diff --git a/rustfmt.toml b/rustfmt.toml
index 28c8b6df6..a6b061fb0 100644
--- a/rustfmt.toml
+++ b/rustfmt.toml
@@ -14,7 +14,7 @@ reorder_imports = true
 reorder_modules = true
 remove_nested_parens = true
 match_arm_leading_pipes = "Never"
-fn_args_layout = "Tall"
+fn_params_layout = "Tall"
 edition = "2021"
 merge_derives = true
 use_try_shorthand = false
diff --git a/src/io/parser.rs b/src/io/parser.rs
index 98bc44c0b..73887448b 100644
--- a/src/io/parser.rs
+++ b/src/io/parser.rs
@@ -65,6 +65,8 @@ pub fn all_input_consumed<'a, T: 'a>(
 pub fn comment(input: Span) -> IntermediateResult<()> {
     alt((
         value((), pair(tag("%"), is_not("\n\r"))),
+        // a comment that immediately precedes the end of the line –
+        // this must come after the normal line comment above
         value((), tag("%")),
     ))(input)
 }