added the spaceship operator

CHANGELOG

@@ -1,5 +1,6 @@
 * 2.12.0 (2019-XX-XX)
 
+ * added the spaceship operator ("<=>"), useful when using an arrow function in the "sort" filter
  * added support for an "arrow" function on the "sort" filter
  * added the CssInliner extension in the "extra" repositories: "inline_css"
    filter

doc/filters/sort.rst

@@ -28,15 +28,18 @@ You can pass an arrow function to sort the array:
         { name: 'Grapes', quantity: 4 },
     ] %}
 
-    {% for fruit in fruits|sort((a, b) => a.quantity == b.quantity ? 0 : (a.quantity > b.quantity ? 1 : -1))|column('name') %}
+    {% for fruit in fruits|sort((a, b) => a.quantity <=> b.quantity)|column('name') %}
         {{ fruit }}
     {% endfor %}
 
     {# output in this order: Oranges, Grapes, Apples #}
 
+Note the usage of the `spaceship`_ operator to simplify the comparison.
+
 Arguments
 ---------
 
 * ``arrow``: An arrow function
 
 .. _`asort`: https://secure.php.net/asort
+.. _`spaceship`: https://www.php.net/manual/en/language.operators.comparison.php

doc/templates.rst

@@ -509,9 +509,9 @@ Twig allows expressions everywhere.
 
     The operator precedence is as follows, with the lowest-precedence operators
     listed first: ``?:`` (ternary operator), ``b-and``, ``b-xor``, ``b-or``,
-    ``or``, ``and``, ``==``, ``!=``, ``<``, ``>``, ``>=``, ``<=``, ``in``,
-    ``matches``, ``starts with``, ``ends with``, ``..``, ``+``, ``-``, ``~``,
-    ``*``, ``/``, ``//``, ``%``, ``is`` (tests), ``**``, ``??``, ``|``
+    ``or``, ``and``, ``==``, ``!=``, ``<=>``, ``<``, ``>``, ``>=``, ``<=``,
+    ``in``, ``matches``, ``starts with``, ``ends with``, ``..``, ``+``, ``-``,
+    ``~``, ``*``, ``/``, ``//``, ``%``, ``is`` (tests), ``**``, ``??``, ``|``
     (filters), ``[]``, and ``.``:
 
     .. code-block:: twig

src/Extension/CoreExtension.php

@@ -34,6 +34,7 @@ use Twig\Node\Expression\Binary\NotInBinary;
 use Twig\Node\Expression\Binary\OrBinary;
 use Twig\Node\Expression\Binary\PowerBinary;
 use Twig\Node\Expression\Binary\RangeBinary;
+use Twig\Node\Expression\Binary\SpaceshipBinary;
 use Twig\Node\Expression\Binary\StartsWithBinary;
 use Twig\Node\Expression\Binary\SubBinary;
 use Twig\Node\Expression\Filter\DefaultFilter;
@@ -309,6 +310,7 @@ final class CoreExtension extends AbstractExtension
                 'b-and' => ['precedence' => 18, 'class' => BitwiseAndBinary::class, 'associativity' => ExpressionParser::OPERATOR_LEFT],
                 '==' => ['precedence' => 20, 'class' => EqualBinary::class, 'associativity' => ExpressionParser::OPERATOR_LEFT],
                 '!=' => ['precedence' => 20, 'class' => NotEqualBinary::class, 'associativity' => ExpressionParser::OPERATOR_LEFT],
+                '<=>' => ['precedence' => 20, 'class' => SpaceshipBinary::class, 'associativity' => ExpressionParser::OPERATOR_LEFT],
                 '<' => ['precedence' => 20, 'class' => LessBinary::class, 'associativity' => ExpressionParser::OPERATOR_LEFT],
                 '>' => ['precedence' => 20, 'class' => GreaterBinary::class, 'associativity' => ExpressionParser::OPERATOR_LEFT],
                 '>=' => ['precedence' => 20, 'class' => GreaterEqualBinary::class, 'associativity' => ExpressionParser::OPERATOR_LEFT],

src/Node/Expression/Binary/SpaceshipBinary.php

@@ -0,0 +1,22 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Twig\Node\Expression\Binary;
+
+use Twig\Compiler;
+
+class SpaceshipBinary extends AbstractBinary
+{
+    public function operator(Compiler $compiler)
+    {
+        return $compiler->raw('<=>');
+    }
+}

tests/Fixtures/filters/sort_with_arrow.test

@@ -2,6 +2,7 @@
 "sort" filter
 --TEMPLATE--
 {{ fruits|sort((a, b) => a.quantity == b.quantity ? 0 : (a.quantity > b.quantity ? 1 : -1))|column('name')|join(', ') }}
+{{ fruits|sort((a, b) => a.quantity <=> b.quantity)|column('name')|join(', ') }}
 --DATA--
 return [
     'fruits' => [
@@ -12,3 +13,4 @@ return [
 ]
 --EXPECT--
 Oranges, Grapes, Apples
+Oranges, Grapes, Apples