PFA rebinding validation

Author: arnaud-lb

Zend/tests/partial_application/rebinding_001.phpt

@@ -0,0 +1,65 @@
+--TEST--
+Partial application can only be rebound to an instanceof $this
+--FILE--
+<?php
+
+class C {
+    function f($a) { var_dump($this); }
+    static function g($a) { var_dump(static::class); }
+}
+
+class SubClass extends C {}
+
+class Unrelated {}
+
+$c = new C;
+$f = $c->f(?);
+$g = $c->g(?);
+
+echo "# Can be rebound to \$this of the same class:\n";
+$f->bindTo(new C)(1);
+
+echo "# Can be rebound to \$this of a sub-class:\n";
+$f->bindTo(new SubClass)(1);
+
+echo "# Cannot be rebound to an unrelated class:\n";
+try {
+    $f->bindTo(new Unrelated)(1);
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+
+echo "# Cannot unbind \$this on instance method:\n";
+try {
+    $f->bindTo(null)(1);
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+
+echo "# Can unbind \$this on static method:\n";
+try {
+    $g->bindTo(null)(1);
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+
+?>
+--EXPECTF--
+# Can be rebound to $this of the same class:
+object(C)#%d (0) {
+}
+# Can be rebound to $this of a sub-class:
+object(SubClass)#%d (0) {
+}
+# Cannot be rebound to an unrelated class:
+
+Warning: Cannot bind method C::f() to object of class Unrelated in %s on line %d
+Value of type null is not callable
+# Cannot unbind $this on instance method:
+
+Warning: Cannot unbind $this of method in %s on line %d
+Value of type null is not callable
+# Can unbind $this on static method:
+
+Warning: Cannot unbind $this of method in %s on line %d
+Value of type null is not callable

Zend/tests/partial_application/rebinding_002.phpt

@@ -0,0 +1,45 @@
+--TEST--
+Partial application scope cannot be rebound
+--FILE--
+<?php
+
+class C {
+    function f($a) { var_dump(static::class); }
+}
+
+class SubClass extends C {}
+
+function g($a) { var_dump(__FUNCTION__); }
+
+$c = new C;
+$f = $c->f(?);
+$g = g(?);
+
+echo "# Can be rebound to the same scope:\n";
+$f->bindTo($c, C::class)(1);
+
+echo "# Method cannot be rebound to a different scope:\n";
+try {
+    $f->bindTo($c, SubClass::class)(1);
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+
+echo "# Function cannot be refound to a different scope:\n";
+try {
+    $g->bindTo($c, SubClass::class)(1);
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+?>
+--EXPECTF--
+# Can be rebound to the same scope:
+string(1) "C"
+# Method cannot be rebound to a different scope:
+
+Warning: Cannot rebind scope of closure created from method in %s on line %d
+Value of type null is not callable
+# Function cannot be refound to a different scope:
+
+Warning: Cannot rebind scope of closure created from function in %s on line %d
+Value of type null is not callable

Zend/zend_closures.c

@@ -84,7 +84,8 @@ static bool zend_valid_closure_binding(
 		zend_closure *closure, zval *newthis, zend_class_entry *scope) /* {{{ */
 {
 	zend_function *func = &closure->func;
-	bool is_fake_closure = (func->common.fn_flags & ZEND_ACC_FAKE_CLOSURE) != 0;
+	bool is_fake_closure = (func->common.fn_flags & ZEND_ACC_FAKE_CLOSURE) != 0
+			|| (closure->closure_flags & ZEND_CLOSURE_PARTIAL);
 
 	if (newthis) {
 		if (func->common.fn_flags & ZEND_ACC_STATIC) {