Add #[NonpublicConstructor] attribute

Zend/tests/attributes/NonpublicConstructor/Generator.phpt

@@ -0,0 +1,13 @@
+--TEST--
+#[\NonpublicConstructor]: works as a replacement for get_constructor
+--FILE--
+<?php
+
+new Generator();
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Call to private Generator::__construct() from global scope, the "Generator" class is reserved for internal use and cannot be manually instantiated, in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d

Zend/tests/attributes/NonpublicConstructor/Reflection_newInstance.phpt

@@ -0,0 +1,20 @@
+--TEST--
+#[\NonpublicConstructor]: affects message from ReflectionClass::newInstance()
+--FILE--
+<?php
+
+class Demo {
+    #[\NonpublicConstructor("use ::getInstance() instead")]
+    private function __construct( $unused ) {}
+}
+
+$reflection = new ReflectionClass( Demo::class );
+$reflection->newInstance( true );
+
+?>
+--EXPECTF--
+Fatal error: Uncaught ReflectionException: Access to non-public constructor of class Demo, use ::getInstance() instead, in %s:%d
+Stack trace:
+#0 %s(%d): ReflectionClass->newInstance(true)
+#1 {main}
+  thrown in %s on line %d

Zend/tests/attributes/NonpublicConstructor/Reflection_newInstanceArgs.phpt

@@ -0,0 +1,20 @@
+--TEST--
+#[\NonpublicConstructor]: affects message from ReflectionClass::newInstanceArgs()
+--FILE--
+<?php
+
+class Demo {
+    #[\NonpublicConstructor("use ::getInstance() instead")]
+    private function __construct( $unused ) {}
+}
+
+$reflection = new ReflectionClass( Demo::class );
+$reflection->newInstanceArgs( [ true ] );
+
+?>
+--EXPECTF--
+Fatal error: Uncaught ReflectionException: Access to non-public constructor of class Demo, use ::getInstance() instead, in %s:%d
+Stack trace:
+#0 %s(%d): ReflectionClass->newInstanceArgs(Array)
+#1 {main}
+  thrown in %s on line %d

Zend/tests/attributes/NonpublicConstructor/as_object.phpt

@@ -0,0 +1,14 @@
+--TEST--
+#[\NonpublicConstructor]: using the attribute itself as an object
+--FILE--
+<?php
+
+$attrib = new NonpublicConstructor('example');
+var_dump( $attrib );
+
+?>
+--EXPECTF--
+object(NonpublicConstructor)#%d (1) {
+  ["message"]=>
+  string(7) "example"
+}

Zend/tests/attributes/NonpublicConstructor/global_private.phpt

@@ -0,0 +1,18 @@
+--TEST--
+#[\NonpublicConstructor]: affects error message (private constructor, global scope)
+--FILE--
+<?php
+
+class Demo {
+    #[\NonpublicConstructor("use ::getInstance() instead")]
+    private function __construct() {}
+}
+
+new Demo();
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Call to private Demo::__construct() from global scope, use ::getInstance() instead, in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %s

Zend/tests/attributes/NonpublicConstructor/global_protected.phpt

@@ -0,0 +1,18 @@
+--TEST--
+#[\NonpublicConstructor]: affects error message (protected constructor, global scope)
+--FILE--
+<?php
+
+class Demo {
+    #[\NonpublicConstructor("use ::getInstance() instead")]
+    protected function __construct() {}
+}
+
+new Demo();
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Call to protected Demo::__construct() from global scope, use ::getInstance() instead, in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %s

Zend/tests/attributes/NonpublicConstructor/must_be_constructor.phpt

@@ -0,0 +1,13 @@
+--TEST--
+#[\NonpublicConstructor]: On a private non-constructor
+--FILE--
+<?php
+
+class Demo {
+    #[\NonpublicConstructor]
+    private function test() {}
+}
+
+?>
+--EXPECTF--
+Fatal error: #[NonpublicConstructor] can only be applied to constructors in %s on line %d

Zend/tests/attributes/NonpublicConstructor/must_be_nonpublic.phpt

@@ -0,0 +1,13 @@
+--TEST--
+#[\NonpublicConstructor]: On a public constructor
+--FILE--
+<?php
+
+class Demo {
+    #[\NonpublicConstructor]
+    public function __construct() {}
+}
+
+?>
+--EXPECTF--
+Fatal error: #[NonpublicConstructor] can only be applied to protected or private constructors in %s on line %d

Zend/tests/attributes/NonpublicConstructor/non_string.phpt

@@ -0,0 +1,13 @@
+--TEST--
+#[\NonpublicConstructor]: Message argument must be a string
+--FILE--
+<?php
+
+class Demo {
+    #[\NonpublicConstructor(true)]
+    private function __construct() {}
+}
+
+?>
+--EXPECTF--
+Fatal error: NonpublicConstructor::__construct(): Argument #1 ($message) must be of type string, true given in %s on line %d

Zend/tests/attributes/NonpublicConstructor/subclass_private.phpt

@@ -0,0 +1,25 @@
+--TEST--
+#[\NonpublicConstructor]: affects error message (private constructor, protected scope)
+--FILE--
+<?php
+
+class Demo {
+    #[\NonpublicConstructor("use ::getInstance() instead")]
+    private function __construct() {}
+}
+
+class Subclass extends Demo {
+    public static function create() {
+        return new Demo();
+    }
+}
+
+Subclass::create();
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Call to private Demo::__construct() from scope Subclass, use ::getInstance() instead, in %s:%d
+Stack trace:
+#0 %s(%d): Subclass::create()
+#1 {main}
+  thrown in %s on line %s

Zend/tests/attributes/NonpublicConstructor/subclass_without_new.phpt

@@ -0,0 +1,25 @@
+--TEST--
+#[\NonpublicConstructor]: affects error message (private constructor, protected scope, called via `parent::__construct()`)
+--FILE--
+<?php
+
+class Demo {
+    #[\NonpublicConstructor("use ::getInstance() instead")]
+    private function __construct() {}
+}
+
+class Subclass extends Demo {
+    public function __construct() {
+        parent::__construct();
+    }
+}
+
+new Subclass();
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Cannot call private Demo::__construct(), use ::getInstance() instead, in %s:%d
+Stack trace:
+#0 %s(%d): Subclass->__construct()
+#1 {main}
+  thrown in %s on line %s

Zend/tests/attributes/NonpublicConstructor/without_message.phpt

@@ -0,0 +1,13 @@
+--TEST--
+#[\NonpublicConstructor]: Message argument is required
+--FILE--
+<?php
+
+class Demo {
+    #[\NonpublicConstructor]
+    private function __construct() {}
+}
+
+?>
+--EXPECTF--
+Fatal error: #[NonpublicConstructor] takes 1 parameter, 0 given in %s on line %d

Zend/tests/generators/errors/generator_instantiate_error.phpt

@@ -7,7 +7,7 @@ new Generator;
 
 ?>
 --EXPECTF--
-Fatal error: Uncaught Error: The "Generator" class is reserved for internal use and cannot be manually instantiated in %s:%d
+Fatal error: Uncaught Error: Call to private Generator::__construct() from global scope, the "Generator" class is reserved for internal use and cannot be manually instantiated, in %s:%d
 Stack trace:
 #0 {main}
   thrown in %s on line %d

Zend/zend_attributes.c

@@ -31,6 +31,7 @@ ZEND_API zend_class_entry *zend_ce_sensitive_parameter;
 ZEND_API zend_class_entry *zend_ce_sensitive_parameter_value;
 ZEND_API zend_class_entry *zend_ce_override;
 ZEND_API zend_class_entry *zend_ce_deprecated;
+ZEND_API zend_class_entry *zend_ce_nonpublic_constructor;
 
 static zend_object_handlers attributes_object_handlers_sensitive_parameter_value;
 
@@ -94,6 +95,110 @@ static void validate_allow_dynamic_properties(
 	scope->ce_flags |= ZEND_ACC_ALLOW_DYNAMIC_PROPERTIES;
 }
 
+static void validate_nonpublic_constructor(
+	zend_attribute *attr,
+	uint32_t target,
+	zend_class_entry *scope
+) {
+	zend_op_array *op_array = CG(active_op_array);
+	ZEND_ASSERT(op_array);
+
+	if (!(op_array->fn_flags & ZEND_ACC_CTOR)) {
+		zend_error_noreturn(
+			E_ERROR,
+			"#[NonpublicConstructor] can only be applied to constructors"
+		);
+	}
+	if (!(op_array->fn_flags & (ZEND_ACC_PROTECTED|ZEND_ACC_PRIVATE))) {
+		zend_error_noreturn(
+			E_ERROR,
+			"#[NonpublicConstructor] can only be applied to protected or private constructors"
+		);
+	}
+	if (attr->argc != 1) {
+		zend_error_noreturn(
+			E_ERROR,
+			"#[NonpublicConstructor] takes 1 parameter, %d given",
+			attr->argc
+		);
+	}
+	zval message;
+	if (FAILURE == zend_get_attribute_value(&message, attr, 0, NULL)) {
+		ZEND_ASSERT(EG(exception));
+		return;
+	}
+
+	if (Z_TYPE(message) != IS_STRING) {
+		zend_error_noreturn(
+			E_ERROR,
+			"NonpublicConstructor::__construct(): Argument #1 ($message) must be of type string, %s given",
+			zend_zval_value_name(&message)
+		);
+	}
+	zval_ptr_dtor(&message);
+}
+
+ZEND_API ZEND_COLD zend_result ZEND_FASTCALL zend_attribute_get_nonpublic_suffix(HashTable *attributes, zend_string **message_suffix)
+{
+	*message_suffix = ZSTR_EMPTY_ALLOC();
+
+	if (!attributes) {
+		return SUCCESS;
+	}
+
+	zend_attribute *nonpublicConstructor = zend_get_attribute_str(
+		attributes,
+		"nonpublicconstructor", 
+		sizeof("nonpublicconstructor")-1
+	);
+
+	if (!nonpublicConstructor) {
+		return SUCCESS;
+	}
+
+	ZEND_ASSERT(nonpublicConstructor->argc == 1);
+
+	zend_result result = FAILURE;
+	zend_string *message_prop = ZSTR_EMPTY_ALLOC();
+
+	zval obj;
+	ZVAL_UNDEF(&obj);
+	zval *z;
+
+	/* Construct the NonpublicConstructor object to correctly handle parameter processing. */
+	if (FAILURE == zend_get_attribute_object(
+		&obj,
+		zend_ce_nonpublic_constructor,
+		nonpublicConstructor,
+		NULL,
+		NULL
+	)) {
+		goto out;
+	}
+
+	/* Extract the $message property. */
+	z = zend_read_property_ex(zend_ce_nonpublic_constructor, Z_OBJ_P(&obj), ZSTR_KNOWN(ZEND_STR_MESSAGE), false, NULL);
+	ZEND_ASSERT(z != &EG(uninitialized_zval));
+	ZEND_ASSERT(Z_TYPE_P(z) == IS_STRING);
+	message_prop = zend_string_copy(Z_STR_P(z));
+
+	/* Construct the suffix. */
+	*message_suffix = zend_strpprintf_unchecked(
+		0,
+		", %S,",
+		message_prop
+	);
+
+	result = SUCCESS;
+
+ out:
+
+	zend_string_release(message_prop);
+	zval_ptr_dtor(&obj);
+
+	return result;
+}
+
 ZEND_METHOD(Attribute, __construct)
 {
 	zend_long flags = ZEND_ATTRIBUTE_TARGET_ALL;
@@ -193,6 +298,30 @@ ZEND_METHOD(Deprecated, __construct)
 	}
 }
 
+ZEND_METHOD(NonpublicConstructor, __construct)
+{
+	zend_string *message = NULL;
+
+	ZEND_PARSE_PARAMETERS_START(1, 1)
+		Z_PARAM_STR(message)
+	ZEND_PARSE_PARAMETERS_END();
+
+	zval messageValue;
+	ZVAL_STR(&messageValue, message);
+
+	zend_update_property_ex(
+		zend_ce_nonpublic_constructor,
+		Z_OBJ_P(ZEND_THIS),
+		ZSTR_KNOWN(ZEND_STR_MESSAGE),
+		&messageValue
+	);
+
+	/* The assignment might fail due to 'readonly'. */
+	if (UNEXPECTED(EG(exception))) {
+		RETURN_THROWS();
+	}
+}
+
 static zend_attribute *get_attribute(HashTable *attributes, zend_string *lcname, uint32_t offset)
 {
 	if (attributes) {
@@ -520,6 +649,10 @@ void zend_register_attribute_ce(void)
 
 	zend_ce_deprecated = register_class_Deprecated();
 	attr = zend_mark_internal_attribute(zend_ce_deprecated);
+
+	zend_ce_nonpublic_constructor = register_class_NonpublicConstructor();
+	attr = zend_mark_internal_attribute(zend_ce_nonpublic_constructor);
+	attr->validator = validate_nonpublic_constructor;
 }
 
 void zend_attributes_shutdown(void)