feature #34329 [ExpressionLanguage] add XOR operator (ottaviano)

This PR was merged into the 4.4 branch.

Discussion
----------

[ExpressionLanguage] add XOR operator

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Tickets       | ~
| License       | MIT
| Doc PR        | ~

👋
little PR for adding the best logical operator: `XOR`

Commits
-------

46fe91781d [ExpressionLanguage] add XOR operator

src/Symfony/Component/ExpressionLanguage/CHANGELOG.md

@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+4.4.0
+-----
+
+ * add `xor` operator
+
 4.0.0
 -----
 

src/Symfony/Component/ExpressionLanguage/Lexer.php

@@ -73,7 +73,7 @@ class Lexer
                 // strings
                 $tokens[] = new Token(Token::STRING_TYPE, stripcslashes(substr($match[0], 1, -1)), $cursor + 1);
                 $cursor += \strlen($match[0]);
-            } elseif (preg_match('/not in(?=[\s(])|\!\=\=|not(?=[\s(])|and(?=[\s(])|\=\=\=|\>\=|or(?=[\s(])|\<\=|\*\*|\.\.|in(?=[\s(])|&&|\|\||matches|\=\=|\!\=|\*|~|%|\/|\>|\||\!|\^|&|\+|\<|\-/A', $expression, $match, 0, $cursor)) {
+            } elseif (preg_match('/not in(?=[\s(])|\!\=\=|not(?=[\s(])|and(?=[\s(])|\=\=\=|\>\=|or(?=[\s(])|xor(?=[\s(])|\<\=|\*\*|\.\.|in(?=[\s(])|&&|\|\||matches|\=\=|\!\=|\*|~|%|\/|\>|\||\!|\^|&|\+|\<|\-/A', $expression, $match, 0, $cursor)) {
                 // operators
                 $tokens[] = new Token(Token::OPERATOR_TYPE, $match[0], $cursor + 1);
                 $cursor += \strlen($match[0]);

src/Symfony/Component/ExpressionLanguage/Node/BinaryNode.php

@@ -104,6 +104,8 @@ class BinaryNode extends Node
             case 'or':
             case '||':
                 return $left || $this->nodes['right']->evaluate($functions, $values);
+            case 'xor':
+                return $left xor $this->nodes['right']->evaluate($functions, $values);
             case 'and':
             case '&&':
                 return $left && $this->nodes['right']->evaluate($functions, $values);

src/Symfony/Component/ExpressionLanguage/Parser.php

@@ -45,6 +45,7 @@ class Parser
         $this->binaryOperators = [
             'or' => ['precedence' => 10, 'associativity' => self::OPERATOR_LEFT],
             '||' => ['precedence' => 10, 'associativity' => self::OPERATOR_LEFT],
+            'xor' => ['precedence' => 13, 'associativity' => self::OPERATOR_LEFT],
             'and' => ['precedence' => 15, 'associativity' => self::OPERATOR_LEFT],
             '&&' => ['precedence' => 15, 'associativity' => self::OPERATOR_LEFT],
             '|' => ['precedence' => 16, 'associativity' => self::OPERATOR_LEFT],

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

@@ -256,4 +256,35 @@ class ExpressionLanguageTest extends TestCase
             ],
         ];
     }
+
+    /**
+     * @dataProvider getLogicalOperators
+     */
+    public function testLogicalOperators($expression, $expected)
+    {
+        $this->assertSame($expected, (new ExpressionLanguage())->evaluate($expression));
+    }
+
+    public function getLogicalOperators()
+    {
+        return [
+            // AND
+            ['true and true', true],
+            ['true and false', false],
+            ['false and true', false],
+            ['false and false', false],
+
+            // OR
+            ['true or true', true],
+            ['true or false', true],
+            ['false or true', true],
+            ['false or false', false],
+
+            // XOR
+            ['true xor true', false],
+            ['true xor false', true],
+            ['false xor true', true],
+            ['false xor false', false],
+        ];
+    }
 }

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

@@ -114,6 +114,14 @@ class LexerTest extends TestCase
                 [new Token('string', '#foo', 1)],
                 '"#foo"',
             ],
+            [
+                [
+                    new Token('name', 'a', 1),
+                    new Token('operator', 'xor', 3),
+                    new Token('name', 'b', 7),
+                ],
+                'a xor b',
+            ],
         ];
     }
 }

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

@@ -151,6 +151,11 @@ class ParserTest extends TestCase
                 'bar',
                 ['foo' => 'bar'],
             ],
+
+            [
+                new Node\BinaryNode('xor', new Node\ConstantNode(true), new Node\ConstantNode(false)),
+                'true xor false',
+            ],
         ];
     }