Adjust lexer position

src/Tokens/Lexer.php

@@ -32,7 +32,7 @@ final class Lexer implements IteratorAggregate
      *
      * @var int
      */
-    private int $position = 1;
+    private int $position = 0;
 
     /**
      * Instantiate the class.

tests/Feature/ErrorsHandlingTest.php

@@ -16,9 +16,9 @@ it('lets the user handle syntax errors', function () {
     JsonParser::parse('{a}')
         ->onSyntaxError(function (SyntaxException $e) {
             expect($e)
-                ->getMessage()->toBe("Syntax error: unexpected 'a' at position 2")
+                ->getMessage()->toBe("Syntax error: unexpected 'a' at position 1")
                 ->value->toBe('a')
-                ->position->toBe(2);
+                ->position->toBe(1);
         })
         ->traverse();
 });

tests/fixtures/errors/syntax.php

@@ -4,51 +4,51 @@ return [
     [
         'json' => 'a[1, "", 3.14, [], {}]',
         'unexpected' => 'a',
-        'position' => 1,
+        'position' => 0,
     ],
     [
         'json' => '[b1, "", 3.14, [], {}]',
         'unexpected' => 'b',
-        'position' => 2,
+        'position' => 1,
     ],
     [
         'json' => '[1,c "", 3.14, [], {}]',
         'unexpected' => 'c',
-        'position' => 4,
+        'position' => 3,
     ],
     [
         'json' => '[1, d"", 3.14, [], {}]',
         'unexpected' => 'd',
-        'position' => 5,
+        'position' => 4,
     ],
     [
         'json' => '[1, "", e3.14, [], {}]',
         'unexpected' => 'e',
-        'position' => 9,
+        'position' => 8,
     ],
     [
         'json' => '[1, "", 3.14, []f, {}]',
         'unexpected' => 'f',
-        'position' => 18,
+        'position' => 17,
     ],
     [
         'json' => '[1, "", 3.14, [], g{}]',
         'unexpected' => 'g',
-        'position' => 19,
+        'position' => 18,
     ],
     [
         'json' => '[1, "", 3.14, [], {h}]',
         'unexpected' => 'h',
-        'position' => 20,
+        'position' => 19,
     ],
     [
         'json' => '[1, "", 3.14, [], {}i]',
         'unexpected' => 'i',
-        'position' => 21,
+        'position' => 20,
     ],
     [
         'json' => '[1, "", 3.14, [], {}]j',
         'unexpected' => 'j',
-        'position' => 22,
+        'position' => 21,
     ],
 ];