use hir::db::HirDatabase; use ra_syntax::{algo::non_trivia_sibling, Direction, T}; use crate::{Assist, AssistCtx, AssistId}; pub(crate) fn flip_comma(mut ctx: AssistCtx) -> Option { let comma = ctx.token_at_offset().find(|leaf| leaf.kind() == T![,])?; let prev = non_trivia_sibling(comma.into(), Direction::Prev)?; let next = non_trivia_sibling(comma.into(), Direction::Next)?; ctx.add_action(AssistId("flip_comma"), "flip comma", |edit| { edit.target(comma.range()); edit.replace(prev.range(), next.to_string()); edit.replace(next.range(), prev.to_string()); }); ctx.build() } #[cfg(test)] mod tests { use super::*; use crate::helpers::{check_assist, check_assist_target}; #[test] fn flip_comma_works_for_function_parameters() { check_assist( flip_comma, "fn foo(x: i32,<|> y: Result<(), ()>) {}", "fn foo(y: Result<(), ()>,<|> x: i32) {}", ) } #[test] fn flip_comma_target() { check_assist_target(flip_comma, "fn foo(x: i32,<|> y: Result<(), ()>) {}", ",") } }