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nikicnikic
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Add support for $obj::class
This allows $obj::class, which gives the same result as get_class($obj). Anything other than an object results in TypeError. RFC: https://wiki.php.net/rfc/class_name_literal_on_object Closes GH-5065.
1 parent 69819ba commit d933591

11 files changed

+940
-701
lines changed

‎UPGRADING‎

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Original file line numberDiff line numberDiff line change
@@ -367,6 +367,9 @@ PHP 8.0 UPGRADE NOTES
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class B extends A {
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public function method(...$everything) {}
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}
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. It is now possible to fetch the class name of an object using
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`$object::class`. The result is the same as `get_class($object)`.
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RFC: https://wiki.php.net/rfc/class_name_literal_on_object
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- Date:

‎Zend/tests/class_name_of_var.phpt‎

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This file was deleted.

‎Zend/tests/class_on_constant_evaluated_expression.phpt‎

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,10 @@
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--TEST--
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An error should be generated when using ::class on a constant evaluated expression
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--FILE--
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<?php
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(1+1)::class;
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?>
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--EXPECTF--
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Fatal error: Cannot use ::class on value of type int in %s on line %d

‎Zend/tests/class_on_expression_in_constant_expression.phpt‎

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@@ -0,0 +1,10 @@
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--TEST--
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::class on an expression cannot be used inside constant expressions
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--FILE--
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<?php
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const A = [0]::class;
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?>
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--EXPECTF--
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Fatal error: (expression)::class cannot be used in constant expressions in %s on line %d

‎Zend/tests/class_on_object.phpt‎

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,28 @@
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--TEST--
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Using ::class on an object
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--FILE--
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<?php
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$obj = new stdClass;
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var_dump($obj::class);
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$ref =& $obj;
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var_dump($ref::class);
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var_dump((new stdClass)::class);
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// Placed in a function to check that opcache doesn't perform incorrect constprop.
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function test() {
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$other = null;
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var_dump($other::class);
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}
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try {
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test();
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} catch (TypeError $e) {
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echo $e->getMessage(), "\n";
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}
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?>
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--EXPECT--
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string(8) "stdClass"
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string(8) "stdClass"
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string(8) "stdClass"
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Cannot use ::class on value of type null

‎Zend/zend_compile.c‎

Lines changed: 21 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -1551,7 +1551,7 @@ static zend_bool zend_try_compile_const_expr_resolve_class_name(zval *zv, zend_a
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zval *class_name;
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15531553
if (class_ast->kind != ZEND_AST_ZVAL) {
1554-
zend_error_noreturn(E_COMPILE_ERROR, "Cannot use ::class with dynamic class name");
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return 0;
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}
15561556

15571557
class_name = zend_ast_get_zval(class_ast);
@@ -8246,15 +8246,27 @@ void zend_compile_class_const(znode *result, zend_ast *ast) /* {{{ */
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void zend_compile_class_name(znode *result, zend_ast *ast) /* {{{ */
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{
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zend_ast *class_ast = ast->child[0];
8249-
zend_op *opline;
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82518250
if (zend_try_compile_const_expr_resolve_class_name(&result->u.constant, class_ast)) {
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result->op_type = IS_CONST;
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return;
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}
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8256-
opline = zend_emit_op_tmp(result, ZEND_FETCH_CLASS_NAME, NULL, NULL);
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opline->op1.num = zend_get_class_fetch_type(zend_ast_get_str(class_ast));
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if (class_ast->kind == ZEND_AST_ZVAL) {
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zend_op *opline = zend_emit_op_tmp(result, ZEND_FETCH_CLASS_NAME, NULL, NULL);
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opline->op1.num = zend_get_class_fetch_type(zend_ast_get_str(class_ast));
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} else {
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znode expr_node;
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zend_compile_expr(&expr_node, class_ast);
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if (expr_node.op_type == IS_CONST) {
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/* Unlikely case that happen if class_ast is constant folded.
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* Handle it here, to avoid needing a CONST specialization in the VM. */
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zend_error_noreturn(E_COMPILE_ERROR, "Cannot use ::class on value of type %s",
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zend_get_type_by_const(Z_TYPE(expr_node.u.constant)));
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}
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zend_emit_op_tmp(result, ZEND_FETCH_CLASS_NAME, &expr_node, NULL);
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}
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}
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/* }}} */
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@@ -8491,6 +8503,11 @@ void zend_compile_const_expr_class_name(zend_ast **ast_ptr) /* {{{ */
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{
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zend_ast *ast = *ast_ptr;
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zend_ast *class_ast = ast->child[0];
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if (class_ast->kind != ZEND_AST_ZVAL) {
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zend_error_noreturn(E_COMPILE_ERROR,
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"(expression)::class cannot be used in constant expressions");
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}
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84948511
zend_string *class_name = zend_ast_get_str(class_ast);
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uint32_t fetch_type = zend_get_class_fetch_type(class_name);
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‎Zend/zend_vm_def.h‎

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Original file line numberDiff line numberDiff line change
@@ -7992,14 +7992,32 @@ ZEND_VM_HANDLER(151, ZEND_ASSERT_CHECK, ANY, JMP_ADDR)
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}
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}
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7995-
ZEND_VM_HANDLER(157, ZEND_FETCH_CLASS_NAME, UNUSED|CLASS_FETCH, ANY)
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ZEND_VM_HANDLER(157, ZEND_FETCH_CLASS_NAME, CV|TMPVAR|UNUSED|CLASS_FETCH, ANY)
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{
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uint32_t fetch_type;
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zend_class_entry *called_scope, *scope;
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USE_OPLINE
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8001-
fetch_type = opline->op1.num;
8001+
if (OP1_TYPE != IS_UNUSED) {
8002+
zval *op = GET_OP1_ZVAL_PTR(BP_VAR_R);
8003+
SAVE_OPLINE();
8004+
if (UNEXPECTED(Z_TYPE_P(op) != IS_OBJECT)) {
8005+
ZVAL_DEREF(op);
8006+
if (Z_TYPE_P(op) != IS_OBJECT) {
8007+
zend_type_error("Cannot use ::class on value of type %s",
8008+
zend_get_type_by_const(Z_TYPE_P(op)));
8009+
ZVAL_UNDEF(EX_VAR(opline->result.var));
8010+
FREE_OP1();
8011+
HANDLE_EXCEPTION();
8012+
}
8013+
}
80028014

8015+
ZVAL_STR_COPY(EX_VAR(opline->result.var), Z_OBJCE_P(op)->name);
8016+
FREE_OP1();
8017+
ZEND_VM_NEXT_OPCODE_CHECK_EXCEPTION();
8018+
}
8019+
8020+
fetch_type = opline->op1.num;
80038021
scope = EX(func)->op_array.scope;
80048022
if (UNEXPECTED(scope == NULL)) {
80058023
SAVE_OPLINE();

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