rework Array built-in indexOf/lastIndexOf to use a shared native helper + magic

src/duk_builtin_array.c

@@ -931,12 +931,13 @@ int duk_builtin_array_prototype_unshift(duk_context *ctx) {
  *  indexOf(), lastIndexOf()
  */
 
-/* idx_step == 1 is indexOf, idx_step == -1 is lastIndexOf */
-static int array_indexof_helper(duk_context *ctx, int idx_step) {
+int duk_builtin_array_prototype_indexof_shared(duk_context *ctx) {
 	/* FIXME: types, ensure loop below works when fixed (i must be able to go negative right now) */
 	int nargs;
 	int i, len;
 	int fromIndex;
+	int idx_step = duk_get_magic(ctx) - 1;  /* 0 -> -1, 2 -> +1 */
+	                                        /* idx_step is +1 for indexOf, -1 for lastIndexOf */
 
 	/* lastIndexOf() needs to be a vararg function because we must distinguish
 	 * between an undefined fromIndex and a "not given" fromIndex; indexOf() is
@@ -1019,14 +1020,6 @@ static int array_indexof_helper(duk_context *ctx, int idx_step) {
 	return 1;
 }
 
-int duk_builtin_array_prototype_index_of(duk_context *ctx) {
-	return array_indexof_helper(ctx, 1 /*idx_step*/);
-}
-
-int duk_builtin_array_prototype_last_index_of(duk_context *ctx) {
-	return array_indexof_helper(ctx, -1 /*idx_step*/);
-}
-
 /*
  *  every(), some(), forEach(), map(), filter()
  */

src/duk_builtin_protos.h

@@ -19,8 +19,7 @@ int duk_builtin_array_prototype_slice(duk_context *ctx);
 int duk_builtin_array_prototype_sort(duk_context *ctx);
 int duk_builtin_array_prototype_splice(duk_context *ctx);
 int duk_builtin_array_prototype_unshift(duk_context *ctx);
-int duk_builtin_array_prototype_index_of(duk_context *ctx);
-int duk_builtin_array_prototype_last_index_of(duk_context *ctx);
+int duk_builtin_array_prototype_indexof_shared(duk_context *ctx);
 int duk_builtin_array_prototype_iter_shared(duk_context *ctx);
 int duk_builtin_array_prototype_reduce_shared(duk_context *ctx);
 

src/genbuiltins.py

@@ -416,8 +416,8 @@ bi_array_prototype = {
 		{ 'name': 'sort',			'native': 'duk_builtin_array_prototype_sort',			'length': 1 },
 		{ 'name': 'splice',			'native': 'duk_builtin_array_prototype_splice',			'length': 2,	'varargs': True },
 		{ 'name': 'unshift',			'native': 'duk_builtin_array_prototype_unshift',		'length': 1,	'varargs': True },
-		{ 'name': 'indexOf',			'native': 'duk_builtin_array_prototype_index_of',		'length': 1,	'varargs': True },
-		{ 'name': 'lastIndexOf',		'native': 'duk_builtin_array_prototype_last_index_of',		'length': 1,	'varargs': True },
+		{ 'name': 'indexOf',			'native': 'duk_builtin_array_prototype_indexof_shared',		'length': 1,	'varargs': True,	'magic': { 'type': 'plain', 'value': 2 } },  # magic = 2 -> idx_step = 2 - 1 = +1
+		{ 'name': 'lastIndexOf',		'native': 'duk_builtin_array_prototype_indexof_shared',		'length': 1,	'varargs': True,	'magic': { 'type': 'plain', 'value': 0 } },  # magic = 0 -> idx_step = 0 - 1 = -1
 		{ 'name': 'every',			'native': 'duk_builtin_array_prototype_iter_shared',		'length': 1,	'nargs': 2,	'magic': { 'type': 'plain', 'value': BI_ARRAY_ITER_EVERY } },
 		{ 'name': 'some',			'native': 'duk_builtin_array_prototype_iter_shared',		'length': 1,	'nargs': 2,	'magic': { 'type': 'plain', 'value': BI_ARRAY_ITER_SOME } },
 		{ 'name': 'forEach',			'native': 'duk_builtin_array_prototype_iter_shared',		'length': 1,	'nargs': 2,	'magic': { 'type': 'plain', 'value': BI_ARRAY_ITER_FOREACH } },