bug #22229 [ExpressionLanguage] Provide the expression in syntax errors (k0pernikus, stof)

This PR was merged into the 2.7 branch.

Discussion
----------

[ExpressionLanguage] Provide the expression in syntax errors

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #19445
| License       | MIT
| Doc PR        | n/a

This finishes the PR #19449.

Commits
-------

7cd744133d Complete the injection of the expression in all syntax errors
dc55db2a9d add expression text to SyntaxError

src/Symfony/Component/ExpressionLanguage/Lexer.php

@@ -59,12 +59,12 @@ class Lexer
             } elseif (false !== strpos(')]}', $expression[$cursor])) {
                 // closing bracket
                 if (empty($brackets)) {
-                    throw new SyntaxError(sprintf('Unexpected "%s"', $expression[$cursor]), $cursor);
+                    throw new SyntaxError(sprintf('Unexpected "%s"', $expression[$cursor]), $cursor, $expression);
                 }
 
                 list($expect, $cur) = array_pop($brackets);
                 if ($expression[$cursor] != strtr($expect, '([{', ')]}')) {
-                    throw new SyntaxError(sprintf('Unclosed "%s"', $expect), $cur);
+                    throw new SyntaxError(sprintf('Unclosed "%s"', $expect), $cur, $expression);
                 }
 
                 $tokens[] = new Token(Token::PUNCTUATION_TYPE, $expression[$cursor], $cursor + 1);
@@ -87,7 +87,7 @@ class Lexer
                 $cursor += strlen($match[0]);
             } else {
                 // unlexable
-                throw new SyntaxError(sprintf('Unexpected character "%s"', $expression[$cursor]), $cursor);
+                throw new SyntaxError(sprintf('Unexpected character "%s"', $expression[$cursor]), $cursor, $expression);
             }
         }
 
@@ -95,9 +95,9 @@ class Lexer
 
         if (!empty($brackets)) {
             list($expect, $cur) = array_pop($brackets);
-            throw new SyntaxError(sprintf('Unclosed "%s"', $expect), $cur);
+            throw new SyntaxError(sprintf('Unclosed "%s"', $expect), $cur, $expression);
         }
 
-        return new TokenStream($tokens);
+        return new TokenStream($tokens, $expression);
     }
 }

src/Symfony/Component/ExpressionLanguage/Parser.php

@@ -99,7 +99,7 @@ class Parser
 
         $node = $this->parseExpression();
         if (!$stream->isEOF()) {
-            throw new SyntaxError(sprintf('Unexpected token "%s" of value "%s"', $stream->current->type, $stream->current->value), $stream->current->cursor);
+            throw new SyntaxError(sprintf('Unexpected token "%s" of value "%s"', $stream->current->type, $stream->current->value), $stream->current->cursor, $stream->getExpression());
         }
 
         return $node;
@@ -195,13 +195,13 @@ class Parser
                     default:
                         if ('(' === $this->stream->current->value) {
                             if (false === isset($this->functions[$token->value])) {
-                                throw new SyntaxError(sprintf('The function "%s" does not exist', $token->value), $token->cursor);
+                                throw new SyntaxError(sprintf('The function "%s" does not exist', $token->value), $token->cursor, $this->stream->getExpression());
                             }
 
                             $node = new Node\FunctionNode($token->value, $this->parseArguments());
                         } else {
                             if (!in_array($token->value, $this->names, true)) {
-                                throw new SyntaxError(sprintf('Variable "%s" is not valid', $token->value), $token->cursor);
+                                throw new SyntaxError(sprintf('Variable "%s" is not valid', $token->value), $token->cursor, $this->stream->getExpression());
                             }
 
                             // is the name used in the compiled code different
@@ -227,7 +227,7 @@ class Parser
                 } elseif ($token->test(Token::PUNCTUATION_TYPE, '{')) {
                     $node = $this->parseHashExpression();
                 } else {
-                    throw new SyntaxError(sprintf('Unexpected token "%s" of value "%s"', $token->type, $token->value), $token->cursor);
+                    throw new SyntaxError(sprintf('Unexpected token "%s" of value "%s"', $token->type, $token->value), $token->cursor, $this->stream->getExpression());
                 }
         }
 
@@ -289,7 +289,7 @@ class Parser
             } else {
                 $current = $this->stream->current;
 
-                throw new SyntaxError(sprintf('A hash key must be a quoted string, a number, a name, or an expression enclosed in parentheses (unexpected token "%s" of value "%s"', $current->type, $current->value), $current->cursor);
+                throw new SyntaxError(sprintf('A hash key must be a quoted string, a number, a name, or an expression enclosed in parentheses (unexpected token "%s" of value "%s"', $current->type, $current->value), $current->cursor, $this->stream->getExpression());
             }
 
             $this->stream->expect(Token::PUNCTUATION_TYPE, ':', 'A hash key must be followed by a colon (:)');
@@ -327,7 +327,7 @@ class Parser
                     // As a result, if $token is NOT an operator OR $token->value is NOT a valid property or method name, an exception shall be thrown.
                     ($token->type !== Token::OPERATOR_TYPE || !preg_match('/[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*/A', $token->value))
                 ) {
-                    throw new SyntaxError('Expected name', $token->cursor);
+                    throw new SyntaxError('Expected name', $token->cursor, $this->stream->getExpression());
                 }
 
                 $arg = new Node\ConstantNode($token->value);
@@ -345,7 +345,7 @@ class Parser
                 $node = new Node\GetAttrNode($node, $arg, $arguments, $type);
             } elseif ('[' === $token->value) {
                 if ($node instanceof Node\GetAttrNode && Node\GetAttrNode::METHOD_CALL === $node->attributes['type'] && PHP_VERSION_ID < 50400) {
-                    throw new SyntaxError('Array calls on a method call is only supported on PHP 5.4+', $token->cursor);
+                    throw new SyntaxError('Array calls on a method call is only supported on PHP 5.4+', $token->cursor, $this->stream->getExpression());
                 }
 
                 $this->stream->next();

src/Symfony/Component/ExpressionLanguage/SyntaxError.php

@@ -13,8 +13,14 @@ namespace Symfony\Component\ExpressionLanguage;
 
 class SyntaxError extends \LogicException
 {
-    public function __construct($message, $cursor = 0)
+    public function __construct($message, $cursor = 0, $expression = '')
     {
-        parent::__construct(sprintf('%s around position %d.', $message, $cursor));
+        $message = sprintf('%s around position %d', $message, $cursor);
+        if ($expression) {
+            $message = sprintf('%s for expression `%s`', $message, $expression);
+        }
+        $message .= '.';
+
+        parent::__construct($message);
     }
 }

src/Symfony/Component/ExpressionLanguage/Tests/LexerTest.php

@@ -18,14 +18,43 @@ use Symfony\Component\ExpressionLanguage\TokenStream;
 
 class LexerTest extends TestCase
 {
+    /**
+     * @var Lexer
+     */
+    private $lexer;
+
+    protected function setUp()
+    {
+        $this->lexer = new Lexer();
+    }
+
     /**
      * @dataProvider getTokenizeData
      */
     public function testTokenize($tokens, $expression)
     {
         $tokens[] = new Token('end of expression', null, strlen($expression) + 1);
-        $lexer = new Lexer();
+        $this->assertEquals(new TokenStream($tokens, $expression), $this->lexer->tokenize($expression));
-        $this->assertEquals(new TokenStream($tokens), $lexer->tokenize($expression));
+    }
+
+    /**
+     * @expectedException \Symfony\Component\ExpressionLanguage\SyntaxError
+     * @expectedExceptionMessage Unexpected character "'" around position 33 for expression `service(faulty.expression.example').dummyMethod()`.
+     */
+    public function testTokenizeThrowsErrorWithMessage()
+    {
+        $expression = "service(faulty.expression.example').dummyMethod()";
+        $this->lexer->tokenize($expression);
+    }
+
+    /**
+     * @expectedException \Symfony\Component\ExpressionLanguage\SyntaxError
+     * @expectedExceptionMessage Unclosed "(" around position 7 for expression `service(unclosed.expression.dummyMethod()`.
+     */
+    public function testTokenizeThrowsErrorOnUnclosedBrace()
+    {
+        $expression = 'service(unclosed.expression.dummyMethod()';
+        $this->lexer->tokenize($expression);
     }
 
     public function getTokenizeData()

src/Symfony/Component/ExpressionLanguage/Tests/ParserTest.php

@@ -20,7 +20,7 @@ class ParserTest extends TestCase
 {
     /**
      * @expectedException        \Symfony\Component\ExpressionLanguage\SyntaxError
-     * @expectedExceptionMessage Variable "foo" is not valid around position 1.
+     * @expectedExceptionMessage Variable "foo" is not valid around position 1 for expression `foo`.
      */
     public function testParseWithInvalidName()
     {
@@ -31,7 +31,7 @@ class ParserTest extends TestCase
 
     /**
      * @expectedException        \Symfony\Component\ExpressionLanguage\SyntaxError
-     * @expectedExceptionMessage Variable "foo" is not valid around position 1.
+     * @expectedExceptionMessage Variable "foo" is not valid around position 1 for expression `foo`.
      */
     public function testParseWithZeroInNames()
     {

src/Symfony/Component/ExpressionLanguage/TokenStream.php

@@ -22,16 +22,19 @@ class TokenStream
 
     private $tokens;
     private $position = 0;
+    private $expression;
 
     /**
      * Constructor.
      *
-     * @param array $tokens An array of tokens
+     * @param array  $tokens     An array of tokens
+     * @param string $expression
      */
-    public function __construct(array $tokens)
+    public function __construct(array $tokens, $expression = '')
     {
         $this->tokens = $tokens;
         $this->current = $tokens[0];
+        $this->expression = $expression;
     }
 
     /**
@@ -50,7 +53,7 @@ class TokenStream
     public function next()
     {
         if (!isset($this->tokens[$this->position])) {
-            throw new SyntaxError('Unexpected end of expression', $this->current->cursor);
+            throw new SyntaxError('Unexpected end of expression', $this->current->cursor, $this->expression);
         }
 
         ++$this->position;
@@ -69,7 +72,7 @@ class TokenStream
     {
         $token = $this->current;
         if (!$token->test($type, $value)) {
-            throw new SyntaxError(sprintf('%sUnexpected token "%s" of value "%s" ("%s" expected%s)', $message ? $message.'. ' : '', $token->type, $token->value, $type, $value ? sprintf(' with value "%s"', $value) : ''), $token->cursor);
+            throw new SyntaxError(sprintf('%sUnexpected token "%s" of value "%s" ("%s" expected%s)', $message ? $message.'. ' : '', $token->type, $token->value, $type, $value ? sprintf(' with value "%s"', $value) : ''), $token->cursor, $this->expression);
         }
         $this->next();
     }
@@ -83,4 +86,14 @@ class TokenStream
     {
         return $this->current->type === Token::EOF_TYPE;
     }
+
+    /**
+     * @internal
+     *
+     * @return string
+     */
+    public function getExpression()
+    {
+        return $this->expression;
+    }
 }