate::mysql::query_builder::DuplicatedKeys;

diesel/src/lib.rs

@@ -57,7 +57,7 @@
 //!   They live in [the `dsl` module](dsl).
 //!   Diesel only supports a very small number of these functions.
 //!   You can declare additional functions you want to use
-//!   with [the `sql_function!` macro][`sql_function!`].
+//!   with [the `sql_function_v2!` macro][`sql_function_v2!`].
 //!
 //! [`std::ops`]: //doc.rust-lang.org/stable/std/ops/index.html
 //!
@@ -639,7 +639,7 @@ pub mod prelude {
     };
 
     #[doc(inline)]
-    pub use crate::expression::functions::sql_function;
+    pub use crate::expression::functions::{sql_function, sql_function_v2};
 
     #[doc(inline)]
     pub use crate::expression::SelectableHelper;

diesel/src/pg/connection/mod.rs

@@ -489,7 +489,7 @@ mod tests {
         assert_eq!(2, connection.statement_cache.len());
     }
 
-    sql_function!(fn lower(x: VarChar) -> VarChar);
+    sql_function_v2!(fn lower(x: VarChar) -> VarChar);
 
     #[test]
     fn queries_with_identical_types_and_binds_but_different_sql_are_cached_separately() {

diesel/src/pg/expression/functions.rs

@@ -1,61 +1,61 @@
 //! PostgreSQL specific functions
 
 use super::expression_methods::InetOrCidr;
-use crate::expression::functions::sql_function;
+use crate::expression::functions::sql_function_v2;
 use crate::sql_types::*;
 
-sql_function! {
+sql_function_v2! {
     /// Creates an abbreviated display format as text.
     #[cfg(feature = "postgres_backend")]
     fn abbrev<T: InetOrCidr + SingleValue>(addr: T) -> Text;
 }
-sql_function! {
+sql_function_v2! {
     /// Computes the broadcast address for the address's network.
     #[cfg(feature = "postgres_backend")]
     fn broadcast<T: InetOrCidr + SingleValue>(addr: T) -> Inet;
 }
-sql_function! {
+sql_function_v2! {
     /// Returns the address's family: 4 for IPv4, 6 for IPv6.
     #[cfg(feature = "postgres_backend")]
     fn family<T: InetOrCidr + SingleValue>(addr: T) -> Integer;
 }
-sql_function! {
+sql_function_v2! {
     /// Returns the IP address as text, ignoring the netmask.
     #[cfg(feature = "postgres_backend")]
     fn host<T: InetOrCidr + SingleValue>(addr: T) -> Text;
 }
-sql_function! {
+sql_function_v2! {
     /// Computes the host mask for the address's network.
     #[cfg(feature = "postgres_backend")]
     fn hostmask<T: InetOrCidr + SingleValue>(addr: T) -> Inet;
 }
-sql_function! {
+sql_function_v2! {
     /// Computes the smallest network that includes both of the given networks.
     #[cfg(feature = "postgres_backend")]
     fn inet_merge<T: InetOrCidr + SingleValue, U: InetOrCidr + SingleValue>(a: T, b: U) -> Cidr;
 }
-sql_function! {
+sql_function_v2! {
     /// Tests whether the addresses belong to the same IP family.
     #[cfg(feature = "postgres_backend")]
     fn inet_same_family<T: InetOrCidr + SingleValue, U: InetOrCidr + SingleValue>(a: T, b: U) -> Bool;
 }
-sql_function! {
+sql_function_v2! {
     /// Returns the netmask length in bits.
     #[cfg(feature = "postgres_backend")]
     fn masklen<T: InetOrCidr + SingleValue>(addr: T) -> Integer;
 }
-sql_function! {
+sql_function_v2! {
     /// Computes the network mask for the address's network.
     #[cfg(feature = "postgres_backend")]
     fn netmask<T: InetOrCidr + SingleValue>(addr: T) -> Inet;
 }
-sql_function! {
+sql_function_v2! {
     /// Returns the network part of the address, zeroing out whatever is to the right of the
     /// netmask. (This is equivalent to casting the value to cidr.)
     #[cfg(feature = "postgres_backend")]
     fn network<T: InetOrCidr + SingleValue>(addr: T) -> Cidr;
 }
-sql_function! {
+sql_function_v2! {
     /// Sets the netmask length for an inet or cidr value.
     /// For inet, the address part does not changes. For cidr, address bits to the right of the new
     /// netmask are set to zero.

diesel/src/pg/metadata_lookup.rs

@@ -214,4 +214,4 @@ table! {
 joinable!(pg_type -> pg_namespace(typnamespace));
 allow_tables_to_appear_in_same_query!(pg_type, pg_namespace);
 
-sql_function! { fn pg_my_temp_schema() -> Oid; }
+sql_function_v2! { fn pg_my_temp_schema() -> Oid; }

diesel/src/sqlite/connection/mod.rs

@@ -486,7 +486,7 @@ mod tests {
     }
 
     use crate::sql_types::Text;
-    sql_function!(fn fun_case(x: Text) -> Text);
+    sql_function_v2!(fn fun_case(x: Text) -> Text);
 
     #[test]
     fn register_custom_function() {
@@ -511,7 +511,7 @@ mod tests {
         assert_eq!("fOoBaR", mapped_string);
     }
 
-    sql_function!(fn my_add(x: Integer, y: Integer) -> Integer);
+    sql_function_v2!(fn my_add(x: Integer, y: Integer) -> Integer);
 
     #[test]
     fn register_multiarg_function() {
@@ -522,7 +522,7 @@ mod tests {
         assert_eq!(Ok(3), added);
     }
 
-    sql_function!(fn answer() -> Integer);
+    sql_function_v2!(fn answer() -> Integer);
 
     #[test]
     fn register_noarg_function() {
@@ -542,7 +542,7 @@ mod tests {
         assert_eq!(Ok(42), answer);
     }
 
-    sql_function!(fn add_counter(x: Integer) -> Integer);
+    sql_function_v2!(fn add_counter(x: Integer) -> Integer);
 
     #[test]
     fn register_nondeterministic_function() {
@@ -561,7 +561,7 @@ mod tests {
 
     use crate::sqlite::SqliteAggregateFunction;
 
-    sql_function! {
+    sql_function_v2! {
         #[aggregate]
         fn my_sum(expr: Integer) -> Integer;
     }
@@ -631,7 +631,7 @@ mod tests {
         assert_eq!(Ok(0), result);
     }
 
-    sql_function! {
+    sql_function_v2! {
         #[aggregate]
         fn range_max(expr1: Integer, expr2: Integer, expr3: Integer) -> Nullable<Integer>;
     }

diesel/src/sqlite/mod.rs

@@ -20,9 +20,9 @@ pub use self::query_builder::SqliteQueryBuilder;
 
 /// Trait for the implementation of a SQLite aggregate function
 ///
-/// This trait is to be used in conjunction with the `sql_function!`
+/// This trait is to be used in conjunction with the `sql_function_v2!`
 /// macro for defining a custom SQLite aggregate function. See
-/// the documentation [there](super::prelude::sql_function!) for details.
+/// the documentation [there](super::prelude::sql_function_v2!) for details.
 pub trait SqliteAggregateFunction<Args>: Default {
     /// The result type of the SQLite aggregate function
     type Output;

diesel/src/sqlite/types/date_and_time/chrono.rs

@@ -249,9 +249,9 @@ mod tests {
     use crate::sql_types::{Text, Time, Timestamp, TimestamptzSqlite};
     use crate::test_helpers::connection;
 
-    sql_function!(fn datetime(x: Text) -> Timestamp);
-    sql_function!(fn time(x: Text) -> Time);
-    sql_function!(fn date(x: Text) -> Date);
+    sql_function_v2!(fn datetime(x: Text) -> Timestamp);
+    sql_function_v2!(fn time(x: Text) -> Time);
+    sql_function_v2!(fn date(x: Text) -> Date);
 
     #[test]
     fn unix_epoch_encodes_correctly() {

diesel/src/sqlite/types/date_and_time/time.rs

@@ -275,9 +275,9 @@ mod tests {
     use crate::sql_types::{Text, Time, Timestamp, TimestamptzSqlite};
     use crate::test_helpers::connection;
 
-    sql_function!(fn datetime(x: Text) -> Timestamp);
-    sql_function!(fn time(x: Text) -> Time);
-    sql_function!(fn date(x: Text) -> Date);
+    sql_function_v2!(fn datetime(x: Text) -> Timestamp);
+    sql_function_v2!(fn time(x: Text) -> Time);
+    sql_function_v2!(fn date(x: Text) -> Date);
 
     #[test]
     fn unix_epoch_encodes_correctly() {

diesel_cli/src/infer_schema_internals/information_schema.rs

@@ -32,7 +32,7 @@ impl DefaultSchema for Pg {
 }
 
 #[cfg(feature = "mysql")]
-sql_function!(fn database() -> VarChar);
+sql_function_v2!(fn database() -> VarChar);
 
 #[cfg(feature = "mysql")]
 impl DefaultSchema for Mysql {

diesel_cli/src/infer_schema_internals/mysql.rs

@@ -10,7 +10,7 @@ use super::information_schema::DefaultSchema;
 use super::table_data::TableName;
 use crate::print_schema::ColumnSorting;
 
-diesel::sql_function! {
+diesel::sql_function_v2! {
     #[sql_name = "NULLIF"]
     fn null_if_text(lhs: sql_types::Text, rhs: sql_types::Text) -> sql_types::Nullable<sql_types::Text>
 }

diesel_cli/src/infer_schema_internals/pg.rs

@@ -71,7 +71,7 @@ fn regclass(table: &TableName) -> Regclass<AsExprOf<String, sql_types::Text>> {
     ))
 }
 
-diesel::sql_function!(fn col_description(table: sql_types::Oid, column_number: sql_types::BigInt) -> sql_types::Nullable<sql_types::Text>);
+diesel::sql_function_v2!(fn col_description(table: sql_types::Oid, column_number: sql_types::BigInt) -> sql_types::Nullable<sql_types::Text>);
 
 pub fn get_table_data(
     conn: &mut PgConnection,
@@ -140,7 +140,7 @@ where
     }
 }
 
-sql_function!(fn obj_description(oid: sql_types::Oid, catalog: sql_types::Text) -> Nullable<Text>);
+sql_function_v2!(fn obj_description(oid: sql_types::Oid, catalog: sql_types::Text) -> Nullable<Text>);
 
 pub fn get_table_comment(
     conn: &mut PgConnection,
@@ -167,7 +167,7 @@ mod information_schema {
     }
 }
 
-sql_function! {
+sql_function_v2! {
     #[aggregate]
     fn array_agg(input: diesel::sql_types::Text) -> diesel::sql_types::Array<diesel::sql_types::Text>;
 }

diesel_compile_tests/tests/fail/cannot_mix_aggregate_and_non_aggregate_selects.rs

@@ -11,7 +11,7 @@ table! {
     }
 }
 
-sql_function!(fn f(x: Nullable<Integer>, y: Nullable<Integer>) -> Nullable<Integer>);
+sql_function_v2!(fn f(x: Nullable<Integer>, y: Nullable<Integer>) -> Nullable<Integer>);
 
 fn main() {
     use self::users::dsl::*;

diesel_compile_tests/tests/fail/cannot_mix_aggregate_and_non_aggregate_selects.stderr

@@ -34,9 +34,9 @@ error[E0277]: the trait bound `diesel::expression::is_aggregate::No: MixedAggreg
 note: required for `__Derived<nullable_int_col, max<Nullable<Integer>, nullable_int_col>>` to implement `ValidGrouping<()>`
   --> tests/fail/cannot_mix_aggregate_and_non_aggregate_selects.rs:14:1
    |
-14 | sql_function!(fn f(x: Nullable<Integer>, y: Nullable<Integer>) -> Nullable<Integer>);
+14 | sql_function_v2!(fn f(x: Nullable<Integer>, y: Nullable<Integer>) -> Nullable<Integer>);
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsatisfied trait bound introduced in this `derive` macro
    = note: 1 redundant requirement hidden
    = note: required for `f<nullable_int_col, max<Nullable<Integer>, nullable_int_col>>` to implement `ValidGrouping<()>`
    = note: required for `SelectStatement<FromClause<users::table>>` to implement `SelectDsl<f::f<columns::nullable_int_col, diesel::expression::functions::aggregate_ordering::max::max<diesel::sql_types::Nullable<diesel::sql_types::Integer>, columns::nullable_int_col>>>`
-   = note: this error originates in the macro `sql_function` which comes from the expansion of the derive macro `ValidGrouping` (in Nightly builds, run with -Z macro-backtrace for more info)
+   = note: this error originates in the macro `sql_function_v2` which comes from the expansion of the derive macro `ValidGrouping` (in Nightly builds, run with -Z macro-backtrace for more info)