Implement enums

RFC: https://wiki.php.net/rfc/enumerations

Co-authored-by: Larry Garfield <larry@garfieldtech.com>

Closes GH-6489.

Author: iluuu1994

Zend/tests/enum/__call.phpt

@@ -0,0 +1,29 @@
+--TEST--
+Enum __call
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+
+    public function __call(string $name, array $args)
+    {
+        return [$name, $args];
+    }
+}
+
+var_dump(Foo::Bar->baz('qux', 'quux'));
+
+?>
+--EXPECT--
+array(2) {
+  [0]=>
+  string(3) "baz"
+  [1]=>
+  array(2) {
+    [0]=>
+    string(3) "qux"
+    [1]=>
+    string(4) "quux"
+  }
+}

Zend/tests/enum/__class__.phpt

@@ -0,0 +1,19 @@
+--TEST--
+Enum __CLASS__
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+
+    public function printClass()
+    {
+        echo __CLASS__ . "\n";
+    }
+}
+
+Foo::Bar->printClass();
+
+?>
+--EXPECT--
+Foo

Zend/tests/enum/__function__.phpt

@@ -0,0 +1,19 @@
+--TEST--
+Enum __FUNCTION__
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+
+    public function printFunction()
+    {
+        echo __FUNCTION__ . "\n";
+    }
+}
+
+Foo::Bar->printFunction();
+
+?>
+--EXPECT--
+printFunction

Zend/tests/enum/__get.phpt

@@ -0,0 +1,21 @@
+--TEST--
+Enum __get
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+
+    public function __get(string $name): string
+    {
+        return '__get ' . $name . "\n";
+    }
+}
+
+echo Foo::Bar->baz;
+echo Foo::Bar->qux;
+
+?>
+--EXPECT--
+__get baz
+__get qux

Zend/tests/enum/__invoke.phpt

@@ -0,0 +1,24 @@
+--TEST--
+Enum __invoke
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+
+    public function __invoke(...$args)
+    {
+        return $args;
+    }
+}
+
+var_dump((Foo::Bar)('baz', 'qux'));
+
+?>
+--EXPECT--
+array(2) {
+  [0]=>
+  string(3) "baz"
+  [1]=>
+  string(3) "qux"
+}

Zend/tests/enum/basic-methods.phpt

@@ -0,0 +1,21 @@
+--TEST--
+Enum methods
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+
+    public function dump() {
+        var_dump($this);
+    }
+}
+
+Foo::Bar->dump();
+Foo::Baz->dump();
+
+?>
+--EXPECT--
+enum(Foo::Bar)
+enum(Foo::Baz)

Zend/tests/enum/case-attributes.phpt

@@ -0,0 +1,25 @@
+--TEST--
+Enum case attributes
+--FILE--
+<?php
+
+#[Attribute]
+class EnumCaseAttribute {
+    public function __construct(
+        public string $value,
+    ) {}
+}
+
+enum Foo {
+    #[EnumCaseAttribute('Bar')]
+    case Bar;
+}
+
+var_dump((new \ReflectionClassConstant(Foo::class, 'Bar'))->getAttributes(EnumCaseAttribute::class)[0]->newInstance());
+
+?>
+--EXPECT--
+object(EnumCaseAttribute)#1 (1) {
+  ["value"]=>
+  string(3) "Bar"
+}

Zend/tests/enum/comparison.phpt

@@ -0,0 +1,30 @@
+--TEST--
+Enum comparison
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+    case Baz;
+}
+
+$bar = Foo::Bar;
+$baz = Foo::Baz;
+
+var_dump($bar === $bar);
+var_dump($bar == $bar);
+
+var_dump($bar === $baz);
+var_dump($bar == $baz);
+
+var_dump($baz === $bar);
+var_dump($baz == $bar);
+
+?>
+--EXPECT--
+bool(true)
+bool(true)
+bool(false)
+bool(false)
+bool(false)
+bool(false)

Zend/tests/enum/constant-aliases.phpt

@@ -0,0 +1,21 @@
+--TEST--
+Enum constants can alias cases
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+    const Baz = self::Bar;
+}
+
+function test(Foo $var) {
+    echo "works\n";
+}
+
+test(Foo::Bar);
+test(Foo::Baz);
+
+?>
+--EXPECT--
+works
+works

Zend/tests/enum/constants.phpt

@@ -0,0 +1,14 @@
+--TEST--
+Enum allows constants
+--FILE--
+<?php
+
+enum Foo {
+    const BAR = 'Bar';
+}
+
+echo Foo::BAR . "\n";
+
+?>
+--EXPECT--
+Bar

Zend/tests/enum/default-parameter.phpt

@@ -0,0 +1,18 @@
+--TEST--
+Enum in default parameter
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+}
+
+function baz(Foo $foo = Foo::Bar) {
+    var_dump($foo);
+}
+
+baz();
+
+?>
+--EXPECT--
+enum(Foo::Bar)

Zend/tests/enum/enum-as-constant.phpt

@@ -0,0 +1,22 @@
+--TEST--
+Enum cases can be referenced by constants
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+}
+
+const Beep = Foo::Bar;
+
+class Test {
+    const Beep = Foo::Bar;
+}
+
+var_dump(Beep);
+var_dump(Test::Beep);
+
+?>
+--EXPECT--
+enum(Foo::Bar)
+enum(Foo::Bar)

Zend/tests/enum/enum-as-params.phpt

@@ -0,0 +1,35 @@
+--TEST--
+Enum types as parameters
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+}
+
+enum Baz {
+    case Qux;
+}
+
+function takesFoo(Foo $foo) {}
+function takesBaz(Baz $baz) {}
+
+takesFoo(Foo::Bar);
+takesBaz(Baz::Qux);
+
+try {
+    takesBaz(Foo::Bar);
+} catch (Error $e) {
+    echo $e->getMessage() . "\n";
+}
+
+try {
+    takesFoo(Baz::Qux);
+} catch (Error $e) {
+    echo $e->getMessage() . "\n";
+}
+
+?>
+--EXPECTF--
+takesBaz(): Argument #1 ($baz) must be of type Baz, Foo given, called in %s on line %d
+takesFoo(): Argument #1 ($foo) must be of type Foo, Baz given, called in %s on line %d

Zend/tests/enum/enum-attributes.phpt

@@ -0,0 +1,23 @@
+--TEST--
+Enum attributes
+--FILE--
+<?php
+
+#[Attribute]
+class EnumAttribute {
+    public function __construct(
+        public string $value,
+    ) {}
+}
+
+#[EnumAttribute('Foo')]
+enum Foo {}
+
+var_dump((new \ReflectionClass(Foo::class))->getAttributes(EnumAttribute::class)[0]->newInstance());
+
+?>
+--EXPECT--
+object(EnumAttribute)#1 (1) {
+  ["value"]=>
+  string(3) "Foo"
+}

Zend/tests/enum/enum-in-constant.phpt

@@ -0,0 +1,22 @@
+--TEST--
+Enum in constant
+--FILE--
+<?php
+
+enum Foo {
+    case Bar;
+}
+
+class Baz {
+    const BAR = Foo::Bar;
+}
+
+var_dump(Foo::Bar);
+var_dump(Baz::BAR);
+var_dump(Foo::Bar === Baz::BAR);
+
+?>
+--EXPECT--
+enum(Foo::Bar)
+enum(Foo::Bar)
+bool(true)

Zend/tests/enum/final.phpt

@@ -0,0 +1,12 @@
+--TEST--
+Enum is final
+--FILE--
+<?php
+
+enum Foo {}
+
+class Bar extends Foo {}
+
+?>
+--EXPECTF--
+Fatal error: Class Bar may not inherit from final class (Foo) in %s on line %d