Improve comments within function calls (#566)

* Update test case

* Expand call if it contains proper multiline comment

* Update test case

* Handle trailing comments on start parens

* Add space after comment in start_parens

* Handle leading comments on punctuation in Punctuated

* Update snapshot

src/formatters/functions.rs

@@ -5,7 +5,7 @@ use full_moon::ast::{
     FunctionName, Index, LastStmt, LocalFunction, MethodCall, Parameter, Prefix, Stmt, Suffix,
     TableConstructor, Value, Var,
 };
-use full_moon::tokenizer::{Token, TokenReference, TokenType};
+use full_moon::tokenizer::{Token, TokenKind, TokenReference, TokenType};
 use std::boxed::Box;
 
 #[cfg(feature = "luau")]
@@ -95,6 +95,12 @@ fn is_complex_arg(value: &Value) -> bool {
     value.to_string().trim().contains('\n')
 }
 
+// Test for singleline comments or multiline comments which span more than one line
+fn function_trivia_contains_comments(trivia: &Token) -> bool {
+    matches!(trivia.token_kind(), TokenKind::SingleLineComment)
+        || matches!(trivia.token_type(), TokenType::MultiLineComment { comment, .. } if comment.as_str().lines().count() > 1 )
+}
+
 /// Determines whether a parenthesised function call contains comments, forcing it to go multiline
 fn function_args_contains_comments(
     parentheses: &ContainedSpan,
@@ -116,11 +122,11 @@ fn function_args_contains_comments(
             trivia_util::get_expression_leading_trivia(argument.value())
                 .iter()
                 .chain(trivia_util::get_expression_trailing_trivia(argument.value()).iter())
-                .any(trivia_util::trivia_is_singleline_comment)
+                .any(function_trivia_contains_comments)
             // Punctuation contains comments
             || argument
                 .punctuation()
-                .map_or(false, |token| trivia_util::token_contains_comments_search(token, trivia_util::CommentSearch::Single))
+                .map_or(false, |token| token.leading_trivia().chain(token.trailing_trivia()).any(function_trivia_contains_comments))
         })
     }
 }
@@ -426,14 +432,25 @@ pub fn format_function_args(
                     arguments,
                 }
             } else {
-                // We don't need to worry about comments here, as if there were comments present, we would have
-                // multiline function args
-
                 // If we are hugging a table constructor with the parentheses, we use a shape increment of 2 to include the closing
                 // parentheses as well. Otherwise, we just use 1 = opening parentheses.
                 let shape_increment = if hug_table_constructor { 2 } else { 1 };
 
-                let parentheses = format_contained_span(ctx, parentheses, shape);
+                let (start_parens, end_parens) = parentheses.tokens();
+                let start_parens = format_token_reference(ctx, start_parens, shape);
+                let start_parens = if trivia_util::token_contains_trailing_comments(&start_parens)
+                    && !arguments.is_empty()
+                {
+                    start_parens.update_trailing_trivia(FormatTriviaType::Append(vec![Token::new(
+                        TokenType::spaces(1),
+                    )]))
+                } else {
+                    start_parens
+                };
+
+                let end_parens = format_token_reference(ctx, end_parens, shape);
+                let parentheses = ContainedSpan::new(start_parens, end_parens);
+
                 let mut arguments =
                     format_punctuated(ctx, arguments, shape + shape_increment, format_expression);
 

src/formatters/general.rs

@@ -14,6 +14,8 @@ use full_moon::ast::{
 use full_moon::node::Node;
 use full_moon::tokenizer::{StringLiteralQuoteType, Token, TokenKind, TokenReference, TokenType};
 
+use super::trivia::UpdateTrivia;
+
 #[derive(Debug, Clone, Copy)]
 pub enum FormatTokenType {
     Token,
@@ -496,9 +498,28 @@ where
             Some(punctuation) => {
                 // Continue adding a comma and a new line for multiline function args
                 // Also add any trailing comments we have taken from the expression
-                trailing_comments.push(create_newline_trivia(ctx));
-                let symbol = fmt_symbol!(ctx, punctuation, ",", shape)
-                    .update_trailing_trivia(FormatTriviaType::Append(trailing_comments));
+                let symbol = fmt_symbol!(ctx, punctuation, ",", shape);
+
+                let mut trailing_trivia: Vec<_> = symbol
+                    .leading_trivia()
+                    .filter(|trivia| trivia_util::trivia_is_comment(trivia))
+                    .cloned()
+                    .flat_map(|x| {
+                        // Prepend a single space beforehand
+                        vec![
+                            create_newline_trivia(ctx),
+                            create_indent_trivia(ctx, shape),
+                            x,
+                        ]
+                    })
+                    .collect();
+                trailing_trivia.append(&mut trailing_comments);
+                trailing_trivia.push(create_newline_trivia(ctx));
+
+                let symbol = symbol.update_trivia(
+                    FormatTriviaType::Replace(vec![]),
+                    FormatTriviaType::Append(trailing_trivia),
+                );
 
                 Some(symbol)
             }

tests/inputs/function-call-multiline-comment.lua

@@ -2,3 +2,25 @@
 -- no need to expand
 
 call(item, --[[param=]] false)
+
+call(--[[ we don't use it ]]true)
+
+call(
+	--[[
+		this comment spans
+		multiple lines
+	]]
+	false
+)
+
+x(
+	true,
+	90210
+	--[[
+		color wheel is time-reversed
+	]],
+	--[[ frobnikate the widget ]]
+	false,
+	true
+	--[[ spin the tesla coils ]]
+)

tests/snapshots/tests__standard@function-call-multiline-comment.lua.snap

@@ -7,3 +7,25 @@ expression: format(&contents)
 
 call(item, --[[param=]] false)
 
+call(--[[ we don't use it ]] true)
+
+call(
+	--[[
+		this comment spans
+		multiple lines
+	]]
+	false
+)
+
+x(
+	true,
+	90210,
+	--[[
+		color wheel is time-reversed
+	]]
+	--[[ frobnikate the widget ]]
+	false,
+	true
+	--[[ spin the tesla coils ]]
+)
+