rust/crates/ide-assists/src/handlers/remove_parentheses.rs
2022-12-08 18:54:08 +00:00

92 lines
3.0 KiB
Rust

use syntax::{ast, AstNode};
use crate::{AssistContext, AssistId, AssistKind, Assists};
// Assist: remove_parentheses
//
// Removes redundant parentheses.
//
// ```
// fn main() {
// _ = $0(2) + 2;
// }
// ```
// ->
// ```
// fn main() {
// _ = 2 + 2;
// }
// ```
pub(crate) fn remove_parentheses(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
let parens = ctx.find_node_at_offset::<ast::ParenExpr>()?;
let cursor_in_range =
parens.l_paren_token()?.text_range().contains_range(ctx.selection_trimmed())
|| parens.r_paren_token()?.text_range().contains_range(ctx.selection_trimmed());
if !cursor_in_range {
return None;
}
let expr = parens.expr()?;
let parent = ast::Expr::cast(parens.syntax().parent()?);
let is_ok_to_remove = expr.precedence() >= parent.as_ref().and_then(ast::Expr::precedence);
if !is_ok_to_remove {
return None;
}
let target = parens.syntax().text_range();
acc.add(
AssistId("remove_parentheses", AssistKind::Refactor),
"Remove redundant parentheses",
target,
|builder| builder.replace_ast(parens.into(), expr),
)
}
#[cfg(test)]
mod tests {
use crate::tests::{check_assist, check_assist_not_applicable};
use super::*;
#[test]
fn remove_parens_simple() {
check_assist(remove_parentheses, r#"fn f() { $0(2) + 2; }"#, r#"fn f() { 2 + 2; }"#);
check_assist(remove_parentheses, r#"fn f() { ($02) + 2; }"#, r#"fn f() { 2 + 2; }"#);
check_assist(remove_parentheses, r#"fn f() { (2)$0 + 2; }"#, r#"fn f() { 2 + 2; }"#);
check_assist(remove_parentheses, r#"fn f() { (2$0) + 2; }"#, r#"fn f() { 2 + 2; }"#);
}
#[test]
fn remove_parens_precedence() {
check_assist(
remove_parentheses,
r#"fn f() { $0(2 * 3) + 1; }"#,
r#"fn f() { 2 * 3 + 1; }"#,
);
check_assist(remove_parentheses, r#"fn f() { ( $0(2) ); }"#, r#"fn f() { ( 2 ); }"#);
check_assist(remove_parentheses, r#"fn f() { $0(2?)?; }"#, r#"fn f() { 2??; }"#);
check_assist(remove_parentheses, r#"fn f() { f(($02 + 2)); }"#, r#"fn f() { f(2 + 2); }"#);
check_assist(
remove_parentheses,
r#"fn f() { (1<2)&&$0(3>4); }"#,
r#"fn f() { (1<2)&&3>4; }"#,
);
}
#[test]
fn remove_parens_doesnt_apply_precedence() {
check_assist_not_applicable(remove_parentheses, r#"fn f() { $0(2 + 2) * 8; }"#);
check_assist_not_applicable(remove_parentheses, r#"fn f() { $0(2 + 2).f(); }"#);
check_assist_not_applicable(remove_parentheses, r#"fn f() { $0(2 + 2).await; }"#);
check_assist_not_applicable(remove_parentheses, r#"fn f() { $0!(2..2); }"#);
}
#[test]
fn remove_parens_doesnt_apply_with_cursor_not_on_paren() {
check_assist_not_applicable(remove_parentheses, r#"fn f() { (2 +$0 2) }"#);
check_assist_not_applicable(remove_parentheses, r#"fn f() {$0 (2 + 2) }"#);
}
}