added jsonb_insert

diesel/src/pg/expression/functions.rs

@@ -1,6 +1,7 @@
 //! PostgreSQL specific functions
 
 use super::expression_methods::InetOrCidr;
+use super::expression_methods::JsonbOrNullableJsonb;
 use crate::expression::functions::define_sql_function;
 use crate::pg::expression::expression_methods::ArrayOrNullableArray;
 use crate::pg::expression::expression_methods::MaybeNullableValue;
@@ -1634,3 +1635,48 @@ define_sql_function! {
         text_array: Arr,
     ) -> Arr::Out;
 }
+
+#[cfg(feature = "postgres_backend")]
+define_sql_function! {
+    /// Returns target with new_value inserted. If the item designated by the path is an array element
+    ///
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// # include!("../../doctest_setup.rs");
+    /// #
+    /// # fn main() {
+    /// #     run_test().unwrap();
+    /// # }
+    /// #
+    /// # fn run_test() -> QueryResult<()> {
+    /// #     use diesel::dsl::jsonb_insert;
+    /// #     use diesel::sql_types::{Array, Jsonb, Nullable, Text};
+    /// #     use serde_json::{Value, json};
+    /// #     let connection = &mut establish_connection();
+    /// let result = diesel::select(jsonb_insert::<Jsonb, Array<Text>, _, _, _>(json!([1, 2, 3]), vec!["1"], json!(1)))
+    ///                 .get_result::<Value>(connection)?;
+    /// assert_eq!(json!([1, 1, 2, 3]), result);
+    ///
+    /// let result = diesel::select(jsonb_insert::<Jsonb, Array<Text>, _, _, _>(json!([1, 2, 3]), Vec::<String>::new(), json!(1)))
+    ///                 .get_result::<Value>(connection)?;
+    /// assert_eq!(json!([1, 2, 3]), result);
+    ///
+    /// let result = diesel::select(jsonb_insert::<Nullable<Jsonb>, Array<Text>, _, _, _>(Option::<Value>::None, vec!["1"], json!(1)))
+    ///                 .get_result::<Option<Value>>(connection)?;
+    /// assert_eq!(None, result);
+    ///
+    /// let result = diesel::select(jsonb_insert::<Nullable<Jsonb>, Array<Text>, _, _, _>(json!([1, 2, 3]), vec!["1"], Option::<Value>::None))
+    ///                 .get_result::<Option<Value>>(connection)?;
+    /// assert_eq!(None, result);
+    ///
+    /// let result = diesel::select(jsonb_insert::<Jsonb, Nullable<Array<Text>>, _, _, _>(json!([1, 2, 3]), None::<Vec<String>>, json!(1)))
+    ///                 .get_result::<Value>(connection)?;
+    /// assert!(result.is_err());
+    ///
+    /// #     Ok(())
+    /// # }
+    /// ```
+    fn jsonb_insert<J: JsonbOrNullableJsonb + MaybeNullableValue<Jsonb>, P: TextArrayOrNullableTextArray + MaybeNullableValue<Jsonb>>(target: J, path: P, value: J) -> J::Out;
+}

diesel/src/pg/expression/helper_types.rs

@@ -486,3 +486,9 @@ pub type to_jsonb<E> = super::functions::to_jsonb<SqlTypeOf<E>, E>;
 #[allow(non_camel_case_types)]
 #[cfg(feature = "postgres_backend")]
 pub type json_object<A> = super::functions::json_object<SqlTypeOf<A>, A>;
+
+/// Return type of [`jsonb_insert(target, path, value)`](super::functions::json_object())
+#[allow(non_camel_case_types)]
+#[cfg(feature = "postgres_backend")]
+pub type jsonb_insert<T, P, V> =
+    super::functions::jsonb_insert<SqlTypeOf<T>, SqlTypeOf<P>, T, P, V>;

diesel_derives/tests/auto_type.rs

@@ -438,6 +438,7 @@ fn postgres_functions() -> _ {
         to_json(pg_extras::id),
         to_jsonb(pg_extras::id),
         json_object(pg_extras::text_array),
+        jsonb_insert(pg_extras::jsonb, pg_extras::text_array, pg_extras::jsonb),
     )
 }