GH-15976: clarify error messages for enum/trait/interface/alias names

Instead of always saying that a name is reserved or deprecated and
cannot/should not be used as a class name, take the usage into account and say
the name cannot be used as an enum name, trait name, etc. In the process, for
class names add a missing "a".

Author: DanielEScherzer

Zend/tests/gh15976/alias-names.phpt

@@ -8,6 +8,6 @@ class_alias( 'stdClass', 'bool' );
 
 ?>
 --EXPECTF--
-Deprecated: Using "_" as a class name is deprecated since 8.4 in %salias-names.php on line 3
+Deprecated: Using "_" as a type alias is deprecated since 8.4 in %salias-names.php on line 3
 
-Fatal error: Cannot use 'bool' as class name as it is reserved in %salias-names.php on line 4
+Fatal error: Cannot use 'bool' as a type alias as it is reserved in %salias-names.php on line 4

Zend/tests/gh15976/class-names.phpt

@@ -10,4 +10,4 @@ class bool {}
 --EXPECTF--
 Deprecated: Using "_" as a class name is deprecated since 8.4 in %sclass-names.php on line 3
 
-Fatal error: Cannot use 'bool' as class name as it is reserved in %sclass-names.php on line 4
+Fatal error: Cannot use 'bool' as a class name as it is reserved in %sclass-names.php on line 4

Zend/tests/gh15976/enum-names.phpt

@@ -8,6 +8,6 @@ enum bool {}
 
 ?>
 --EXPECTF--
-Deprecated: Using "_" as a class name is deprecated since 8.4 in %senum-names.php on line 3
+Deprecated: Using "_" as an enum name is deprecated since 8.4 in %senum-names.php on line 3
 
-Fatal error: Cannot use 'bool' as class name as it is reserved in %senum-names.php on line 4
+Fatal error: Cannot use 'bool' as an enum name as it is reserved in %senum-names.php on line 4

Zend/tests/gh15976/interface-names.phpt

@@ -8,6 +8,6 @@ interface bool {}
 
 ?>
 --EXPECTF--
-Deprecated: Using "_" as a class name is deprecated since 8.4 in %sinterface-names.php on line 3
+Deprecated: Using "_" as an interface name is deprecated since 8.4 in %sinterface-names.php on line 3
 
-Fatal error: Cannot use 'bool' as class name as it is reserved in %sinterface-names.php on line 4
+Fatal error: Cannot use 'bool' as an interface name as it is reserved in %sinterface-names.php on line 4

Zend/tests/gh15976/trait-names.phpt

@@ -8,6 +8,6 @@ trait bool {}
 
 ?>
 --EXPECTF--
-Deprecated: Using "_" as a class name is deprecated since 8.4 in %strait-names.php on line 3
+Deprecated: Using "_" as a trait name is deprecated since 8.4 in %strait-names.php on line 3
 
-Fatal error: Cannot use 'bool' as class name as it is reserved in %strait-names.php on line 4
+Fatal error: Cannot use 'bool' as a trait name as it is reserved in %strait-names.php on line 4

Zend/zend_API.c

@@ -3571,7 +3571,7 @@ ZEND_API zend_result zend_register_class_alias_ex(const char *name, size_t name_
 		zend_str_tolower_copy(ZSTR_VAL(lcname), name, name_len);
 	}
 
-	zend_assert_valid_class_name(lcname);
+	zend_assert_valid_class_name(lcname, "a type alias");
 
 	lcname = zend_new_interned_string(lcname);
 

Zend/zend_compile.c

@@ -237,14 +237,14 @@ static bool zend_is_reserved_class_name(const zend_string *name) /* {{{ */
 }
 /* }}} */
 
-void zend_assert_valid_class_name(const zend_string *name) /* {{{ */
+void zend_assert_valid_class_name(const zend_string *name, const char *type) /* {{{ */
 {
 	if (zend_is_reserved_class_name(name)) {
 		zend_error_noreturn(E_COMPILE_ERROR,
-			"Cannot use '%s' as class name as it is reserved", ZSTR_VAL(name));
+			"Cannot use '%s' as %s as it is reserved", ZSTR_VAL(name), type);
 	}
 	if (zend_string_equals_literal(name, "_")) {
-		zend_error(E_DEPRECATED, "Using \"_\" as a class name is deprecated since 8.4");
+		zend_error(E_DEPRECATED, "Using \"_\" as %s is deprecated since 8.4", type);
 	}
 }
 /* }}} */
@@ -6985,7 +6985,7 @@ static zend_type zend_compile_single_typename(zend_ast *ast)
 			uint32_t fetch_type = zend_get_class_fetch_type_ast(ast);
 			if (fetch_type == ZEND_FETCH_CLASS_DEFAULT) {
 				class_name = zend_resolve_class_name_ast(ast);
-				zend_assert_valid_class_name(class_name);
+				zend_assert_valid_class_name(class_name, "a class name");
 			} else {
 				zend_ensure_valid_class_fetch_type(fetch_type);
 				zend_string_addref(class_name);
@@ -8996,7 +8996,15 @@ static void zend_compile_class_decl(znode *result, zend_ast *ast, bool toplevel)
 			zend_error_noreturn(E_COMPILE_ERROR, "Class declarations may not be nested");
 		}
 
-		zend_assert_valid_class_name(unqualified_name);
+		const char *type = "a class name";
+		if (decl->flags & ZEND_ACC_ENUM) {
+			type = "an enum name";
+		} else if (decl->flags & ZEND_ACC_INTERFACE) {
+			type = "an interface name";
+		} else if (decl->flags & ZEND_ACC_TRAIT) {
+			type = "a trait name";
+		}
+		zend_assert_valid_class_name(unqualified_name, type);
 		name = zend_prefix_with_ns(unqualified_name);
 		name = zend_new_interned_string(name);
 		lcname = zend_string_tolower(name);

Zend/zend_compile.h

@@ -1001,7 +1001,7 @@ ZEND_API void zend_set_function_arg_flags(zend_function *func);
 
 int ZEND_FASTCALL zendlex(zend_parser_stack_elem *elem);
 
-void zend_assert_valid_class_name(const zend_string *const_name);
+void zend_assert_valid_class_name(const zend_string *const_name, const char *type);
 
 zend_string *zend_type_to_string_resolved(zend_type type, zend_class_entry *scope);
 ZEND_API zend_string *zend_type_to_string(zend_type type);