[DOC-CVS] [phd] syntax/absent-php-tag: handle PHP code snippets without opening tag by pretending it exists

Author: Jordi Kroon (jordikroon)
Date: 2026-08-23T20:08:26+02:00

Commit: https://github.com/php/phd/commit/44914abe140e0ef8e6a73e04a23e3a5c6adec693
Raw diff: https://github.com/php/phd/commit/44914abe140e0ef8e6a73e04a23e3a5c6adec693.diff

handle PHP code snippets without opening tag by pretending it exists

Changed paths:
  A  tests/highlighter_php_no_open_tag.phpt
  M  phpdotnet/phd/Highlighter.php


Diff:

diff --git a/phpdotnet/phd/Highlighter.php b/phpdotnet/phd/Highlighter.php
index c59c18e7..1235a178 100644
--- a/phpdotnet/phd/Highlighter.php
+++ b/phpdotnet/phd/Highlighter.php
@@ -62,8 +62,17 @@ public function highlight($text, $role, $format)
         }
 
         if ($role == 'php') {
+            $origText = $text;
+            $prepended = false;
+            if (strpos($text, '<?') === false) {
+                $text = "<?php\n" . $text;
+                $prepended = true;
+            }
             try {
                 $highlight = highlight_string($text, true);
+                if ($prepended) {
+                    $highlight = preg_replace('/&lt;\?php(?:<br \/>|\n)/', '', $highlight, 1);
+                }
                 if (PHP_VERSION_ID >= 80300) {
                     return $highlight;
                 } else {
@@ -73,10 +82,10 @@ public function highlight($text, $role, $format)
                     ]);
                 }
             } catch (\ParseException $e) {
-                trigger_error(vsprintf("Parse error while highlighting PHP code: %s\nText: %s", [(string) $e, $text]), E_USER_WARNING);
+                trigger_error(vsprintf("Parse error while highlighting PHP code: %s\nText: %s", [(string) $e, $origText]), E_USER_WARNING);
 
                 return '<pre class="'. $role . 'code">'
-                    . htmlspecialchars($text, ENT_QUOTES, 'UTF-8')
+                    . htmlspecialchars($origText, ENT_QUOTES, 'UTF-8')
                     . "</pre>\n";
             }
         } else {
diff --git a/tests/highlighter_php_no_open_tag.phpt b/tests/highlighter_php_no_open_tag.phpt
new file mode 100644
index 00000000..4edb96b0
--- /dev/null
+++ b/tests/highlighter_php_no_open_tag.phpt
@@ -0,0 +1,19 @@
+--TEST--
+Highlighter colors PHP snippets that lack a <?php open tag
+--SKIPIF--
+<?php if (PHP_VERSION_ID < 80300) die("skip highlight_string() output differs before PHP 8.3"); ?>
+--FILE--
+<?php
+namespace phpdotnet\phd;
+
+require_once __DIR__ . "/setup.php";
+
+$highlighter = Highlighter::factory("xhtml");
+
+echo $highlighter->highlight('$kitty->eat($banana);', "php", "xhtml"), "\n";
+echo $highlighter->highlight("<?php\n\$kitty->eat(\$banana);", "php", "xhtml"), "\n";
+?>
+--EXPECT--
+<pre><code style="color: #000000"><span style="color: #0000BB">$kitty</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">eat</span><span style="color: #007700">(</span><span style="color: #0000BB">$banana</span><span style="color: #007700">);</span></code></pre>
+<pre><code style="color: #000000"><span style="color: #0000BB">&lt;?php
+$kitty</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">eat</span><span style="color: #007700">(</span><span style="color: #0000BB">$banana</span><span style="color: #007700">);</span></code></pre>