Avoid showing error at record usage site

Since the user can already see the error at the type definition site,
showing errors wherver the type is used will be confusing for them.

Author: seafoamteal

compiler-core/src/type_/expression.rs

@@ -3256,13 +3256,14 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
                 // all correspond to positional fields. If this is not the case, then the
                 // user currently has a mistake in the definition of their custom type.
                 //
-                // For example, when a user starts adding a new labelled field to a custom
-                // type constructor, the field label will be parsed as a custom type name
-                // until they type the colon i.e. as a new positional field.
-                let type_ = positional_fields
-                    .get(index as usize)
-                    .ok_or_else(|| Error::UnlabelledAfterlabelled { location })?
-                    .clone();
+                // However, we do not want to show an error here, because it would be
+                // confusing for the programmer. They can already see the error at the type
+                // definition site.
+                let type_ = if let Some(type_) = positional_fields.get(index as usize) {
+                    type_.clone()
+                } else {
+                    continue;
+                };
 
                 let mut type_vars = im::HashMap::new();
                 let accessor_type = self.instantiate(accessor_type, &mut type_vars);

compiler-core/src/type_/tests/snapshots/gleam_core__type___tests__errors__no_crash_on_record_update_when_constructor_definition_is_invalid.snap

@@ -22,11 +22,3 @@ error: Unlabelled argument after labelled argument
   │                          ^^^^
 
 All unlabelled arguments must come before any labelled arguments.
-
-error: Unlabelled argument after labelled argument
-  ┌─ /src/one/two.gleam:8:13
-  │
-8 │   let two = Wibble(..one, b: 1)
-  │             ^^^^^^^^^^^^^^^^^^^
-
-All unlabelled arguments must come before any labelled arguments.