Added custom array example with documentation.

Cargo.toml

@@ -21,6 +21,7 @@ members = [
     "examples/postgres/getting_started_step_1",
     "examples/postgres/getting_started_step_2",
     "examples/postgres/getting_started_step_3",
+    "examples/postgres/custom_arrays",
     "examples/postgres/custom_types",
     "examples/postgres/composite_types",
     "examples/postgres/relations",

diesel_tests/tests/joins.rs

@@ -438,12 +438,14 @@ fn join_with_explicit_on_clause() {
 
     let data = users::table
         .inner_join(posts::table.on(posts::title.eq("Post One")))
+        .order(users::id)
         .load(connection);
 
     assert_eq!(expected_data, data);
 
     let data = users::table
         .inner_join(posts::table.on(posts::title.eq_any(vec!["Post One"])))
+        .order(users::id)
         .load(connection);
 
     assert_eq!(expected_data, data);

examples/postgres/custom_arrays/.gitignore

@@ -0,0 +1,2 @@
+/target
+/.env

examples/postgres/custom_arrays/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "custom_arrays"
+version = "0.1.0"
+edition.workspace = true
+publish = false
+
+[dependencies]
+diesel = { path = "../../../diesel", version = "2.2.0", default-features = false, features = ["postgres", "r2d2"] }
+diesel_migrations = { path = "../../../diesel_migrations", version = "2.2.0", default-features = false, features = ["postgres"] }
+
+[dev-dependencies]
+dotenvy = "0.15"