From 782c7e7d1b8dfc00e44e645fed427ee6667a9551 Mon Sep 17 00:00:00 2001
From: Olli Vesslin <olli.vesslin@yle.fi>
Date: Thu, 25 Aug 2022 09:48:11 +0300
Subject: [PATCH] #226: Escape setext heading underlines.

---
 src/Converter/ParagraphConverter.php | 1 +
 tests/HtmlConverterTest.php          | 1 +
 2 files changed, 2 insertions(+)

diff --git a/src/Converter/ParagraphConverter.php b/src/Converter/ParagraphConverter.php
index 65b37a4..4246d16 100644
--- a/src/Converter/ParagraphConverter.php
+++ b/src/Converter/ParagraphConverter.php
@@ -56,6 +56,7 @@ private function escapeFirstCharacters(string $line): string
             '~~~',
             '---',
             '- - -',
+            '=',
         ];
 
         foreach ($escapable as $i) {
diff --git a/tests/HtmlConverterTest.php b/tests/HtmlConverterTest.php
index 64b9086..ed1e326 100644
--- a/tests/HtmlConverterTest.php
+++ b/tests/HtmlConverterTest.php
@@ -401,6 +401,7 @@ public function testSanitization(): void
         $this->assertHtmlGivesMarkdown($html, $markdown);
         $this->assertHtmlGivesMarkdown('<p>&gt; &gt; Look at me! &lt; &lt;</p>', '&gt; &gt; Look at me! &lt; &lt;');
         $this->assertHtmlGivesMarkdown('<p>&gt; &gt; <b>Look</b> at me! &lt; &lt;<br />&gt; Just look at me!</p>', "&gt; &gt; **Look** at me! &lt; &lt;  \n&gt; Just look at me!");
+        $this->assertHtmlGivesMarkdown('<p>Foo<br>=<br>Bar</p>', "Foo  \n\\=  \nBar");
         $this->assertHtmlGivesMarkdown('<p>Foo<br>--<br>Bar<br>Foo--</p>', "Foo  \n\\--  \nBar  \nFoo--");
         $this->assertHtmlGivesMarkdown('<ul><li>Foo<br>- Bar</li></ul>', "- Foo  \n    \\- Bar");
         $this->assertHtmlGivesMarkdown('Foo<br />* Bar', "Foo  \n\\* Bar");