From b00da37189c6102668e8adc70366278956103fca Mon Sep 17 00:00:00 2001
From: Dunqing <29533304+Dunqing@users.noreply.github.com>
Date: Wed, 24 Dec 2025 01:05:05 +0000
Subject: [PATCH] feat(formatter): normalize line break for directive (#17303)

Fixes panic caused by
https://github.com/oxc-project/oxc/blob/88a38b249a4d5927c733c2ef029a9ebc3fc13c48/crates/oxc_formatter/src/formatter/builders.rs#L336-L348

in #17261
---
 .../src/formatter/format_element/mod.rs       |  1 -
 crates/oxc_formatter/src/utils/string.rs      | 27 +++++++++++++++----
 2 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/crates/oxc_formatter/src/formatter/format_element/mod.rs b/crates/oxc_formatter/src/formatter/format_element/mod.rs
index 74d39e0667f6c..a6479d42e2c79 100644
--- a/crates/oxc_formatter/src/formatter/format_element/mod.rs
+++ b/crates/oxc_formatter/src/formatter/format_element/mod.rs
@@ -201,7 +201,6 @@ pub const LINE_TERMINATORS: [char; 3] = ['\r', LINE_SEPARATOR, PARAGRAPH_SEPARAT
 
 /// Replace the line terminators matching the provided list with "\n"
 /// since its the only line break type supported by the printer
-#[expect(unused)]
 pub fn normalize_newlines<const N: usize>(text: &str, terminators: [char; N]) -> Cow<'_, str> {
     let mut result = String::new();
     let mut last_end = 0;
diff --git a/crates/oxc_formatter/src/utils/string.rs b/crates/oxc_formatter/src/utils/string.rs
index 7d6e466902c03..4f5bdae58250e 100644
--- a/crates/oxc_formatter/src/utils/string.rs
+++ b/crates/oxc_formatter/src/utils/string.rs
@@ -208,7 +208,7 @@ impl<'a> LiteralStringNormalizer<'a> {
     }
 
     fn normalize_directive(&self, string_information: StringInformation) -> Cow<'a, str> {
-        // In diretcives, unnecessary escapes should be preserved.
+        // In directives, unnecessary escapes should be preserved.
         // See https://github.com/prettier/prettier/issues/1555
         // Thus we don't normalize the string.
         //
@@ -217,10 +217,27 @@ impl<'a> LiteralStringNormalizer<'a> {
         //
         // Note that we could change the quotes if the preferred quote is escaped.
         // However, Prettier doesn't go that far.
-        if string_information.raw_content_has_quotes {
-            Cow::Borrowed(self.token.string)
-        } else {
-            self.swap_quotes(self.raw_content(), string_information)
+        let normalized = normalize_newlines(self.raw_content(), ['\r']);
+        match normalized {
+            Cow::Borrowed(string) => {
+                if string_information.raw_content_has_quotes {
+                    Cow::Borrowed(self.token.string)
+                } else {
+                    self.swap_quotes(string, string_information)
+                }
+            }
+            Cow::Owned(string) => {
+                let mut s = String::with_capacity(string.len() + 2);
+                let quote = if string_information.raw_content_has_quotes {
+                    string_information.current_quote.as_char()
+                } else {
+                    string_information.preferred_quote.as_char()
+                };
+                s.push(quote);
+                s.push_str(&string);
+                s.push(quote);
+                Cow::Owned(s)
+            }
         }
     }