[RFC] Implement structs (WIP)

Zend/tests/readonly_classes/readonly_enum.phpt

@@ -9,4 +9,4 @@ readonly enum Foo
 
 ?>
 --EXPECTF--
-Parse error: syntax error, unexpected token "enum", expecting "abstract" or "final" or "readonly" or "class" in %s on line %d
+Parse error: syntax error, unexpected token "enum" in %s on line %d

Zend/tests/readonly_classes/readonly_interface.phpt

@@ -9,4 +9,4 @@ readonly interface Foo
 
 ?>
 --EXPECTF--
-Parse error: syntax error, unexpected token "interface", expecting "abstract" or "final" or "readonly" or "class" in %s on line %d
+Parse error: syntax error, unexpected token "interface" in %s on line %d

Zend/tests/readonly_classes/readonly_trait.phpt

@@ -9,4 +9,4 @@ readonly trait Foo
 
 ?>
 --EXPECTF--
-Parse error: syntax error, unexpected token "trait", expecting "abstract" or "final" or "readonly" or "class" in %s on line %d
+Parse error: syntax error, unexpected token "trait" in %s on line %d

Zend/tests/structs/abstract.phpt

@@ -0,0 +1,10 @@
+--TEST--
+Structs must not be marked as abstract
+--FILE--
+<?php
+
+abstract struct Box {}
+
+?>
+--EXPECTF--
+Fatal error: Cannot use the abstract modifier on a struct, as structs are implicitly final in %s on line %d

Zend/tests/structs/array_access.phpt

@@ -0,0 +1,111 @@
+--TEST--
+Structs implementing ArrayAccess
+--FILE--
+<?php
+
+abstract class VectorBase implements ArrayAccess {
+    public $elements;
+
+    public function offsetExists(mixed $offset): bool {
+        return array_key_exists($offset, $this->elements);
+    }
+
+    public function offsetSet(mixed $offset, mixed $value): void {
+        if ($offset) {
+            $this->elements[$offset] = $value;
+        } else {
+            $this->elements[] = $value;
+        }
+    }
+
+    public function offsetUnset(mixed $offset): void {
+        unset($this->elements[$offset]);
+    }
+}
+
+struct VectorByVal extends VectorBase {
+    public function offsetGet(mixed $offset): mixed {
+        return $this->elements[$offset];
+    }
+}
+
+struct VectorByRef extends VectorBase {
+    public function &offsetGet(mixed $offset): mixed {
+        return $this->elements[$offset];
+    }
+}
+
+struct Box {
+    public function __construct(
+        public int $value,
+    ) {}
+
+    public mutating function inc() {
+        $this->value++;
+    }
+}
+
+$box = new Box(1);
+
+$vec = new VectorByVal();
+$vec[] = $box;
+$vec[0]->value = 2;
+var_dump($vec);
+$vec[0]->inc!();
+var_dump($vec);
+
+$vec = new VectorByRef();
+$vec[] = $box;
+$vec[0]->value = 2;
+var_dump($vec);
+$vec[0]->inc!();
+var_dump($vec);
+
+var_dump($box);
+
+?>
+--EXPECT--
+object(VectorByVal)#2 (1) {
+  ["elements"]=>
+  array(1) {
+    [0]=>
+    object(Box)#1 (1) {
+      ["value"]=>
+      int(1)
+    }
+  }
+}
+object(VectorByVal)#2 (1) {
+  ["elements"]=>
+  array(1) {
+    [0]=>
+    object(Box)#1 (1) {
+      ["value"]=>
+      int(1)
+    }
+  }
+}
+object(VectorByRef)#3 (1) {
+  ["elements"]=>
+  array(1) {
+    [0]=>
+    object(Box)#2 (1) {
+      ["value"]=>
+      int(2)
+    }
+  }
+}
+object(VectorByRef)#3 (1) {
+  ["elements"]=>
+  array(1) {
+    [0]=>
+    object(Box)#2 (1) {
+      ["value"]=>
+      int(3)
+    }
+  }
+}
+object(Box)#1 (1) {
+  ["value"]=>
+  int(1)
+}

Zend/tests/structs/assign_op.phpt

@@ -0,0 +1,27 @@
+--TEST--
+Assign op on structs
+--FILE--
+<?php
+
+struct Box {
+    public function __construct(
+        public $value,
+    ) {}
+}
+
+$a = new Box(0);
+$b = $a;
+$b->value += 1;
+var_dump($a);
+var_dump($b);
+
+?>
+--EXPECT--
+object(Box)#1 (1) {
+  ["value"]=>
+  int(0)
+}
+object(Box)#2 (1) {
+  ["value"]=>
+  int(1)
+}

Zend/tests/structs/assign_ref.phpt

@@ -0,0 +1,27 @@
+--TEST--
+Assign ref on structs
+--FILE--
+<?php
+
+struct Box {
+    public $value;
+}
+
+$a = new Box();
+$a->value = 1;
+$b = $a;
+$c = 2;
+$b->value = &$c;
+var_dump($a);
+var_dump($b);
+
+?>
+--EXPECT--
+object(Box)#1 (1) {
+  ["value"]=>
+  int(1)
+}
+object(Box)#2 (1) {
+  ["value"]=>
+  &int(2)
+}

Zend/tests/structs/assign_to_self.phpt

@@ -0,0 +1,32 @@
+--TEST--
+Send structs
+--FILE--
+<?php
+
+struct Box {
+    public function __construct(
+        public $value,
+    ) {}
+}
+
+$a = new Box(42);
+$a->value = $a;
+var_dump($a);
+
+$b = new Box(42);
+$b->value = &$b;
+var_dump($b);
+
+?>
+--EXPECT--
+object(Box)#2 (1) {
+  ["value"]=>
+  object(Box)#1 (1) {
+    ["value"]=>
+    int(42)
+  }
+}
+object(Box)#3 (1) {
+  ["value"]=>
+  *RECURSION*
+}

Zend/tests/structs/basic.phpt

@@ -0,0 +1,33 @@
+--TEST--
+Basic structs
+--FILE--
+<?php
+
+struct Point {
+    public function __construct(
+        public int $x,
+        public int $y,
+    ) {}
+}
+
+$a = new Point(1, 1);
+$b = $a;
+$b->x = 2;
+$b->y = 2;
+var_dump($a);
+var_dump($b);
+
+?>
+--EXPECT--
+object(Point)#1 (2) {
+  ["x"]=>
+  int(1)
+  ["y"]=>
+  int(1)
+}
+object(Point)#2 (2) {
+  ["x"]=>
+  int(2)
+  ["y"]=>
+  int(2)
+}

Zend/tests/structs/final.phpt

@@ -0,0 +1,10 @@
+--TEST--
+Structs must not be marked as final
+--FILE--
+<?php
+
+final struct Box {}
+
+?>
+--EXPECTF--
+Fatal error: Cannot use the final modifier on a struct, as structs are implicitly final in %s on line %d

Zend/tests/structs/interior_immutability.phpt

@@ -0,0 +1,43 @@
+--TEST--
+Basic structs
+--FILE--
+<?php
+
+struct Child {
+    public function __construct(
+        public $value,
+    ) {}
+}
+
+class Parent_ {
+    public function __construct(
+        public Child $writableChild,
+        public readonly Child $readonlyChild,
+    ) {}
+}
+
+$parent = new Parent_(new Child(1), new Child(1));
+$parent->writableChild->value = 2;
+try {
+    $parent->readonlyChild->value = 2;
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+
+var_dump($parent);
+
+?>
+--EXPECTF--
+Cannot indirectly modify readonly property Parent_::$readonlyChild
+object(Parent_)#1 (2) {
+  ["writableChild"]=>
+  object(Child)#%d (1) {
+    ["value"]=>
+    int(2)
+  }
+  ["readonlyChild"]=>
+  object(Child)#%d (1) {
+    ["value"]=>
+    int(1)
+  }
+}

Zend/tests/structs/is_identical.phpt

@@ -0,0 +1,73 @@
+--TEST--
+=== on structs
+--FILE--
+<?php
+
+struct Box {
+    public function __construct(
+        public $value,
+    ) {}
+}
+
+$a = new Box(1);
+$b = new Box(2);
+$c = $a;
+$d = $a;
+$d->value++;
+$e = new Box('1');
+
+$values = [$a, $b, $c, $d, $e];
+foreach ($values as $l) {
+    foreach ($values as $r) {
+        echo var_export($l->value, true)
+            . ' === '
+            . var_export($r->value, true)
+            . ' => '
+            . ($l === $r ? 'true' : 'false')
+            . "\n";
+    }
+}
+
+#[\AllowDynamicProperties]
+struct Point {}
+
+$a = new Point();
+$a->x = 1;
+$a->y = 1;
+$b = new Point();
+$b->y = 1;
+$b->x = 1;
+var_dump($a === $b);
+unset($b->y);
+$b->y = 1;
+var_dump($a === $b);
+
+?>
+--EXPECT--
+1 === 1 => true
+1 === 2 => false
+1 === 1 => true
+1 === 2 => false
+1 === '1' => false
+2 === 1 => false
+2 === 2 => true
+2 === 1 => false
+2 === 2 => true
+2 === '1' => false
+1 === 1 => true
+1 === 2 => false
+1 === 1 => true
+1 === 2 => false
+1 === '1' => false
+2 === 1 => false
+2 === 2 => true
+2 === 1 => false
+2 === 2 => true
+2 === '1' => false
+'1' === 1 => false
+'1' === 2 => false
+'1' === 1 => false
+'1' === 2 => false
+'1' === '1' => true
+bool(false)
+bool(true)