Merge #6534

6534: Fix attachment of inner doc comments r=matklad a=matklad

bors r+
🤖

Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>

crates/syntax/src/ast.rs

@@ -115,7 +115,22 @@ fn test_doc_comment_none() {
 }
 
 #[test]
-fn test_doc_comment_of_items() {
+fn test_outer_doc_comment_of_items() {
+    let file = SourceFile::parse(
+        r#"
+        /// doc
+        // non-doc
+        mod foo {}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let module = file.syntax().descendants().find_map(Module::cast).unwrap();
+    assert_eq!("doc", module.doc_comment_text().unwrap());
+}
+
+#[test]
+fn test_inner_doc_comment_of_items() {
     let file = SourceFile::parse(
         r#"
         //! doc
@@ -126,7 +141,7 @@ fn test_doc_comment_of_items() {
     .ok()
     .unwrap();
     let module = file.syntax().descendants().find_map(Module::cast).unwrap();
-    assert_eq!("doc", module.doc_comment_text().unwrap());
+    assert!(module.doc_comment_text().is_none());
 }
 
 #[test]

crates/syntax/src/ast/token_ext.rs

@@ -14,16 +14,15 @@ use crate::{
 
 impl ast::Comment {
     pub fn kind(&self) -> CommentKind {
-        kind_by_prefix(self.text())
+        CommentKind::from_text(self.text())
     }
 
     pub fn prefix(&self) -> &'static str {
-        for (prefix, k) in COMMENT_PREFIX_TO_KIND.iter() {
-            if *k == self.kind() && self.text().starts_with(prefix) {
-                return prefix;
-            }
-        }
-        unreachable!()
+        let &(prefix, _kind) = CommentKind::BY_PREFIX
+            .iter()
+            .find(|&(prefix, kind)| self.kind() == *kind && self.text().starts_with(prefix))
+            .unwrap();
+        prefix
     }
 }
 
@@ -55,29 +54,25 @@ pub enum CommentPlacement {
     Outer,
 }
 
-const COMMENT_PREFIX_TO_KIND: &[(&str, CommentKind)] = {
-    use {CommentPlacement::*, CommentShape::*};
-    &[
-        ("////", CommentKind { shape: Line, doc: None }),
-        ("///", CommentKind { shape: Line, doc: Some(Outer) }),
-        ("//!", CommentKind { shape: Line, doc: Some(Inner) }),
-        ("/**", CommentKind { shape: Block, doc: Some(Outer) }),
-        ("/*!", CommentKind { shape: Block, doc: Some(Inner) }),
-        ("//", CommentKind { shape: Line, doc: None }),
-        ("/*", CommentKind { shape: Block, doc: None }),
-    ]
-};
+impl CommentKind {
+    const BY_PREFIX: [(&'static str, CommentKind); 8] = [
+        ("/**/", CommentKind { shape: CommentShape::Block, doc: None }),
+        ("////", CommentKind { shape: CommentShape::Line, doc: None }),
+        ("///", CommentKind { shape: CommentShape::Line, doc: Some(CommentPlacement::Outer) }),
+        ("//!", CommentKind { shape: CommentShape::Line, doc: Some(CommentPlacement::Inner) }),
+        ("/**", CommentKind { shape: CommentShape::Block, doc: Some(CommentPlacement::Outer) }),
+        ("/*!", CommentKind { shape: CommentShape::Block, doc: Some(CommentPlacement::Inner) }),
+        ("//", CommentKind { shape: CommentShape::Line, doc: None }),
+        ("/*", CommentKind { shape: CommentShape::Block, doc: None }),
+    ];
 
-fn kind_by_prefix(text: &str) -> CommentKind {
-    if text == "/**/" {
-        return CommentKind { shape: CommentShape::Block, doc: None };
+    pub(crate) fn from_text(text: &str) -> CommentKind {
+        let &(_prefix, kind) = CommentKind::BY_PREFIX
+            .iter()
+            .find(|&(prefix, _kind)| text.starts_with(prefix))
+            .unwrap();
+        kind
     }
-    for (prefix, kind) in COMMENT_PREFIX_TO_KIND.iter() {
-        if text.starts_with(prefix) {
-            return *kind;
-        }
-    }
-    panic!("bad comment text: {:?}", text)
 }
 
 impl ast::Whitespace {

crates/syntax/src/parsing/text_tree_sink.rs

@@ -5,6 +5,7 @@ use std::mem;
 use parser::{ParseError, TreeSink};
 
 use crate::{
+    ast,
     parsing::Token,
     syntax_node::GreenNode,
     SmolStr, SyntaxError,
@@ -153,24 +154,22 @@ fn n_attached_trivias<'a>(
 
             while let Some((i, (kind, text))) = trivias.next() {
                 match kind {
-                    WHITESPACE => {
-                        if text.contains("\n\n") {
+                    WHITESPACE if text.contains("\n\n") => {
                         // we check whether the next token is a doc-comment
                         // and skip the whitespace in this case
-                            if let Some((peek_kind, peek_text)) =
-                                trivias.peek().map(|(_, pair)| pair)
-                            {
-                                if *peek_kind == COMMENT
-                                    && peek_text.starts_with("///")
-                                    && !peek_text.starts_with("////")
-                                {
+                        if let Some((COMMENT, peek_text)) = trivias.peek().map(|(_, pair)| pair) {
+                            let comment_kind = ast::CommentKind::from_text(peek_text);
+                            if comment_kind.doc == Some(ast::CommentPlacement::Outer) {
                                 continue;
                             }
                         }
                         break;
                     }
-                    }
                     COMMENT => {
+                        let comment_kind = ast::CommentKind::from_text(text);
+                        if comment_kind.doc == Some(ast::CommentPlacement::Inner) {
+                            break;
+                        }
                         res = i + 1;
                     }
                     _ => (),

crates/syntax/test_data/parser/ok/0037_mod.rast

@@ -1,9 +1,9 @@
 SOURCE_FILE@0..93
   COMMENT@0..60 "// https://github.com ..."
   WHITESPACE@60..62 "\n\n"
-  MODULE@62..93
   COMMENT@62..70 "//! docs"
   WHITESPACE@70..71 "\n"
+  MODULE@71..93
     COMMENT@71..82 "// non-docs"
     WHITESPACE@82..83 "\n"
     MOD_KW@83..86 "mod"