feat: record type spread

Author: zweimach

grammar.js

@@ -105,7 +105,8 @@ module.exports = grammar({
     [$._reserved_identifier, $.function],
     [$.exception_pattern, $.or_pattern],
     [$.type_binding, $._inline_type],
-    [$._module_structure, $.parenthesized_module_expression]
+    [$._module_structure, $.parenthesized_module_expression],
+    [$.record_type_field, $.object_type_field],
   ],
 
   rules: {
@@ -382,11 +383,14 @@ module.exports = grammar({
       '}',
     ),
 
-    record_type_field: $ => seq(
-      optional('mutable'),
-      alias($.value_identifier, $.property_identifier),
-      optional('?'),
-      $.type_annotation,
+    record_type_field: $ => choice(
+      seq('...', choice($.type_identifier, $.type_identifier_path)),
+      seq(
+        optional('mutable'),
+        alias($.value_identifier, $.property_identifier),
+        optional('?'),
+        $.type_annotation,
+      ),
     ),
 
     object_type: $ => prec.left(seq(

test/corpus/type_declarations.txt

@@ -106,6 +106,12 @@ type t = Mod.t = {a: int}
 
 type t = {}
 
+type t = {
+  ...a,
+  ...b,
+  other: int,
+}
+
 --------------------------------------------------------------------------------
 
 (source_file
@@ -147,7 +153,19 @@ type t = {}
   (type_declaration
     (type_binding
       (type_identifier)
-      (record_type))))
+      (record_type)))
+  (type_declaration
+    (type_binding
+      (type_identifier)
+      (record_type
+        (record_type_field
+          (type_identifier))
+        (record_type_field
+          (type_identifier))
+        (record_type_field
+          (property_identifier)
+          (type_annotation
+            (type_identifier)))))))
 
 ================================================================================
 Extensible Variant