Fix escaped character in links (#19849)

Co-authored-by: fisker <lionkay@gmail.com>

changelog_unreleased/markdown/19849.md

@@ -0,0 +1,16 @@
+#### Fix escaped character in links (#19849 by @Kjubikstronk)
+
+<!-- prettier-ignore -->
+```markdown
+<!-- Input -->
+[test](/hello?foo&quot\;bar)
+
+<!-- Prettier stable (First format)  -->
+[test](/hello?foo&quot;bar)
+
+<!-- Prettier stable (Second format) -->
+[test](/hello?foo"bar)
+
+<!-- Prettier main -->
+[test](/hello?foo\&quot;bar)
+```

src/language-markdown/print/mdast.js

@@ -478,6 +478,11 @@ function shouldRemainTheSameContent(path) {
   );
 }
 
+// https://spec.commonmark.org/0.31.2/#entity-and-numeric-character-references
+const characterReferenceRegex = /&(?=(?:#x[\da-f]+|#\d+|[\da-z]+);)/gi;
+const escapeCharacterReferences = (value) =>
+  value.replaceAll(characterReferenceRegex, String.raw`\&`);
+
 /**
  * @param {string} url
  * @param {boolean} unwrapBalancedParens
@@ -487,6 +492,7 @@ function printUrl(url, unwrapBalancedParens) {
   // Backslash followed by ASCII punctuation would be misinterpreted as an
   // escape sequence, so must itself be escaped.
   url = url.replaceAll(/\\(?![^!"#$%&'()*+,\-./:;<=>?@[\\\]^_`{|}~])/g, "\\\\");
+  url = escapeCharacterReferences(url);
 
   // CommonMark forbids ASCII controls, space, unbalanced parentheses, and
   // initial <, unless wrapped in <> with any inner < or > escaped. CommonMark
@@ -526,11 +532,13 @@ function printTitle(title, options, printSpace = true) {
     !title.includes(")")
   ) {
     title = title.replaceAll("\\", "\\\\");
+    title = escapeCharacterReferences(title);
     return `(${title})`; // avoid escaped quotes
   }
   const quote = getPreferredQuote(title, options.singleQuote);
   title = title.replaceAll("\\", "\\\\");
   title = title.replaceAll(quote, `\\${quote}`);
+  title = escapeCharacterReferences(title);
   return `${quote}${title}${quote}`;
 }
 

tests/format/markdown/link/__snapshots__/format.test.js.snap

@@ -141,9 +141,65 @@ proseWrap: "always"
 =====================================input======================================
 [Test](http://localhost:8080/test?language=DE&currency=EUR)
 
+[Test](/a?x&quot\\;b)
+
+[Test](/a?x&#34\\;b)
+
+[Test](/a?x&#x22\\;b)
+
+![Test](/a?x&quot\\;b)
+
+[Test](/a "x&quot\\;b")
+
+[Test](</a b?x&quot\\;c>)
+
+[Test]: /a?x&quot\\;b
+
+[Test](/a?x\\&amp;b)
+
+[Test](/a?x\\&amp;quot;b)
+
+[Test](/a "x\\&amp;b")
+
+[Test](/a "x\\&amp;quot;b")
+
+[Test](/a?x&amp;b)
+
+[Test](/a?x&amp;quot;b)
+
+[Test](/a "/a?x&amp;quot;b")
+
 =====================================output=====================================
 [Test](http://localhost:8080/test?language=DE&currency=EUR)
 
+[Test](/a?x\\&quot;b)
+
+[Test](/a?x\\&#34;b)
+
+[Test](/a?x\\&#x22;b)
+
+![Test](/a?x\\&quot;b)
+
+[Test](/a "x\\&quot;b")
+
+[Test](</a b?x\\&quot;c>)
+
+[Test]: /a?x\\&quot;b
+
+[Test](/a?x\\&amp;b)
+
+[Test](/a?x\\&amp;quot;b)
+
+[Test](/a "x\\&amp;b")
+
+[Test](/a "x\\&amp;quot;b")
+
+[Test](/a?x&b)
+
+[Test](/a?x\\&quot;b)
+
+[Test](/a "/a?x\\&quot;b")
+
 ================================================================================
 `;
 

tests/format/markdown/link/entity.md

@@ -1 +1,29 @@
 [Test](http://localhost:8080/test?language=DE&currency=EUR)
+
+[Test](/a?x&quot\;b)
+
+[Test](/a?x&#34\;b)
+
+[Test](/a?x&#x22\;b)
+
+![Test](/a?x&quot\;b)
+
+[Test](/a "x&quot\;b")
+
+[Test](</a b?x&quot\;c>)
+
+[Test]: /a?x&quot\;b
+
+[Test](/a?x\&amp;b)
+
+[Test](/a?x\&amp;quot;b)
+
+[Test](/a "x\&amp;b")
+
+[Test](/a "x\&amp;quot;b")
+
+[Test](/a?x&amp;b)
+
+[Test](/a?x&amp;quot;b)
+
+[Test](/a "/a?x&amp;quot;b")