feat: optimize trailing comments of block collection

pretty_yaml/tests/fmt/comment/collection.snap

@@ -11,7 +11,7 @@ a: # a.trailingComment
 
 d:
   - 123
-# sequence
+  # sequence
 
 e:
   - 123

pretty_yaml/tests/fmt/comment/end-comment.snap

@@ -3,7 +3,7 @@ source: pretty_yaml/tests/fmt.rs
 ---
 parent:
   one: 1
-# two: 2
+  # two: 2
 
 a:
   b:

pretty_yaml/tests/fmt/comment/issue-9130.snap

@@ -4,13 +4,13 @@ source: pretty_yaml/tests/fmt.rs
 - foo: 0
   bar: 1
 
-# baz: 2
+  # baz: 2
 - quux: 3
 
 - foo: 0
   bar: 1
 
-# baz: 2
+  # baz: 2
 
-# baz: 3
+  # baz: 3
 - quux: 3

pretty_yaml/tests/fmt/comment/map-2.snap

@@ -13,7 +13,7 @@ foo1:
 foo2:
   - foo2
 
-# - foo2
+  # - foo2
 
-# - foo2
-# - foo2
+  # - foo2
+  # - foo2

pretty_yaml/tests/fmt/comment/map-3.snap

@@ -13,5 +13,5 @@ foo1:
 foo2:
   - foo2
 
-# first line
-# next line
+  # first line
+  # next line

pretty_yaml/tests/fmt/comment/map.snap

@@ -18,8 +18,8 @@ foo2:
   - foo: item11
     bar: item11
 
-# - foo: item22
-#   bar: item22
+  # - foo: item22
+  #   bar: item22
 
-# - foo: item33
-#   bar: item33
+  # - foo: item33
+  #   bar: item33

pretty_yaml/tests/fmt/comment/object.snap

@@ -9,6 +9,6 @@ obj:
   # before
   key: value
 
-# after
+  # after
 
-# after
+  # after

pretty_yaml/tests/fmt/comment/sequence-2.snap

@@ -12,7 +12,7 @@ source: pretty_yaml/tests/fmt.rs
 # before-after.comment
 
 - none:
-# none.comment
+  # none.comment
 - before(2 line)
 
 # before.comment

pretty_yaml/tests/fmt/comment/sequence.snap

@@ -11,6 +11,6 @@ source: pretty_yaml/tests/fmt.rs
 
 - - a
 
-# - b
+  # - b
 
-# - c
+  # - c

pretty_yaml/tests/fmt/root/example.snap

@@ -23,7 +23,7 @@ omap:
     - aardvark: African pig-like ant eater. Ugly.
     - anteater: South-American ant eater. Two species.
     - anaconda: South-American constrictor snake. Scaly.
-  # Etc.
+    # Etc.
   # Flow style
   Numbers: !!omap [one: 1, two: 2, three: 3]
 

yaml_parser/src/lib.rs

@@ -738,16 +738,21 @@ fn block_sequence(input: &mut Input) -> GreenResult {
         (
             block_sequence_entry,
             repeat(0.., (cmts_or_ws1.verify_indent(), block_sequence_entry)),
+            block_collection_trailing_trivias(input.state.indent),
         ),
     )
     .parse_next(input)
-    .map(|(first, rest): (_, Vec<_>)| {
+    .map(|(first, rest, trailing_trivias): (_, Vec<_>, _)| {
         let mut children = Vec::with_capacity(1 + rest.len());
         children.push(first);
         for (mut trivias, entry) in rest {
             children.append(&mut trivias);
             children.push(entry);
         }
+        trailing_trivias.into_iter().for_each(|(ws, comment)| {
+            children.push(ws);
+            children.push(comment);
+        });
         node(BLOCK_SEQ, children)
     })
 }
@@ -819,16 +824,21 @@ fn block_map(input: &mut Input) -> GreenResult {
                     alt((block_map_implicit_entry, block_map_explicit_entry)),
                 ),
             ),
+            block_collection_trailing_trivias(indent),
         ),
     )
     .parse_next(input)
-    .map(|(first, rest): (_, Vec<_>)| {
+    .map(|(first, rest, trailing_trivias): (_, Vec<_>, _)| {
         let mut children = Vec::with_capacity(1 + rest.len());
         children.push(first);
         for (mut trivias, entry) in rest {
             children.append(&mut trivias);
             children.push(entry);
         }
+        trailing_trivias.into_iter().for_each(|(ws, comment)| {
+            children.push(ws);
+            children.push(comment);
+        });
         node(BLOCK_MAP, children)
     })
 }
@@ -938,6 +948,17 @@ fn block_map_implicit_key(input: &mut Input) -> GreenResult {
     .map(|child| node(BLOCK_MAP_KEY, [child]))
 }
 
+fn block_collection_trailing_trivias<'s>(
+    indent: usize,
+) -> impl Parser<Input<'s>, Vec<(GreenElement, GreenElement)>, ContextError> {
+    // 1. We don't use `verify_indent` or `state.prev_indent` because they were changed after
+    //    the last entry. Comments and whitespaces will be parsed after each entry but they're
+    //    discarded because there're no entries any more, but state is still changed.
+    // 2. Top-level comments shouldn't be included in block collection.
+    let verify = verify_state(move |state| state.indent == indent && !state.document_top);
+    repeat(0.., (terminated(ws, verify), comment))
+}
+
 fn block(input: &mut Input) -> GreenResult {
     let mut bf_ctx = |input: &mut Input| -> PResult<_> { Ok(input.state.bf_ctx.clone()) };