test: add valid php 8.1 example class

tests/ValidPhp81Class.php

+<?php
+
+use N\{ClassName,
+    AnotherClassName,
+    OneMoreClassName
+};
+
+$instance = new class {
+};
+
+namespace A {
+
+    #[Attribute] #[Attribute(1, 2)] function foo()
+    {
+        return 0;
+    }
+
+    function bar(
+        $x,
+        $y,
+        int $z = 1
+    ) {
+        $x = 0;
+// $x = 1
+        do {
+            $y += 1;
+        } while ($y < 10);
+        if (true) {
+            $x = 10;
+        } elseif ($y < 10) {
+            $x = 5;
+        } elseif (true) {
+            $x = 5;
+        }
+        for ($i = 0; $i < 10; $i++) {
+            $yy = $x > 2 ? 1 : 2;
+        }
+        while (true) {
+            $x = 0;
+        }
+        do {
+            $x += 1;
+        } while (true);
+        foreach (
+            array(
+                "a" => 0,
+                "b" => 1,
+                "c" => 2
+            ) as $e1
+        ) {
+            echo $e1;
+        }
+        $count = 10;
+        $x = array(
+            "x",
+            "y",
+            array(
+                1 => "abc",
+                2 => "def",
+                3 => "ghi"
+            )
+        );
+        $zz = array(
+            0.1,
+            0.2,
+            0.3,
+            0.4
+        );
+        $x = array(
+            0 => "zero",
+            123 => "one two three",
+            25 => "two five"
+        );
+        bar(
+            0,
+            bar(
+                1,
+                "b"
+            )
+        );
+    }
+
+    abstract class Foo extends
+        FooBaseClass implements Bar1,
+                                Bar2,
+                                Bar3
+    {
+
+        var $numbers = array(
+            "one",
+            "two",
+            "three",
+            "four",
+            "five",
+            "six"
+        );
+        var $v = 0; // comment 
+        public $path = "root"; // comment
+
+        const FIRST = 'first';
+        const SECOND = 0;
+        const Z = -1;
+
+        function bar(
+            $v,
+            $w = "a"
+        ) {
+            $y = $w;
+            $result = foo(
+                "arg1",
+                "arg2",
+                10
+            );
+            switch ($v) {
+                case 0:
+                    return 1;
+                case 1:
+                    echo '1';
+                    break;
+                case 2:
+                    break;
+                default:
+                    $result = 10;
+            }
+            return $result;
+        }
+
+        public static function fOne(
+            #[Attribute(1, 2)] $argA,
+            $argB,
+            $argC,
+            $argD,
+            $argE,
+            $argF,
+            $argG,
+            $argH
+        ) {
+            $x = $argA + $argB + $argC + $argD + $argE + $argF + $argG + $argH;
+            list($field1, $field2, $field3, $filed4, $field5, $field6) = explode(
+                ",",
+                $x
+            );
+            fTwo(
+                $argA,
+                $argB,
+                $argC,
+                fThree(
+                    $argD,
+                    $argE,
+                    $argF,
+                    $argG,
+                    $argH
+                )
+            );
+            $z = $argA == "Some string" ? "yes" : "no";
+            $colors = array(
+                "red",
+                "green",
+                "blue",
+                "black",
+                "white",
+                "gray"
+            );
+            $count = count($colors);
+            for ($i = 0; $i < $count; $i++) {
+                $colorString = $colors[$i];
+            }
+        }
+
+        function fTwo(
+            $strA,
+            $strB,
+            $strC,
+            $strD
+        ) {
+            if ($strA == "one" || $strB == "two" || $strC == "three") {
+                return $strA + $strB + $strC;
+            }
+            $x = $foo->one(
+                "a",
+                "b"
+            )->two(
+                "c",
+                "d",
+                "e"
+            )->three("fg")->four();
+            $y = a()->b()->c();
+            return $strD;
+        }
+
+        function fThree(
+            $strA,
+            $strB,
+            $strC,
+            $strD,
+            $strE
+        ) {
+            try {
+            } catch (Exception $e) {
+                foo();
+            } finally {
+                // do something
+            }
+            return $strA + $strB + $strC + $strD + $strE;
+        }
+
+        protected abstract function fFour();
+
+    }
+}
+function f($a, $ab, $abc)
+{
+}
+
+f(
+    a: 1,
+    ab: 2,
+    abc: 3
+);
+$j = 0;
+
+function f2(array $arr)
+{
+}
+
+f2([
+    0 => 5,
+    1 => 7,
+]);
+
+echo match ($j) {
+    0 => 'zero',
+    2 => 'two',
+    42 => 'forty-two',
+    default => throw new Exception()
+};
+
+enum Suit: string
+{
+    case Clubs = 'C';
+    case Diamonds = 'D';
+    case Hearts = 'H';
+    case Spades = 'S';
+}