From a5011996fb7d418961f14c0080c9d912c8e71ef9 Mon Sep 17 00:00:00 2001
From: Marshall Bowers <elliott.codes@gmail.com>
Date: Wed, 29 May 2024 18:57:20 -0400
Subject: [PATCH] rustdoc_to_markdown: Recognize Rust code blocks (#12458)

This PR makes it so Rust code blocks are recognized and
syntax-highlighted when converting from rustdoc to Markdown.

Release Notes:

- N/A
---
 .../rustdoc_to_markdown/src/markdown_writer.rs | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/crates/rustdoc_to_markdown/src/markdown_writer.rs b/crates/rustdoc_to_markdown/src/markdown_writer.rs
index 0191ed8549..cf71982ecb 100644
--- a/crates/rustdoc_to_markdown/src/markdown_writer.rs
+++ b/crates/rustdoc_to_markdown/src/markdown_writer.rs
@@ -137,7 +137,23 @@ impl MarkdownWriter {
                     self.push_str("`")
                 }
             }
-            "pre" => self.push_str("\n```\n"),
+            "pre" => {
+                let attrs = tag.attrs.borrow();
+                let classes = attrs
+                    .iter()
+                    .find(|attr| attr.name.local.to_string() == "class")
+                    .map(|attr| {
+                        attr.value
+                            .split(' ')
+                            .map(|class| class.trim())
+                            .collect::<Vec<_>>()
+                    })
+                    .unwrap_or_default();
+                let is_rust = classes.into_iter().any(|class| class == "rust");
+                let language = if is_rust { "rs" } else { "" };
+
+                self.push_str(&format!("\n```{language}\n"))
+            }
             "ul" | "ol" => self.push_newline(),
             "li" => self.push_str("- "),
             "summary" => {