Fix NULL handling when binding boolean parameter for native pgsql driver

src/Driver/PgSQL/Statement.php

@@ -82,7 +82,12 @@
         }
 
         if ($type === ParameterType::BOOLEAN) {
-            $this->parameters[$this->parameterMap[$param]]     = (bool) $value === false ? 'f' : 't';
+            $booleanValue = null;
+            if ($value !== null) {
+                $booleanValue = (bool) $value === false ? 'f' : 't';
+            }
+
+            $this->parameters[$this->parameterMap[$param]]     = $booleanValue;
             $this->parameterTypes[$this->parameterMap[$param]] = ParameterType::STRING;
         } else {
             $this->parameters[$this->parameterMap[$param]]     = $value;

tests/Functional/BooleanBindingTest.php

@@ -9,6 +9,9 @@
 use Doctrine\DBAL\Tests\FunctionalTestCase;
 use Doctrine\DBAL\Tests\TestUtil;
 
+use function assert;
+use function is_bool;
+
 class BooleanBindingTest extends FunctionalTestCase
 {
     protected function setUp(): void
@@ -18,7 +21,7 @@ protected function setUp(): void
         }
 
         $table = new Table('boolean_test_table');
-        $table->addColumn('val', 'boolean');
+        $table->addColumn('val', 'boolean', ['notnull' => false]);
         $this->dropAndCreateTable($table);
     }
 
@@ -28,7 +31,7 @@ protected function tearDown(): void
     }
 
     /** @dataProvider booleanProvider */
-    public function testBooleanInsert(bool $input): void
+    public function testBooleanInsert(?bool $input): void
     {
         $queryBuilder = $this->connection->createQueryBuilder();
 
@@ -37,11 +40,23 @@ public function testBooleanInsert(bool $input): void
         ])->executeStatement();
 
         self::assertSame(1, $result);
+
+        $valueFromDatabase = $this->connection->createQueryBuilder()
+            ->select('val')->from('boolean_test_table')
+            ->executeQuery()->fetchOne();
+
+        assert($valueFromDatabase === null || is_bool($valueFromDatabase));
+
+        self::assertSame(
+            $input,
+            $this->connection->convertToPHPValue($valueFromDatabase, 'boolean'),
+            'Must return from database the same value inserted.',
+        );
     }
 
-    /** @return bool[][] */
+    /** @return array<int, list<bool|null>> */
     public static function booleanProvider(): array
     {
-        return [[true], [false]];
+        return [[true], [false], [null]];
     }
 }