Add RbDefineConst

README.md

@@ -201,7 +201,7 @@ ref. https://docs.ruby-lang.org/ja/latest/function/index.html
 * [ ] `rb_define_class_id`
 * [x] `rb_define_class_under`
 * [ ] `rb_define_class_variable`
-* [ ] `rb_define_const`
+* [x] `rb_define_const`
 * [ ] `rb_define_global_const`
 * [ ] `rb_define_global_function`
 * [ ] `rb_define_hooked_variable`

ruby-internal-variable.go

@@ -18,3 +18,15 @@ func RbDefineVariable(name string, v *VALUE) {
 
 	C.rb_define_variable(char, (*C.VALUE)(v))
 }
+
+// RbDefineConst calls `rb_define_const` in C
+//
+// Original definition is following
+//
+//	void rb_define_const(VALUE klass, const char *name, VALUE val)
+func RbDefineConst(klass VALUE, name string, val VALUE) {
+	char, clean := string2Char(name)
+	defer clean()
+
+	C.rb_define_const(C.VALUE(klass), char, C.VALUE(val))
+}

testdata/dummy/ext/dummy/tests.go

@@ -30,6 +30,7 @@ VALUE rb_dummy_tests_rb_ary_pop(VALUE self, VALUE ary);
 VALUE rb_dummy_tests_rb_ary_shift(VALUE self, VALUE ary);
 VALUE rb_dummy_tests_rb_ary_unshift(VALUE self, VALUE ary, VALUE elem);
 void  rb_dummy_tests_rb_define_variable(VALUE self, VALUE name, VALUE v);
+void  rb_dummy_tests_rb_define_const(VALUE self, VALUE name, VALUE val);
 */
 import "C"
 
@@ -262,6 +263,12 @@ func rb_dummy_tests_rb_define_variable(_ C.VALUE, name C.VALUE, v C.VALUE) {
 	ruby.RbDefineVariable(strName, (*ruby.VALUE)(&v))
 }
 
+//export rb_dummy_tests_rb_define_const
+func rb_dummy_tests_rb_define_const(self C.VALUE, name C.VALUE, val C.VALUE) {
+	strName := ruby.Value2String(ruby.VALUE(name))
+	ruby.RbDefineConst(ruby.VALUE(self), strName, ruby.VALUE(val))
+}
+
 // defineMethodsToDummyTests define methods in Dummy::Tests
 func defineMethodsToDummyTests(rb_mDummy ruby.VALUE) {
 	rb_cTests := ruby.RbDefineClassUnder(rb_mDummy, "Tests", ruby.VALUE(C.rb_cObject))
@@ -295,4 +302,5 @@ func defineMethodsToDummyTests(rb_mDummy ruby.VALUE) {
 	ruby.RbDefineSingletonMethod(rb_cTests, "rb_ary_shift", C.rb_dummy_tests_rb_ary_shift, 1)
 	ruby.RbDefineSingletonMethod(rb_cTests, "rb_ary_unshift", C.rb_dummy_tests_rb_ary_unshift, 2)
 	ruby.RbDefineSingletonMethod(rb_cTests, "rb_define_variable", C.rb_dummy_tests_rb_define_variable, 2)
+	ruby.RbDefineSingletonMethod(rb_cTests, "rb_define_const", C.rb_dummy_tests_rb_define_const, 2)
 }

testdata/dummy/sig/dummy/tests.rbs

@@ -37,6 +37,7 @@ module Dummy
     def self.rb_ary_shift: ([] ary) -> untyped
     def self.rb_ary_unshift: ([] ary, untyped elem) -> []
     def self.rb_define_variable: (string name, untyped var) -> void
+    def self.rb_define_const: (string name, untyped val) -> void
 
     private
     def nop_rb_define_private_method: () -> void

testdata/dummy/test/dummy/tests_test.rb

@@ -179,5 +179,14 @@ class RbAttrTest < Test::Unit::TestCase
       $global_var = nil
     end
     # rubocop:enable Style/GlobalVars
+
+    test ".rb_define_const" do
+      Dummy::Tests.rb_define_const("RB_DEFINE_CONST", 1)
+      assert { Dummy::Tests::RB_DEFINE_CONST == 1 }
+    ensure
+      Dummy::Tests.class_eval do
+        remove_const(:RB_DEFINE_CONST) if const_defined?(:RB_DEFINE_CONST, false)
+      end
+    end
   end
 end