Covariance on inheriting classes with iterable

trowski · trowski · commit 4da3e77b4ce4 · 2016-06-04T09:44:49.000-05:00
diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
@@ -1253,17 +1253,20 @@ static void zend_mark_function_as_generator() /* {{{ */
 	}
 
 	if (CG(active_op_array)->fn_flags & ZEND_ACC_HAS_RETURN_TYPE) {
-		const char *msg = "Generators may only declare a return type of Generator, Iterator or Traversable, %s is not permitted";
 		zend_arg_info return_info = CG(active_op_array)->arg_info[-1];
 
-		if (!return_info.class_name) {
-			zend_error_noreturn(E_COMPILE_ERROR, msg, zend_get_type_by_const(return_info.type_hint));
-		}
+		if (return_info.type_hint != IS_ITERABLE) {
+			const char *msg = "Generators may only declare a return type of Generator, Iterator, Traversable, or iterable, %s is not permitted";
+			
+			if (!return_info.class_name) {
+				zend_error_noreturn(E_COMPILE_ERROR, msg, zend_get_type_by_const(return_info.type_hint));
+			}
 
-		if (!zend_string_equals_literal_ci(return_info.class_name, "Traversable")
-			&& !zend_string_equals_literal_ci(return_info.class_name, "Iterator")
-			&& !zend_string_equals_literal_ci(return_info.class_name, "Generator")) {
-			zend_error_noreturn(E_COMPILE_ERROR, msg, ZSTR_VAL(return_info.class_name));
+			if (!zend_string_equals_literal_ci(return_info.class_name, "Traversable")
+				&& !zend_string_equals_literal_ci(return_info.class_name, "Iterator")
+				&& !zend_string_equals_literal_ci(return_info.class_name, "Generator")) {
+				zend_error_noreturn(E_COMPILE_ERROR, msg, ZSTR_VAL(return_info.class_name));
+			}
 		}
 	}
 
diff --git a/Zend/zend_inheritance.c b/Zend/zend_inheritance.c
@@ -22,6 +22,7 @@
 #include "zend_compile.h"
 #include "zend_execute.h"
 #include "zend_inheritance.h"
+#include "zend_interfaces.h"
 #include "zend_smart_str.h"
 #include "zend_inheritance.h"
 
@@ -167,6 +168,26 @@ char *zend_visibility_string(uint32_t fn_flags) /* {{{ */
 }
 /* }}} */
 
+static zend_bool zend_iterable_type_check(zend_arg_info *arg_info) /* {{{ */
+{
+	if (arg_info->class_name) {
+		zend_class_entry *ce;
+		
+		ce = zend_lookup_class(arg_info->class_name);
+		
+		if (ce && instanceof_function(ce, zend_ce_traversable)) {
+			return 1;
+		}
+	}
+	
+	if (arg_info->type_hint == IS_ITERABLE || arg_info->type_hint == IS_ARRAY) {
+		return 1;
+	}
+	
+	return 0;
+}
+/* }}} */
+
 static int zend_do_perform_type_hint_check(const zend_function *fe, zend_arg_info *fe_arg_info, const zend_function *proto, zend_arg_info *proto_arg_info) /* {{{ */
 {
 	if (ZEND_LOG_XOR(fe_arg_info->class_name, proto_arg_info->class_name)) {
@@ -314,6 +335,10 @@ static zend_bool zend_do_perform_implementation_check(const zend_function *fe, c
 		} else {
 			proto_arg_info = &proto->common.arg_info[proto->common.num_args];
 		}
+		
+		if (fe_arg_info->type_hint == IS_ITERABLE && zend_iterable_type_check(proto_arg_info)) {
+			continue;
+		}
 
 		if (!zend_do_perform_type_hint_check(fe, fe_arg_info, proto, proto_arg_info)) {
 			return 0;
@@ -338,6 +363,10 @@ static zend_bool zend_do_perform_implementation_check(const zend_function *fe, c
 		if (!(fe->common.fn_flags & ZEND_ACC_HAS_RETURN_TYPE)) {
 			return 0;
 		}
+		
+		if (proto->common.arg_info[-1].type_hint == IS_ITERABLE && zend_iterable_type_check(fe->common.arg_info - 1)) {
+			return 1;
+		}
 
 		if (!zend_do_perform_type_hint_check(fe, fe->common.arg_info - 1, proto, proto->common.arg_info - 1)) {
 			return 0;
