Allow null and false in union type for typed properties

src/main/php/PDepend/Source/Language/PHP/PHPParserVersion74.php

@@ -57,20 +57,22 @@
  */
 abstract class PHPParserVersion74 extends PHPParserVersion73
 {
+    protected $possiblePropertyTypes = array(
+        Tokens::T_STRING,
+        Tokens::T_ARRAY,
+        Tokens::T_QUESTION_MARK,
+        Tokens::T_BACKSLASH,
+        Tokens::T_CALLABLE,
+        Tokens::T_SELF,
+    );
+
     protected function parseUnknownDeclaration($tokenType, $modifiers)
     {
         /**
          * Typed properties
          * https://www.php.net/manual/en/migration74.new-features.php#migration74.new-features.core.typed-properties
          */
-        if (in_array($tokenType, array(
-            Tokens::T_STRING,
-            Tokens::T_ARRAY,
-            Tokens::T_QUESTION_MARK,
-            Tokens::T_BACKSLASH,
-            Tokens::T_CALLABLE,
-            Tokens::T_SELF,
-        ))) {
+        if (in_array($tokenType, $this->possiblePropertyTypes, true)) {
             $type = $this->parseTypeHint();
             $declaration = $this->parseFieldDeclaration();
             $declaration->prependChild($type);

src/main/php/PDepend/Source/Language/PHP/PHPParserVersion80.php

@@ -67,6 +67,17 @@
  */
 abstract class PHPParserVersion80 extends PHPParserVersion74
 {
+    protected $possiblePropertyTypes = array(
+        Tokens::T_STRING,
+        Tokens::T_ARRAY,
+        Tokens::T_QUESTION_MARK,
+        Tokens::T_BACKSLASH,
+        Tokens::T_CALLABLE,
+        Tokens::T_SELF,
+        Tokens::T_NULL,
+        Tokens::T_FALSE,
+    );
+
     /**
      * Will return <b>true</b> if the given <b>$tokenType</b> is a valid class
      * name part.

src/test/php/PDepend/Source/Language/PHP/PHPParserVersion80Test.php

@@ -41,6 +41,8 @@
 namespace PDepend\Source\Language\PHP;
 
 use PDepend\AbstractTest;
+use PDepend\Source\AST\ASTClass;
+use PDepend\Source\AST\ASTFieldDeclaration;
 use PDepend\Source\Builder\Builder;
 use PDepend\Source\Tokenizer\Tokenizer;
 use PDepend\Util\Cache\CacheDriver;
@@ -128,6 +130,45 @@ public function testTrailingCommaInParameterList()
         $this->assertCount(2, $method->getParameters());
     }
 
+    public function testNullableTypedProperties()
+    {
+        /** @var ASTClass $class */
+        $class = $this->getFirstClassForTestCase();
+        $children = $class->getChildren();
+
+        $this->assertTrue($children[0]->hasType());
+
+        /** @var array[] $declarations */
+        $declarations = array_map(function (ASTFieldDeclaration $child) {
+            $childChildren = $child->getChildren();
+
+            return array(
+                $child->hasType() ? $child->getType() : null,
+                $childChildren[1],
+            );
+        }, $children);
+
+        foreach (array(
+            array('null|int|float', '$number', 'PDepend\\Source\\AST\\ASTUnionType'),
+        ) as $index => $expected) {
+            list($expectedType, $expectedVariable, $expectedTypeClass) = $expected;
+            list($type, $variable) = $declarations[$index];
+
+            $this->assertInstanceOf(
+                $expectedTypeClass,
+                $type,
+                "Wrong type for $expectedType $expectedVariable"
+            );
+            $this->assertSame(ltrim($expectedType, '?'), $type->getImage());
+            $this->assertInstanceOf(
+                'PDepend\\Source\\AST\\ASTVariableDeclarator',
+                $variable,
+                "Wrong variable for $expectedType $expectedVariable"
+            );
+            $this->assertSame($expectedVariable, $variable->getImage());
+        }
+    }
+
     /**
      * @param \PDepend\Source\Tokenizer\Tokenizer $tokenizer
      * @param \PDepend\Source\Builder\Builder $builder

src/test/resources/files/Source/Language/PHP/PHPParserVersion80/testNullableTypedProperties.php

@@ -0,0 +1,4 @@
+<?php
+class User {
+    public null|int|float $number;
+}