From 5c476407271ecb701eee36d0bb78bc228310a3f5 Mon Sep 17 00:00:00 2001
From: Ben Thomson <git@alfreido.com>
Date: Fri, 18 Feb 2022 16:58:31 +0800
Subject: [PATCH] Retain spaceless tag in Twig

---
 modules/system/twig/Extension.php            |  4 ++-
 modules/system/twig/Loader.php               |  8 ++---
 modules/system/twig/SecurityPolicy.php       |  6 ++--
 modules/system/twig/SpacelessNode.php        | 38 ++++++++++++++++++++
 modules/system/twig/SpacelessTokenParser.php | 29 +++++++++++++++
 tests/unit/system/twig/SpacelessTest.php     | 25 +++++++++++++
 6 files changed, 102 insertions(+), 8 deletions(-)
 create mode 100644 modules/system/twig/SpacelessNode.php
 create mode 100644 modules/system/twig/SpacelessTokenParser.php
 create mode 100644 tests/unit/system/twig/SpacelessTest.php

diff --git a/modules/system/twig/Extension.php b/modules/system/twig/Extension.php
index c564854d14..372ed7903d 100644
--- a/modules/system/twig/Extension.php
+++ b/modules/system/twig/Extension.php
@@ -84,7 +84,9 @@ public function getFilters()
      */
     public function getTokenParsers()
     {
-        $parsers = [];
+        $parsers = [
+            new SpacelessTokenParser
+        ];
 
         /*
          * Include extensions provided by plugins
diff --git a/modules/system/twig/Loader.php b/modules/system/twig/Loader.php
index cf0a5accf2..e4fd2641d2 100644
--- a/modules/system/twig/Loader.php
+++ b/modules/system/twig/Loader.php
@@ -45,17 +45,17 @@ protected function findTemplate($name)
         return $this->cache[$name] = $path;
     }
 
-    public function getSourceContext($name)
+    public function getSourceContext(string $name): \Twig\Source
     {
         return new TwigSource(File::get($this->findTemplate($name)), $name);
     }
 
-    public function getCacheKey($name)
+    public function getCacheKey(string $name): string
     {
         return $this->findTemplate($name);
     }
 
-    public function isFresh($name, $time)
+    public function isFresh(string $name, int $time): bool
     {
         return File::lastModified($this->findTemplate($name)) <= $time;
     }
@@ -65,7 +65,7 @@ public function getFilename($name)
         return $this->findTemplate($name);
     }
 
-    public function exists($name)
+    public function exists(string $name)
     {
         try {
             $this->findTemplate($name);
diff --git a/modules/system/twig/SecurityPolicy.php b/modules/system/twig/SecurityPolicy.php
index b1920c586d..19d2c348e2 100644
--- a/modules/system/twig/SecurityPolicy.php
+++ b/modules/system/twig/SecurityPolicy.php
@@ -56,7 +56,7 @@ public function __construct()
      * @throws SecurityNotAllowedFilterError if a given filter is not allowed
      * @throws SecurityNotAllowedFunctionError if a given function is not allowed
      */
-    public function checkSecurity($tags, $filters, $functions)
+    public function checkSecurity($tags, $filters, $functions): void
     {
     }
 
@@ -67,7 +67,7 @@ public function checkSecurity($tags, $filters, $functions)
      * @param string $property
      * @throws SecurityNotAllowedPropertyError
      */
-    public function checkPropertyAllowed($obj, $property)
+    public function checkPropertyAllowed($obj, $property): void
     {
     }
 
@@ -78,7 +78,7 @@ public function checkPropertyAllowed($obj, $property)
      * @param string $method
      * @throws SecurityNotAllowedMethodError
      */
-    public function checkMethodAllowed($obj, $method)
+    public function checkMethodAllowed($obj, $method): void
     {
         // No need to check Twig internal objects
         if ($obj instanceof Template || $obj instanceof Markup) {
diff --git a/modules/system/twig/SpacelessNode.php b/modules/system/twig/SpacelessNode.php
new file mode 100644
index 0000000000..939326596c
--- /dev/null
+++ b/modules/system/twig/SpacelessNode.php
@@ -0,0 +1,38 @@
+<?php namespace System\Twig;
+
+use Twig\Compiler;
+use Twig\Node\Node;
+use Twig\Node\NodeOutputInterface;
+
+/**
+ * Represents a spaceless node.
+ *
+ * It removes spaces between HTML tags.
+ *
+ * Removed in Twig 3.0, but retained in Winter CMS for compatibility.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class SpacelessNode extends Node implements NodeOutputInterface
+{
+    public function __construct(Node $body, int $lineno, string $tag = 'spaceless')
+    {
+        parent::__construct(['body' => $body], [], $lineno, $tag);
+    }
+
+    public function compile(Compiler $compiler)
+    {
+        $compiler
+            ->addDebugInfo($this)
+        ;
+        if ($compiler->getEnvironment()->isDebug()) {
+            $compiler->write("ob_start();\n");
+        } else {
+            $compiler->write("ob_start(function () { return ''; });\n");
+        }
+        $compiler
+            ->subcompile($this->getNode('body'))
+            ->write("echo trim(preg_replace('/>\s+</', '><', ob_get_clean()));\n")
+        ;
+    }
+}
diff --git a/modules/system/twig/SpacelessTokenParser.php b/modules/system/twig/SpacelessTokenParser.php
new file mode 100644
index 0000000000..d17eab1500
--- /dev/null
+++ b/modules/system/twig/SpacelessTokenParser.php
@@ -0,0 +1,29 @@
+<?php namespace System\Twig;
+
+use Twig\Token;
+use Twig\TokenParser\AbstractTokenParser;
+
+final class SpacelessTokenParser extends AbstractTokenParser
+{
+    public function parse(Token $token)
+    {
+        $stream = $this->parser->getStream();
+        $lineno = $token->getLine();
+
+        $stream->expect(/* Token::BLOCK_END_TYPE */ 3);
+        $body = $this->parser->subparse([$this, 'decideSpacelessEnd'], true);
+        $stream->expect(/* Token::BLOCK_END_TYPE */ 3);
+
+        return new SpacelessNode($body, $lineno, $this->getTag());
+    }
+
+    public function decideSpacelessEnd(Token $token)
+    {
+        return $token->test('endspaceless');
+    }
+
+    public function getTag()
+    {
+        return 'spaceless';
+    }
+}
diff --git a/tests/unit/system/twig/SpacelessTest.php b/tests/unit/system/twig/SpacelessTest.php
new file mode 100644
index 0000000000..7f58468415
--- /dev/null
+++ b/tests/unit/system/twig/SpacelessTest.php
@@ -0,0 +1,25 @@
+<?php
+
+class SpacelessTest extends TestCase
+{
+    public function testSpacelessNode()
+    {
+        $twig = $this->app->make('twig.environment');
+        $template = $twig->createTemplate(
+            '<p>Test</p>
+
+            {% spaceless %}
+                <p class="test-1 test-2">This is a sentence.</p>
+
+                <p> This is another sentence.</p>
+            {% endspaceless %}'
+        );
+
+        $this->assertEquals(
+            '<p>Test</p>
+
+            <p class="test-1 test-2">This is a sentence.</p><p> This is another sentence.</p>',
+            $template->render()
+        );
+    }
+}