use itertools::Itertools; use ra_fmt::{compute_ws, extract_trivial_expression}; use syntax::{ algo::{find_covering_element, non_trivia_sibling}, ast::{self, AstNode, AstToken}, Direction, NodeOrToken, SourceFile, SyntaxKind::{self, WHITESPACE}, SyntaxNode, SyntaxToken, TextRange, TextSize, T, }; use text_edit::{TextEdit, TextEditBuilder}; // Feature: Join Lines // // Join selected lines into one, smartly fixing up whitespace, trailing commas, and braces. // // |=== // | Editor | Action Name // // | VS Code | **Rust Analyzer: Join lines** // |=== pub fn join_lines(file: &SourceFile, range: TextRange) -> TextEdit { let range = if range.is_empty() { let syntax = file.syntax(); let text = syntax.text().slice(range.start()..); let pos = match text.find_char('\n') { None => return TextEdit::builder().finish(), Some(pos) => pos, }; TextRange::at(range.start() + pos, TextSize::of('\n')) } else { range }; let node = match find_covering_element(file.syntax(), range) { NodeOrToken::Node(node) => node, NodeOrToken::Token(token) => token.parent(), }; let mut edit = TextEdit::builder(); for token in node.descendants_with_tokens().filter_map(|it| it.into_token()) { let range = match range.intersect(token.text_range()) { Some(range) => range, None => continue, } - token.text_range().start(); let text = token.text(); for (pos, _) in text[range].bytes().enumerate().filter(|&(_, b)| b == b'\n') { let pos: TextSize = (pos as u32).into(); let off = token.text_range().start() + range.start() + pos; if !edit.invalidates_offset(off) { remove_newline(&mut edit, &token, off); } } } edit.finish() } fn remove_newline(edit: &mut TextEditBuilder, token: &SyntaxToken, offset: TextSize) { if token.kind() != WHITESPACE || token.text().bytes().filter(|&b| b == b'\n').count() != 1 { // The node is either the first or the last in the file let suff = &token.text()[TextRange::new( offset - token.text_range().start() + TextSize::of('\n'), TextSize::of(token.text().as_str()), )]; let spaces = suff.bytes().take_while(|&b| b == b' ').count(); edit.replace(TextRange::at(offset, ((spaces + 1) as u32).into()), " ".to_string()); return; } // The node is between two other nodes let prev = token.prev_sibling_or_token().unwrap(); let next = token.next_sibling_or_token().unwrap(); if is_trailing_comma(prev.kind(), next.kind()) { // Removes: trailing comma, newline (incl. surrounding whitespace) edit.delete(TextRange::new(prev.text_range().start(), token.text_range().end())); return; } if prev.kind() == T![,] && next.kind() == T!['}'] { // Removes: comma, newline (incl. surrounding whitespace) let space = if let Some(left) = prev.prev_sibling_or_token() { compute_ws(left.kind(), next.kind()) } else { " " }; edit.replace( TextRange::new(prev.text_range().start(), token.text_range().end()), space.to_string(), ); return; } if let (Some(_), Some(next)) = ( prev.as_token().cloned().and_then(ast::Comment::cast), next.as_token().cloned().and_then(ast::Comment::cast), ) { // Removes: newline (incl. surrounding whitespace), start of the next comment edit.delete(TextRange::new( token.text_range().start(), next.syntax().text_range().start() + TextSize::of(next.prefix()), )); return; } // Special case that turns something like: // // ``` // my_function({<|> // // }) // ``` // // into `my_function()` if join_single_expr_block(edit, token).is_some() { return; } // ditto for // // ``` // use foo::{<|> // bar // }; // ``` if join_single_use_tree(edit, token).is_some() { return; } // Remove newline but add a computed amount of whitespace characters edit.replace(token.text_range(), compute_ws(prev.kind(), next.kind()).to_string()); } fn has_comma_after(node: &SyntaxNode) -> bool { match non_trivia_sibling(node.clone().into(), Direction::Next) { Some(n) => n.kind() == T![,], _ => false, } } fn join_single_expr_block(edit: &mut TextEditBuilder, token: &SyntaxToken) -> Option<()> { let block_expr = ast::BlockExpr::cast(token.parent())?; if !block_expr.is_standalone() { return None; } let expr = extract_trivial_expression(&block_expr)?; let block_range = block_expr.syntax().text_range(); let mut buf = expr.syntax().text().to_string(); // Match block needs to have a comma after the block if let Some(match_arm) = block_expr.syntax().parent().and_then(ast::MatchArm::cast) { if !has_comma_after(match_arm.syntax()) { buf.push(','); } } edit.replace(block_range, buf); Some(()) } fn join_single_use_tree(edit: &mut TextEditBuilder, token: &SyntaxToken) -> Option<()> { let use_tree_list = ast::UseTreeList::cast(token.parent())?; let (tree,) = use_tree_list.use_trees().collect_tuple()?; edit.replace(use_tree_list.syntax().text_range(), tree.syntax().text().to_string()); Some(()) } fn is_trailing_comma(left: SyntaxKind, right: SyntaxKind) -> bool { matches!((left, right), (T![,], T![')']) | (T![,], T![']'])) } #[cfg(test)] mod tests { use syntax::SourceFile; use test_utils::{add_cursor, assert_eq_text, extract_offset, extract_range}; use super::*; fn check_join_lines(before: &str, after: &str) { let (before_cursor_pos, before) = extract_offset(before); let file = SourceFile::parse(&before).ok().unwrap(); let range = TextRange::empty(before_cursor_pos); let result = join_lines(&file, range); let actual = { let mut actual = before.to_string(); result.apply(&mut actual); actual }; let actual_cursor_pos = result .apply_to_offset(before_cursor_pos) .expect("cursor position is affected by the edit"); let actual = add_cursor(&actual, actual_cursor_pos); assert_eq_text!(after, &actual); } #[test] fn test_join_lines_comma() { check_join_lines( r" fn foo() { <|>foo(1, ) } ", r" fn foo() { <|>foo(1) } ", ); } #[test] fn test_join_lines_lambda_block() { check_join_lines( r" pub fn reparse(&self, edit: &AtomTextEdit) -> File { <|>self.incremental_reparse(edit).unwrap_or_else(|| { self.full_reparse(edit) }) } ", r" pub fn reparse(&self, edit: &AtomTextEdit) -> File { <|>self.incremental_reparse(edit).unwrap_or_else(|| self.full_reparse(edit)) } ", ); } #[test] fn test_join_lines_block() { check_join_lines( r" fn foo() { foo(<|>{ 92 }) }", r" fn foo() { foo(<|>92) }", ); } #[test] fn test_join_lines_diverging_block() { let before = r" fn foo() { loop { match x { 92 => <|>{ continue; } } } } "; let after = r" fn foo() { loop { match x { 92 => <|>continue, } } } "; check_join_lines(before, after); } #[test] fn join_lines_adds_comma_for_block_in_match_arm() { check_join_lines( r" fn foo(e: Result) { match e { Ok(u) => <|>{ u.foo() } Err(v) => v, } }", r" fn foo(e: Result) { match e { Ok(u) => <|>u.foo(), Err(v) => v, } }", ); } #[test] fn join_lines_multiline_in_block() { check_join_lines( r" fn foo() { match ty { <|> Some(ty) => { match ty { _ => false, } } _ => true, } } ", r" fn foo() { match ty { <|> Some(ty) => match ty { _ => false, }, _ => true, } } ", ); } #[test] fn join_lines_keeps_comma_for_block_in_match_arm() { // We already have a comma check_join_lines( r" fn foo(e: Result) { match e { Ok(u) => <|>{ u.foo() }, Err(v) => v, } }", r" fn foo(e: Result) { match e { Ok(u) => <|>u.foo(), Err(v) => v, } }", ); // comma with whitespace between brace and , check_join_lines( r" fn foo(e: Result) { match e { Ok(u) => <|>{ u.foo() } , Err(v) => v, } }", r" fn foo(e: Result) { match e { Ok(u) => <|>u.foo() , Err(v) => v, } }", ); // comma with newline between brace and , check_join_lines( r" fn foo(e: Result) { match e { Ok(u) => <|>{ u.foo() } , Err(v) => v, } }", r" fn foo(e: Result) { match e { Ok(u) => <|>u.foo() , Err(v) => v, } }", ); } #[test] fn join_lines_keeps_comma_with_single_arg_tuple() { // A single arg tuple check_join_lines( r" fn foo() { let x = (<|>{ 4 },); }", r" fn foo() { let x = (<|>4,); }", ); // single arg tuple with whitespace between brace and comma check_join_lines( r" fn foo() { let x = (<|>{ 4 } ,); }", r" fn foo() { let x = (<|>4 ,); }", ); // single arg tuple with newline between brace and comma check_join_lines( r" fn foo() { let x = (<|>{ 4 } ,); }", r" fn foo() { let x = (<|>4 ,); }", ); } #[test] fn test_join_lines_use_items_left() { // No space after the '{' check_join_lines( r" <|>use syntax::{ TextSize, TextRange, };", r" <|>use syntax::{TextSize, TextRange, };", ); } #[test] fn test_join_lines_use_items_right() { // No space after the '}' check_join_lines( r" use syntax::{ <|> TextSize, TextRange };", r" use syntax::{ <|> TextSize, TextRange};", ); } #[test] fn test_join_lines_use_items_right_comma() { // No space after the '}' check_join_lines( r" use syntax::{ <|> TextSize, TextRange, };", r" use syntax::{ <|> TextSize, TextRange};", ); } #[test] fn test_join_lines_use_tree() { check_join_lines( r" use syntax::{ algo::<|>{ find_token_at_offset, }, ast, };", r" use syntax::{ algo::<|>find_token_at_offset, ast, };", ); } #[test] fn test_join_lines_normal_comments() { check_join_lines( r" fn foo() { // Hello<|> // world! } ", r" fn foo() { // Hello<|> world! } ", ); } #[test] fn test_join_lines_doc_comments() { check_join_lines( r" fn foo() { /// Hello<|> /// world! } ", r" fn foo() { /// Hello<|> world! } ", ); } #[test] fn test_join_lines_mod_comments() { check_join_lines( r" fn foo() { //! Hello<|> //! world! } ", r" fn foo() { //! Hello<|> world! } ", ); } #[test] fn test_join_lines_multiline_comments_1() { check_join_lines( r" fn foo() { // Hello<|> /* world! */ } ", r" fn foo() { // Hello<|> world! */ } ", ); } #[test] fn test_join_lines_multiline_comments_2() { check_join_lines( r" fn foo() { // The<|> /* quick brown fox! */ } ", r" fn foo() { // The<|> quick brown fox! */ } ", ); } fn check_join_lines_sel(before: &str, after: &str) { let (sel, before) = extract_range(before); let parse = SourceFile::parse(&before); let result = join_lines(&parse.tree(), sel); let actual = { let mut actual = before.to_string(); result.apply(&mut actual); actual }; assert_eq_text!(after, &actual); } #[test] fn test_join_lines_selection_fn_args() { check_join_lines_sel( r" fn foo() { <|>foo(1, 2, 3, <|>) } ", r" fn foo() { foo(1, 2, 3) } ", ); } #[test] fn test_join_lines_selection_struct() { check_join_lines_sel( r" struct Foo <|>{ f: u32, }<|> ", r" struct Foo { f: u32 } ", ); } #[test] fn test_join_lines_selection_dot_chain() { check_join_lines_sel( r" fn foo() { join(<|>type_params.type_params() .filter_map(|it| it.name()) .map(|it| it.text())<|>) }", r" fn foo() { join(type_params.type_params().filter_map(|it| it.name()).map(|it| it.text())) }", ); } #[test] fn test_join_lines_selection_lambda_block_body() { check_join_lines_sel( r" pub fn handle_find_matching_brace() { params.offsets .map(|offset| <|>{ world.analysis().matching_brace(&file, offset).unwrap_or(offset) }<|>) .collect(); }", r" pub fn handle_find_matching_brace() { params.offsets .map(|offset| world.analysis().matching_brace(&file, offset).unwrap_or(offset)) .collect(); }", ); } #[test] fn test_join_lines_commented_block() { check_join_lines( r" fn main() { let _ = { // <|>foo // bar 92 }; } ", r" fn main() { let _ = { // <|>foo bar 92 }; } ", ) } #[test] fn join_lines_mandatory_blocks_block() { check_join_lines( r" <|>fn foo() { 92 } ", r" <|>fn foo() { 92 } ", ); check_join_lines( r" fn foo() { <|>if true { 92 } } ", r" fn foo() { <|>if true { 92 } } ", ); check_join_lines( r" fn foo() { <|>loop { 92 } } ", r" fn foo() { <|>loop { 92 } } ", ); check_join_lines( r" fn foo() { <|>unsafe { 92 } } ", r" fn foo() { <|>unsafe { 92 } } ", ); } }