Fix QueryString php variable extraction #146

Author: nyamsprod

interfaces/QueryString.php

@@ -249,23 +249,27 @@ private static function extractPhpVariable(array $data, array|string $name, stri
         }
 
         $key = substr($name, 0, $leftBracketPosition);
+        if ('' === $key) {
+            $key = '0';
+        }
+
         if (!array_key_exists($key, $data) || !is_array($data[$key])) {
             $data[$key] = [];
         }
 
-        $index = substr($name, $leftBracketPosition + 1, $rightBracketPosition - $leftBracketPosition - 1);
-        if ('' === $index) {
+        $remaining = substr($name, $rightBracketPosition + 1);
+        if (!str_starts_with($remaining, '[') || !str_contains($remaining, ']')) {
+            $remaining = '';
+        }
+
+        $name = substr($name, $leftBracketPosition + 1, $rightBracketPosition - $leftBracketPosition - 1).$remaining;
+        if ('' === $name) {
             $data[$key][] = $value;
 
             return $data;
         }
 
-        $remaining = substr($name, $rightBracketPosition + 1);
-        if (!str_starts_with($remaining, '[') || false === strpos($remaining, ']', 1)) {
-            $remaining = '';
-        }
-
-        $data[$key] = self::extractPhpVariable($data[$key], $index.$remaining, $value);
+        $data[$key] = self::extractPhpVariable($data[$key], $name, $value);
 
         return $data;
     }

interfaces/QueryStringTest.php

@@ -15,6 +15,7 @@
 use League\Uri\Components\Fragment;
 use League\Uri\Exceptions\SyntaxError;
 use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\Attributes\Test;
 use PHPUnit\Framework\TestCase;
 use Stringable;
 
@@ -477,4 +478,43 @@ public static function queryProvider(): array
             'Encoded unreserved chars are not decoded' => ['q=v%61lue', 'q=value'],
         ];
     }
+
+    #[Test]
+    #[DataProvider('queryWithInnerEmptyBracetsProvider')]
+    public function it_should_parse_empty_bracets_issue_146(string $query, string $expected): void
+    {
+        $data = QueryString::extract($query);
+        parse_str($query, $result);
+
+        self::assertSame($data, $result);
+        self::assertSame($expected, http_build_query($data, '', '&', PHP_QUERY_RFC3986));
+    }
+
+    public static function queryWithInnerEmptyBracetsProvider(): iterable
+    {
+        yield 'query with on level empty bracets' => [
+            'query' => 'foo[]=bar',
+            'expected' => 'foo%5B0%5D=bar',
+        ];
+
+        yield 'query with two level bracets' => [
+            'query' => 'key[][][foo][9]=bar',
+            'expected' => 'key%5B0%5D%5B0%5D%5Bfoo%5D%5B9%5D=bar',
+        ];
+
+        yield 'query with invalid remaining; close bracet without an opening bracet' => [
+            'query' => 'key[][]foo][9]=bar',
+            'expected' => 'key%5B0%5D%5B0%5D=bar',
+        ];
+
+        yield 'query with invalid remaining; no opening bracet' => [
+            'query' => 'key[]9=bar',
+            'expected' => 'key%5B0%5D=bar',
+        ];
+
+        yield 'query with invalid remaining; opening bracet no at the start of the remaining string' => [
+            'query' => 'key[]9[]=bar',
+            'expected' => 'key%5B0%5D=bar',
+        ];
+    }
 }