Improve error message class type

Refer to interfaces/enums instead of classes in more places.

Closes GH-7792
Closes GH-8187

NEWS

@@ -8,6 +8,7 @@ PHP                                                                        NEWS
 - Core:
   . Fixed bug #81380 (Observer may not be initialized properly). (krakjoe)
   . Fixed bug GH-7771 (Fix filename/lineno of constant expressions). (ilutov)
+  . Fixed bug GH-7792 (Improve class type in error messages). (ilutov)
 
 - Intl:
   . Update all grandfathered language tags with preferred values

Zend/tests/class_alias_009.phpt

@@ -11,4 +11,4 @@ interface c extends a, b { }
 
 ?>
 --EXPECTF--
-Fatal error: Class c cannot implement previously implemented interface a in %s on line %d
+Fatal error: Interface c cannot implement previously implemented interface a in %s on line %d

Zend/tests/constants/final_constants/final_const12.phpt

@@ -19,4 +19,4 @@ interface I3 extends I1, I2
 
 ?>
 --EXPECTF--
-Fatal error: Class I3 inherits both I1::C and I2::C, which is ambiguous in %s on line %d
+Fatal error: Interface I3 inherits both I1::C and I2::C, which is ambiguous in %s on line %d

Zend/tests/enum/no-enum-implements-backed-enum.phpt

@@ -7,4 +7,4 @@ enum Foo: int implements BackedEnum {}
 
 ?>
 --EXPECTF--
-Fatal error: Class Foo cannot implement previously implemented interface BackedEnum in %s on line %d
+Fatal error: Enum Foo cannot implement previously implemented interface BackedEnum in %s on line %d

Zend/tests/enum/no-enum-implements-unit-enum.phpt

@@ -7,4 +7,4 @@ enum Foo implements UnitEnum {}
 
 ?>
 --EXPECTF--
-Fatal error: Class Foo cannot implement previously implemented interface UnitEnum in %s on line %d
+Fatal error: Enum Foo cannot implement previously implemented interface UnitEnum in %s on line %d

Zend/tests/gh7792_1.phpt

@@ -0,0 +1,14 @@
+--TEST--
+GH-7792 (Refer to enum as enum instead of class)
+--FILE--
+<?php
+
+interface A {
+    public function a(): void;
+}
+
+enum B implements A {}
+
+?>
+--EXPECTF--
+Fatal error: Enum B must implement 1 abstract private method (A::a) in %s on line %d

Zend/tests/gh7792_2.phpt

@@ -0,0 +1,10 @@
+--TEST--
+GH-7792 (Refer to enum as enum instead of class)
+--FILE--
+<?php
+
+enum Foo implements Throwable {}
+
+?>
+--EXPECTF--
+Fatal error: Enum Foo cannot implement interface Throwable in %s on line %d

Zend/tests/gh7792_3.phpt

@@ -0,0 +1,18 @@
+--TEST--
+GH-7792 (Refer to enum as enum instead of class)
+--FILE--
+<?php
+
+interface A {
+    const FOO = 'foo';
+}
+
+interface B {
+    const FOO = 'foo';
+}
+
+enum Foo implements A, B {}
+
+?>
+--EXPECTF--
+Fatal error: Enum Foo inherits both A::FOO and B::FOO, which is ambiguous in %s on line %d

Zend/tests/gh7792_4.phpt

@@ -0,0 +1,12 @@
+--TEST--
+GH-7792 (Refer to enum as enum instead of class)
+--FILE--
+<?php
+
+interface A {}
+
+enum Foo implements A, A {}
+
+?>
+--EXPECTF--
+Fatal error: Enum Foo cannot implement previously implemented interface A in %s on line %d

Zend/tests/gh7792_5.phpt

@@ -0,0 +1,10 @@
+--TEST--
+GH-7792 (Refer to enum as enum instead of class)
+--FILE--
+<?php
+
+enum Foo implements Traversable {}
+
+?>
+--EXPECT--
+Fatal error: Enum Foo must implement interface Traversable as part of either Iterator or IteratorAggregate in Unknown on line 0

Zend/tests/objects_014.phpt

@@ -12,4 +12,4 @@ interface bar extends foo, foo {
 echo "Done\n";
 ?>
 --EXPECTF--
-Fatal error: Class bar cannot implement previously implemented interface foo in %s on line %d
+Fatal error: Interface bar cannot implement previously implemented interface foo in %s on line %d

Zend/zend_API.c

@@ -4783,14 +4783,16 @@ ZEND_API void zend_restore_error_handling(zend_error_handling *saved) /* {{{ */
 }
 /* }}} */
 
-ZEND_API ZEND_COLD const char *zend_get_object_type(const zend_class_entry *ce) /* {{{ */
+ZEND_API ZEND_COLD const char *zend_get_object_type_case(const zend_class_entry *ce, bool upper_case) /* {{{ */
 {
-	if(ce->ce_flags & ZEND_ACC_TRAIT) {
-		return "trait";
+	if (ce->ce_flags & ZEND_ACC_TRAIT) {
+		return upper_case ? "Trait" : "trait";
 	} else if (ce->ce_flags & ZEND_ACC_INTERFACE) {
-		return "interface";
+		return upper_case ? "Interface" : "interface";
+	} else if (ce->ce_flags & ZEND_ACC_ENUM) {
+		return upper_case ? "Enum" : "enum";
 	} else {
-		return "class";
+		return upper_case ? "Class" : "class";
 	}
 }
 /* }}} */

Zend/zend_API.h

@@ -721,7 +721,17 @@ static zend_always_inline zend_result zend_forbid_dynamic_call(void)
 	return SUCCESS;
 }
 
-ZEND_API ZEND_COLD const char *zend_get_object_type(const zend_class_entry *ce);
+ZEND_API ZEND_COLD const char *zend_get_object_type_case(const zend_class_entry *ce, bool upper_case);
+
+static zend_always_inline const char *zend_get_object_type(const zend_class_entry *ce)
+{
+	return zend_get_object_type_case(ce, false);
+}
+
+static zend_always_inline const char *zend_get_object_type_uc(const zend_class_entry *ce)
+{
+	return zend_get_object_type_case(ce, true);
+}
 
 ZEND_API bool zend_is_iterable(zval *iterable);
 

Zend/zend_exceptions.c

@@ -67,8 +67,13 @@ static int zend_implement_throwable(zend_class_entry *interface, zend_class_entr
 		return SUCCESS;
 	}
 
+	bool can_extend = (class_type->ce_flags & ZEND_ACC_ENUM) == 0;
+
 	zend_error_noreturn(E_ERROR,
-		"Class %s cannot implement interface %s, extend Exception or Error instead",
+		can_extend
+			? "%s %s cannot implement interface %s, extend Exception or Error instead"
+			: "%s %s cannot implement interface %s",
+		zend_get_object_type_uc(class_type),
 		ZSTR_VAL(class_type->name),
 		ZSTR_VAL(interface->name));
 	return FAILURE;

Zend/zend_inheritance.c

@@ -1285,7 +1285,7 @@ static void do_inherit_property(zend_property_info *parent_info, zend_string *ke
 static inline void do_implement_interface(zend_class_entry *ce, zend_class_entry *iface) /* {{{ */
 {
 	if (!(ce->ce_flags & ZEND_ACC_INTERFACE) && iface->interface_gets_implemented && iface->interface_gets_implemented(iface, ce) == FAILURE) {
-		zend_error_noreturn(E_CORE_ERROR, "Class %s could not implement interface %s", ZSTR_VAL(ce->name), ZSTR_VAL(iface->name));
+		zend_error_noreturn(E_CORE_ERROR, "%s %s could not implement interface %s", zend_get_object_type_uc(ce), ZSTR_VAL(ce->name), ZSTR_VAL(iface->name));
 	}
 	/* This should be prevented by the class lookup logic. */
 	ZEND_ASSERT(ce != iface);
@@ -1610,7 +1610,8 @@ static bool do_inherit_constant_check(
 
 	if (old_constant->ce != parent_constant->ce && old_constant->ce != ce) {
 		zend_error_noreturn(E_COMPILE_ERROR,
-			"Class %s inherits both %s::%s and %s::%s, which is ambiguous",
+			"%s %s inherits both %s::%s and %s::%s, which is ambiguous",
+			zend_get_object_type_uc(ce),
 			ZSTR_VAL(ce->name),
 			ZSTR_VAL(old_constant->ce->name), ZSTR_VAL(name),
 			ZSTR_VAL(parent_constant->ce->name), ZSTR_VAL(name));
@@ -1729,7 +1730,10 @@ static void zend_do_implement_interfaces(zend_class_entry *ce, zend_class_entry
 			if (interfaces[j] == iface) {
 				if (j >= num_parent_interfaces) {
 					efree(interfaces);
-					zend_error_noreturn(E_COMPILE_ERROR, "Class %s cannot implement previously implemented interface %s", ZSTR_VAL(ce->name), ZSTR_VAL(iface->name));
+					zend_error_noreturn(E_COMPILE_ERROR, "%s %s cannot implement previously implemented interface %s",
+						zend_get_object_type_uc(ce),
+						ZSTR_VAL(ce->name),
+						ZSTR_VAL(iface->name));
 					return;
 				}
 				/* skip duplications */
@@ -2311,6 +2315,7 @@ void zend_verify_abstract_class(zend_class_entry *ce) /* {{{ */
 	zend_function *func;
 	zend_abstract_info ai;
 	bool is_explicit_abstract = (ce->ce_flags & ZEND_ACC_EXPLICIT_ABSTRACT_CLASS) != 0;
+	bool can_be_abstract = (ce->ce_flags & ZEND_ACC_ENUM) == 0;
 	memset(&ai, 0, sizeof(ai));
 
 	ZEND_HASH_MAP_FOREACH_PTR(&ce->function_table, func) {
@@ -2324,9 +2329,10 @@ void zend_verify_abstract_class(zend_class_entry *ce) /* {{{ */
 	} ZEND_HASH_FOREACH_END();
 
 	if (ai.cnt) {
-		zend_error_noreturn(E_ERROR, !is_explicit_abstract
-			? "Class %s contains %d abstract method%s and must therefore be declared abstract or implement the remaining methods (" MAX_ABSTRACT_INFO_FMT MAX_ABSTRACT_INFO_FMT MAX_ABSTRACT_INFO_FMT ")"
-			: "Class %s must implement %d abstract private method%s (" MAX_ABSTRACT_INFO_FMT MAX_ABSTRACT_INFO_FMT MAX_ABSTRACT_INFO_FMT ")",
+		zend_error_noreturn(E_ERROR, !is_explicit_abstract && can_be_abstract
+			? "%s %s contains %d abstract method%s and must therefore be declared abstract or implement the remaining methods (" MAX_ABSTRACT_INFO_FMT MAX_ABSTRACT_INFO_FMT MAX_ABSTRACT_INFO_FMT ")"
+			: "%s %s must implement %d abstract private method%s (" MAX_ABSTRACT_INFO_FMT MAX_ABSTRACT_INFO_FMT MAX_ABSTRACT_INFO_FMT ")",
+			zend_get_object_type_uc(ce),
 			ZSTR_VAL(ce->name), ai.cnt,
 			ai.cnt > 1 ? "s" : "",
 			DISPLAY_ABSTRACT_FN(0),

Zend/zend_interfaces.c

@@ -266,7 +266,8 @@ static int zend_implement_traversable(zend_class_entry *interface, zend_class_en
 			}
 		}
 	}
-	zend_error_noreturn(E_CORE_ERROR, "Class %s must implement interface %s as part of either %s or %s",
+	zend_error_noreturn(E_CORE_ERROR, "%s %s must implement interface %s as part of either %s or %s",
+		zend_get_object_type_uc(class_type),
 		ZSTR_VAL(class_type->name),
 		ZSTR_VAL(zend_ce_traversable->name),
 		ZSTR_VAL(zend_ce_iterator->name),