Add support for readonly

See #7 (comment)

Author: thekid

ChangeLog.md

@@ -3,6 +3,10 @@ XP records for PHP - ChangeLog
 
 ## ?.?.? / ????-??-??
 
+## 2.3.0 / 2022-02-05
+
+* Add support for `readonly` record parameters. See issue #7 - @thekid
+
 ## 2.2.0 / 2022-02-03
 
 * Merged PR #8: Replace `__init()` function with `init { }` blocks

src/test/php/lang/ast/syntax/php/unittest/RecordsTest.class.php

@@ -34,6 +34,30 @@ public function __construct() { }
     }');
   }
 
+  #[Test]
+  public function fields_are_private_by_default() {
+    $t= $this->type('record <T>(string $name) { }');
+    Assert::equals(MODIFIER_PRIVATE, $t->getField('name')->getModifiers());
+  }
+
+  #[Test]
+  public function can_declare_field_modifiers() {
+    $t= $this->type('record <T>(public string $name) { }');
+    Assert::equals(MODIFIER_PUBLIC, $t->getField('name')->getModifiers());
+  }
+
+  #[Test]
+  public function can_have_readonly_fields() {
+    $t= $this->type('record <T>(public readonly string $name) { }');
+    Assert::equals(MODIFIER_PUBLIC | MODIFIER_READONLY, $t->getField('name')->getModifiers());
+  }
+
+  #[Test, Expect(class: Error::class, withMessage: '/Cannot modify readonly property .+name/')]
+  public function writing_to_readonly_field() {
+    $t= $this->type('record <T>(public readonly string $name) { }');
+    $t->newInstance('Test')->name= 'Modified';
+  }
+
   #[Test]
   public function point_record() {
     $p= $this->type('record <T>(int $x, int $y) { }')->newInstance(1, 10);