Account for query offset in files for errors

Author: vladar

src/Error/SyntaxError.php

@@ -14,8 +14,13 @@ class SyntaxError extends Error
     public function __construct(Source $source, $position, $description)
     {
         $location = $source->getLocation($position);
+        $line = $location->line + $source->locationOffset->line - 1;
+        $columnOffset = self::getColumnOffset($source, $location);
+        $column = $location->column + $columnOffset;
+
         $syntaxError =
-            "Syntax Error {$source->name} ({$location->line}:{$location->column}) $description\n\n" .
+            "Syntax Error {$source->name} ({$line}:{$column}) $description\n" .
+            "\n".
             self::highlightSourceAtLocation($source, $location);
 
         parent::__construct($syntaxError, null, $source, [$position]);
@@ -29,22 +34,38 @@ public function __construct(Source $source, $position, $description)
     public static function highlightSourceAtLocation(Source $source, SourceLocation $location)
     {
         $line = $location->line;
-        $prevLineNum = (string) ($line - 1);
-        $lineNum = (string) $line;
-        $nextLineNum = (string) ($line + 1);
+        $lineOffset = $source->locationOffset->line - 1;
+        $columnOffset = self::getColumnOffset($source, $location);
+
+        $contextLine = $line + $lineOffset;
+        $prevLineNum = (string) ($contextLine - 1);
+        $lineNum = (string) $contextLine;
+        $nextLineNum = (string) ($contextLine + 1);
         $padLen = mb_strlen($nextLineNum, 'UTF-8');
 
         $unicodeChars = json_decode('"\u2028\u2029"'); // Quick hack to get js-compatible representation of these chars
         $lines = preg_split('/\r\n|[\n\r' . $unicodeChars . ']/su', $source->body);
 
-        $lpad = function($len, $str) {
+        $whitespace = function ($len) {
+            return str_repeat(' ', $len);
+        };
+
+        $lpad = function ($len, $str) {
             return str_pad($str, $len - mb_strlen($str, 'UTF-8') + 1, ' ', STR_PAD_LEFT);
         };
 
+        $lines[0] = $whitespace($source->locationOffset->column - 1) . $lines[0];
+
         return
             ($line >= 2 ? $lpad($padLen, $prevLineNum) . ': ' . $lines[$line - 2] . "\n" : '') .
             ($lpad($padLen, $lineNum) . ': ' . $lines[$line - 1] . "\n") .
-            (str_repeat(' ', 1 + $padLen + $location->column) . "^\n") .
+            ($whitespace(2 + $padLen + $location->column - 1 + $columnOffset) . "^\n") .
             ($line < count($lines) ? $lpad($padLen, $nextLineNum) . ': ' . $lines[$line] . "\n" : '');
     }
+
+    public static function getColumnOffset(Source $source, SourceLocation $location)
+    {
+        return $location->line === 1 ? $source->locationOffset->column - 1 : 0;
+    }
+
 }

src/Language/Source.php

@@ -3,6 +3,10 @@
 
 use GraphQL\Utils\Utils;
 
+/**
+ * Class Source
+ * @package GraphQL\Language
+ */
 class Source
 {
     /**
@@ -20,7 +24,26 @@ class Source
      */
     public $name;
 
-    public function __construct($body, $name = null)
+    /**
+     * @var SourceLocation
+     */
+    public $locationOffset;
+
+    /**
+     * Source constructor.
+     *
+     * A representation of source input to GraphQL.
+     * `name` and `locationOffset` are optional. They are useful for clients who
+     * store GraphQL documents in source files; for example, if the GraphQL input
+     * starts at line 40 in a file named Foo.graphql, it might be useful for name to
+     * be "Foo.graphql" and location to be `{ line: 40, column: 0 }`.
+     * line and column in locationOffset are 1-indexed
+     *
+     * @param $body
+     * @param null $name
+     * @param SourceLocation|null $location
+     */
+    public function __construct($body, $name = null, SourceLocation $location = null)
     {
         Utils::invariant(
             is_string($body),
@@ -30,6 +53,16 @@ public function __construct($body, $name = null)
         $this->body = $body;
         $this->length = mb_strlen($body, 'UTF-8');
         $this->name = $name ?: 'GraphQL';
+        $this->locationOffset = $location ?: new SourceLocation(1, 1);
+
+        Utils::invariant(
+            $this->locationOffset->line > 0,
+            'line in locationOffset is 1-indexed and must be positive'
+        );
+        Utils::invariant(
+            $this->locationOffset->column > 0,
+            'column in locationOffset is 1-indexed and must be positive'
+        );
     }
 
     /**

tests/Language/LexerTest.php

@@ -3,6 +3,7 @@
 
 use GraphQL\Language\Lexer;
 use GraphQL\Language\Source;
+use GraphQL\Language\SourceLocation;
 use GraphQL\Language\Token;
 use GraphQL\Error\SyntaxError;
 use GraphQL\Utils\Utils;
@@ -107,14 +108,14 @@ public function testSkipsWhitespacesAndComments()
      */
     public function testErrorsRespectWhitespace()
     {
-        $example = "
+        $str = '' .
+            "\n" .
+            "\n" .
+            "    ?\n" .
+            "\n";
 
-    ?
-
-
-";
         try {
-            $this->lexOne($example);
+            $this->lexOne($str);
             $this->fail('Expected exception not thrown');
         } catch (SyntaxError $e) {
             $this->assertEquals(
@@ -129,6 +130,48 @@ public function testErrorsRespectWhitespace()
        }
     }
 
+    /**
+     * @it updates line numbers in error for file context
+     */
+    public function testUpdatesLineNumbersInErrorForFileContext()
+    {
+        $str = '' .
+            "\n" .
+            "\n" .
+            "     ?\n" .
+            "\n";
+        $source = new Source($str, 'foo.js', new SourceLocation(11, 12));
+
+        $this->setExpectedException(
+            SyntaxError::class,
+            'Syntax Error foo.js (13:6) ' .
+            'Cannot parse the unexpected character "?".' . "\n" .
+            "\n" .
+            '12: ' . "\n" .
+            '13:      ?' . "\n" .
+            '         ^' . "\n" .
+            '14: ' . "\n"
+        );
+        $lexer = new Lexer($source);
+        $lexer->advance();
+    }
+
+    public function testUpdatesColumnNumbersInErrorForFileContext()
+    {
+        $source = new Source('?', 'foo.js', new SourceLocation(1, 5));
+
+        $this->setExpectedException(
+            SyntaxError::class,
+            'Syntax Error foo.js (1:5) ' .
+            'Cannot parse the unexpected character "?".' . "\n" .
+            "\n" .
+            '1:     ?' . "\n" .
+            '       ^' . "\n"
+        );
+        $lexer = new Lexer($source);
+        $lexer->advance();
+    }
+
     /**
      * @it lexes strings
      */