[RFC] Friends

Zend/tests/friends/anonymous_class.phpt

@@ -0,0 +1,81 @@
+--TEST--
+Friends: anonymous classes can have friends
+--FILE--
+<?php
+
+class Bar {
+	public static function testAccess(object $obj) {
+		$obj::protectedStatic();
+		echo "\n";
+		$obj::privateStatic();
+		echo "\n";
+		$obj->protectedInstance();
+		echo "\n";
+		$obj->privateInstance();
+		echo "\n";
+		$obj->protectedProp = 1;
+		$obj->privateProp = 2;
+		var_dump($obj);
+		var_dump($obj::FIRST);
+		var_dump($obj::SECOND);
+	}
+}
+
+$obj = new class () {
+	friend Bar;
+
+	protected $protectedProp;
+	private $privateProp;
+
+	protected const FIRST = 1;
+	private const SECOND = 2;
+
+	protected static function protectedStatic() {
+		echo __METHOD__ . "() called, backtrace:\n";
+		debug_print_backtrace();
+	}
+
+	private static function privateStatic() {
+		echo __METHOD__ . "() called, backtrace:\n";
+		debug_print_backtrace();
+	}
+
+	protected function protectedInstance() {
+		echo __METHOD__ . "() called, backtrace:\n";
+		debug_print_backtrace();
+	}
+
+	private function privateInstance() {
+		echo __METHOD__ . "() called, backtrace:\n";
+		debug_print_backtrace();
+	}
+};
+
+Bar::testAccess($obj);
+
+?>
+--EXPECTF--
+class@anonymous%s:%d$0::protectedStatic() called, backtrace:
+#0 %s(%d): class@anonymous::protectedStatic()
+#1 %s(%d): Bar::testAccess(Object(class@anonymous))
+
+class@anonymous%s:%d$0::privateStatic() called, backtrace:
+#0 %s(%d): class@anonymous::privateStatic()
+#1 %s(%d): Bar::testAccess(Object(class@anonymous))
+
+class@anonymous%s:%d$0::protectedInstance() called, backtrace:
+#0 %s(%d): class@anonymous->protectedInstance()
+#1 %s(%d): Bar::testAccess(Object(class@anonymous))
+
+class@anonymous%s:%d$0::privateInstance() called, backtrace:
+#0 %s(%d): class@anonymous->privateInstance()
+#1 %s(%d): Bar::testAccess(Object(class@anonymous))
+
+object(class@anonymous)#1 (2) {
+  ["protectedProp":protected]=>
+  int(1)
+  ["privateProp":"class@anonymous":private]=>
+  int(2)
+}
+int(1)
+int(2)

Zend/tests/friends/ast_printing.phpt

@@ -0,0 +1,23 @@
+--TEST--
+Friends: AST printing
+--FILE--
+<?php
+
+try {
+    assert(function () {
+        class Foo {
+			friend Bar;
+        }
+    } && false);
+} catch (Error $e) {
+    echo $e->getMessage();
+}
+
+?>
+--EXPECT--
+assert(function () {
+    class Foo {
+        friend Bar;
+    }
+
+} && false)

Zend/tests/friends/clone_access.phpt

@@ -0,0 +1,48 @@
+--TEST--
+Friends: allows access to cloning
+--FILE--
+<?php
+
+class Foo {
+	friend Bar;
+
+	private function __clone() {
+		echo __METHOD__ . "() called, backtrace:\n";
+		debug_print_backtrace();
+	}
+
+}
+
+class Bar {
+	public static function testCloneAccess() {
+		$f = new Foo();
+		$g = clone $f;
+	}
+}
+
+// Confirm that the presence of a friend does not negate normal visibility
+// enforcement for non friends
+$f = new Foo();
+try {
+	clone $f;
+} catch (Error $e) {
+	echo $e . "\n";
+}
+
+echo "\n\n-----\n\n";
+
+// But friend works
+Bar::testCloneAccess();
+
+?>
+--EXPECTF--
+Error: Call to private method Foo::__clone() from global scope in %s:%d
+Stack trace:
+#0 {main}
+
+
+-----
+
+Foo::__clone() called, backtrace:
+#0 %s(%d): Foo->__clone()
+#1 %s(%d): Bar::testCloneAccess()

Zend/tests/friends/compiler_errors/interface_error.phpt

@@ -0,0 +1,12 @@
+--TEST--
+Friends: cannot be used on interfaces
+--FILE--
+<?php
+
+interface Foo {
+	friend Bar;
+}
+
+?>
+--EXPECTF--
+Fatal error: Cannot add friends to interfaces. Bar is used in Foo in %s on line %d

Zend/tests/friends/compiler_errors/repetition_basic.phpt

@@ -0,0 +1,13 @@
+--TEST--
+Friends: same friend cannot be used multiple times
+--FILE--
+<?php
+
+class Foo {
+	friend Bar;
+	friend Bar;
+}
+
+?>
+--EXPECTF--
+Fatal error: Cannot add Bar as a friend of Foo multiple times. in %s on line %d

Zend/tests/friends/compiler_errors/repetition_case_insensitive.phpt

@@ -0,0 +1,13 @@
+--TEST--
+Friends: same friend cannot be used multiple times (case insensitive)
+--FILE--
+<?php
+
+class Foo {
+	friend Bar;
+	friend BAR;
+}
+
+?>
+--EXPECTF--
+Fatal error: Cannot add BAR as a friend of Foo multiple times. in %s on line %d

Zend/tests/friends/compiler_errors/repetition_name_resolution.phpt

@@ -0,0 +1,16 @@
+--TEST--
+Friends: same friend cannot be used multiple times (after name resolution)
+--FILE--
+<?php
+
+use SomeNamespace\Bar;
+use SomeNamespace\Bar as Baz;
+
+class Foo {
+	friend Bar;
+	friend Baz;
+}
+
+?>
+--EXPECTF--
+Fatal error: Cannot add SomeNamespace\Bar as a friend of Foo multiple times. in %s on line %d

Zend/tests/friends/compiler_errors/reserved_parent.phpt

@@ -0,0 +1,12 @@
+--TEST--
+Friends: 'parent' cannot be used as a friend name
+--FILE--
+<?php
+
+class Foo {
+	friend parent;
+}
+
+?>
+--EXPECTF--
+Fatal error: Cannot use "parent" as friend name, as it is reserved in %s on line %d

Zend/tests/friends/compiler_errors/reserved_self.phpt

@@ -0,0 +1,12 @@
+--TEST--
+Friends: 'self' cannot be used as a friend name
+--FILE--
+<?php
+
+class Foo {
+	friend self;
+}
+
+?>
+--EXPECTF--
+Fatal error: Cannot use "self" as friend name, as it is reserved in %s on line %d

Zend/tests/friends/compiler_errors/reserved_static.phpt

@@ -0,0 +1,12 @@
+--TEST--
+Friends: 'static' cannot be used as a friend name
+--FILE--
+<?php
+
+class Foo {
+	friend static;
+}
+
+?>
+--EXPECTF--
+Fatal error: Cannot use "static" as friend name, as it is reserved in %s on line %d

Zend/tests/friends/compiler_errors/trait_error.phpt

@@ -0,0 +1,12 @@
+--TEST--
+Friends: cannot be used on traits
+--FILE--
+<?php
+
+trait Foo {
+	friend Bar;
+}
+
+?>
+--EXPECTF--
+Fatal error: Cannot add friends to traits. Bar is used in Foo in %s on line %d

Zend/tests/friends/constant_access.phpt

@@ -0,0 +1,53 @@
+--TEST--
+Friends: allows access to constants
+--FILE--
+<?php
+
+class Foo {
+	friend Bar;
+
+	protected const FIRST = 1;
+	private const SECOND = 2;
+}
+
+class Bar {
+	public static function testConstantAccess() {
+		var_dump(Foo::FIRST);
+		var_dump(Foo::SECOND);
+	}
+}
+
+// Confirm that the presence of a friend does not negate normal visibility
+// enforcement for non friends
+try {
+	var_dump(Foo::FIRST);
+} catch (Error $e) {
+	echo $e . "\n\n";
+}
+try {
+	var_dump(Foo::SECOND);
+} catch (Error $e) {
+	echo $e . "\n\n";
+}
+
+echo "\n\n-----\n\n";
+
+// But friend works
+Bar::testConstantAccess();
+
+?>
+--EXPECTF--
+Error: Cannot access protected constant Foo::FIRST in %s:%d
+Stack trace:
+#0 {main}
+
+Error: Cannot access private constant Foo::SECOND in %s:%d
+Stack trace:
+#0 {main}
+
+
+
+-----
+
+int(1)
+int(2)

Zend/tests/friends/constant_access_inherited.phpt

@@ -0,0 +1,40 @@
+--TEST--
+Friends: allows access to inherited non-overridden constants
+--FILE--
+<?php
+
+class Foo {
+	friend Bar;
+
+	protected const FIRST = 1;
+	protected const SECOND = 2;
+}
+
+class FooChild extends Foo {
+	protected const SECOND = 3;
+}
+
+class Bar {
+	public static function testConstantAccess() {
+		var_dump(FooChild::FIRST);
+
+		echo "\n";
+
+		try {
+			var_dump(FooChild::SECOND);
+		} catch (Error $e) {
+			echo $e . "\n\n";
+		}
+	}
+}
+
+Bar::testConstantAccess();
+
+?>
+--EXPECTF--
+int(1)
+
+Error: Cannot access protected constant FooChild::SECOND in %s:%d
+Stack trace:
+#0 %s(%d): Bar::testConstantAccess()
+#1 {main}