fix: Include frontmatter in -Zunpretty output

In the implementation (#140035), this was left as an open question for
the tracking issue (#136889).  My assumption is that this should be
carried over.

Thankfully, either way, `-Zunpretty` is unstable and we can always
change it even if we stabilize frontmatter.

1 files changed, 9 insertions, 1 deletions

diff --git a/compiler/rustc_ast_pretty/src/pprust/state.rs b/compiler/rustc_ast_pretty/src/pprust/state.rs
index 9d656253f72..def0cb74d29 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state.rs
@@ -120,7 +120,7 @@ fn gather_comments(sm: &SourceMap, path: FileName, src: String) -> Vec<Comment>
         pos += shebang_len;
     }
 
-    for token in rustc_lexer::tokenize(&text[pos..], rustc_lexer::FrontmatterAllowed::No) {
+    for token in rustc_lexer::tokenize(&text[pos..], rustc_lexer::FrontmatterAllowed::Yes) {
         let token_text = &text[pos..pos + token.len as usize];
         match token.kind {
             rustc_lexer::TokenKind::Whitespace => {
@@ -171,6 +171,14 @@ fn gather_comments(sm: &SourceMap, path: FileName, src: String) -> Vec<Comment>
                     })
                 }
             }
+            rustc_lexer::TokenKind::Frontmatter { .. } => {
+                code_to_the_left = false;
+                comments.push(Comment {
+                    style: CommentStyle::Isolated,
+                    lines: vec![token_text.to_string()],
+                    pos: start_bpos + BytePos(pos as u32),
+                });
+            }
             _ => {
                 code_to_the_left = true;
             }