Start implementing intersection types

Author: Girgias

Zend/Optimizer/compact_literals.c

@@ -73,7 +73,7 @@ static size_t type_num_classes(const zend_op_array *op_array, uint32_t arg_num)
 		arg_info = op_array->arg_info - 1;
 	}
 
-	if (ZEND_TYPE_HAS_CLASS(arg_info->type)) {
+	if (ZEND_TYPE_IS_COMPLEX(arg_info->type)) {
 		if (ZEND_TYPE_HAS_LIST(arg_info->type)) {
 			return ZEND_TYPE_LIST(arg_info->type)->num_types;
 		}

Zend/Optimizer/dfa_pass.c

@@ -310,7 +310,7 @@ static inline bool can_elide_return_type_check(
 		return true;
 	}
 
-	if (disallowed_types == MAY_BE_OBJECT && use_info->ce && ZEND_TYPE_HAS_CLASS(arg_info->type)) {
+	if (disallowed_types == MAY_BE_OBJECT && use_info->ce && ZEND_TYPE_IS_COMPLEX(arg_info->type)) {
 		zend_type *single_type;
 		ZEND_TYPE_FOREACH(arg_info->type, single_type) {
 			if (ZEND_TYPE_HAS_NAME(*single_type)) {

Zend/Optimizer/zend_inference.c

@@ -2221,7 +2221,7 @@ static uint32_t zend_convert_type(const zend_script *script, zend_type type, zen
 	}
 
 	uint32_t tmp = zend_convert_type_declaration_mask(ZEND_TYPE_PURE_MASK(type));
-	if (ZEND_TYPE_HAS_CLASS(type)) {
+	if (ZEND_TYPE_IS_COMPLEX(type)) {
 		tmp |= MAY_BE_OBJECT;
 		if (pce) {
 			/* As we only have space to store one CE,

Zend/tests/type_declarations/intersection_types/added_interface_intersection_type.phpt

@@ -0,0 +1,53 @@
+--TEST--
+Added element of intersection type
+--FILE--
+<?php
+
+interface X {}
+interface Y {}
+interface Z {}
+
+class A implements X, Y, Z {}
+
+class Collection {
+    public X&Y $intersect;
+}
+
+function foo(): X&Y {
+    return new A();
+}
+
+function bar(X&Y $o): void {
+    var_dump($o);
+}
+
+try {
+    $o = foo();
+    var_dump($o);
+} catch (\TypeError $e) {
+    echo $e->getMessage(), "\n";
+}
+
+$c = new Collection();
+$a = new A();
+
+try {
+    $c->intersect = $a;
+    echo 'OK', \PHP_EOL;
+} catch (\TypeError $e) {
+    echo $e->getMessage(), "\n";
+}
+
+try {
+    bar($a);
+} catch (\TypeError $e) {
+    echo $e->getMessage(), "\n";
+}
+
+?>
+--EXPECT--
+object(A)#1 (0) {
+}
+OK
+object(A)#3 (0) {
+}

Zend/tests/type_declarations/intersection_types/assigning_intersection_types.phpt

@@ -0,0 +1,57 @@
+--TEST--
+Assigning values to intersection types
+--FILE--
+<?php
+
+interface X {}
+interface Y {}
+interface Z {}
+
+class TestParent implements X, Y {}
+class TestChild  extends TestParent implements Z {}
+
+class A {
+
+    public X&Y&Z $prop;
+
+    public function method1(X&Y $a): X&Y&Z {
+        return new TestChild();
+    }
+    public function method2(X $a): X&Y {
+        return new TestParent();
+    }
+}
+
+$tp = new TestParent();
+$tc = new TestChild();
+
+$o = new A();
+try {
+    $o->prop = $tp;
+} catch (TypeError $e) {
+    echo $e->getMessage(), \PHP_EOL;
+}
+
+$o->prop = $tc;
+
+$r = $o->method1($tp);
+var_dump($r);
+$r = $o->method2($tp);
+var_dump($r);
+$r = $o->method1($tc);
+var_dump($r);
+$r = $o->method2($tc);
+var_dump($r);
+
+
+?>
+--EXPECTF--
+Cannot assign TestParent to property A::$prop of type X&Y&Z
+object(TestChild)#%d (0) {
+}
+object(TestParent)#%d (0) {
+}
+object(TestChild)#%d (0) {
+}
+object(TestParent)#%d (0) {
+}

Zend/tests/type_declarations/intersection_types/invalid_types/invalid_array_type.phpt

@@ -0,0 +1,10 @@
+--TEST--
+array type cannot take part in an intersection type
+--FILE--
+<?php
+
+function foo(): array&Iterator {}
+
+?>
+--EXPECTF--
+Fatal error: Type array cannot be part of an intersection type in %s on line %d

Zend/tests/type_declarations/intersection_types/invalid_types/invalid_bool_type.phpt

@@ -0,0 +1,10 @@
+--TEST--
+bool type cannot take part in an intersection type
+--FILE--
+<?php
+
+function foo(): bool&Iterator {}
+
+?>
+--EXPECTF--
+Fatal error: Type bool cannot be part of an intersection type in %s on line %d

Zend/tests/type_declarations/intersection_types/invalid_types/invalid_callable_type.phpt

@@ -0,0 +1,10 @@
+--TEST--
+callable type cannot take part in an intersection type
+--FILE--
+<?php
+
+function foo(): callable&Iterator {}
+
+?>
+--EXPECTF--
+Fatal error: Type callable cannot be part of an intersection type in %s on line %d

Zend/tests/type_declarations/intersection_types/invalid_types/invalid_false_type.phpt

@@ -0,0 +1,10 @@
+--TEST--
+false type cannot take part in an intersection type
+--FILE--
+<?php
+
+function foo(): false&Iterator {}
+
+?>
+--EXPECTF--
+Fatal error: Type false cannot be part of an intersection type in %s on line %d

Zend/tests/type_declarations/intersection_types/invalid_types/invalid_float_type.phpt

@@ -0,0 +1,10 @@
+--TEST--
+float type cannot take part in an intersection type
+--FILE--
+<?php
+
+function foo(): float&Iterator {}
+
+?>
+--EXPECTF--
+Fatal error: Type float cannot be part of an intersection type in %s on line %d