Unnamed repository; edit this file 'description' to name the repository.
| -rw-r--r-- | crates/ide-assists/src/handlers/remove_parentheses.rs | 122 |
1 files changed, 117 insertions, 5 deletions
diff --git a/crates/ide-assists/src/handlers/remove_parentheses.rs b/crates/ide-assists/src/handlers/remove_parentheses.rs index 9a1f9268d0..ff500ba035 100644 --- a/crates/ide-assists/src/handlers/remove_parentheses.rs +++ b/crates/ide-assists/src/handlers/remove_parentheses.rs @@ -28,7 +28,13 @@ pub(crate) fn remove_parentheses(acc: &mut Assists, ctx: &AssistContext<'_>) -> return None; } - // FIXME: check that precedence is right + let expr = parens.expr()?; + let parent = ast::Expr::cast(parens.syntax().parent()?); + let is_ok_to_remove = + parent.map_or(true, |p| ExprPrecedence::of(&expr) >= ExprPrecedence::of(&p)); + if !is_ok_to_remove { + return None; + } let delete_from_l = l_paren.text_range().start(); let delete_to_l = match l_paren.next_token() { @@ -54,6 +60,97 @@ pub(crate) fn remove_parentheses(acc: &mut Assists, ctx: &AssistContext<'_>) -> ) } +#[derive(Debug, Copy, Clone, Ord, PartialOrd, Eq, PartialEq)] +pub enum ExprPrecedence { + // N.B.: Order is important + /// Precedence is unknown + Dummy, + Closure, + Jump, + Range, + Bin(BinOpPresedence), + Prefix, + Postfix, + Paren, +} + +#[derive(Debug, Copy, Clone, Ord, PartialOrd, Eq, PartialEq)] +pub enum BinOpPresedence { + // N.B.: Order is important + /// `=`, `+=`, `-=`, `*=`, `/=`, `%=`, `|=`, `&=` + Assign, + /// `||` + LOr, + /// `&&` + LAnd, + /// `<`, `<=`, `>`, `>=`, `==` and `!=` + Cmp, + /// `|` + BitOr, + /// `^` + BitXor, + /// `&` + BitAnd, + /// `<<` and `>>` + Shift, + /// `+` and `-` + Add, + /// `*`, `/` and `%` + Mul, + /// `as` + As, +} + +impl ExprPrecedence { + pub fn of(expr: &ast::Expr) -> Self { + // Copied from <https://github.com/rust-lang/rust/blob/b6852428a8ea9728369b64b9964cad8e258403d3/compiler/rustc_ast/src/util/parser.rs#L296> + use ast::Expr::*; + + match expr { + ClosureExpr(_) => Self::Closure, + + ContinueExpr(_) | ReturnExpr(_) | YieldExpr(_) | BreakExpr(_) => Self::Jump, + + RangeExpr(_) => Self::Range, + + BinExpr(bin_expr) => bin_expr + .op_kind() + .map(|op| match op { + ast::BinaryOp::LogicOp(op) => match op { + ast::LogicOp::And => BinOpPresedence::LAnd, + ast::LogicOp::Or => BinOpPresedence::LOr, + }, + ast::BinaryOp::ArithOp(op) => match op { + ast::ArithOp::Add => BinOpPresedence::Add, + ast::ArithOp::Mul => BinOpPresedence::Mul, + ast::ArithOp::Sub => BinOpPresedence::Add, + ast::ArithOp::Div => BinOpPresedence::Mul, + ast::ArithOp::Rem => BinOpPresedence::Mul, + ast::ArithOp::Shl => BinOpPresedence::Shift, + ast::ArithOp::Shr => BinOpPresedence::Shift, + ast::ArithOp::BitXor => BinOpPresedence::BitXor, + ast::ArithOp::BitOr => BinOpPresedence::BitOr, + ast::ArithOp::BitAnd => BinOpPresedence::BitAnd, + }, + ast::BinaryOp::CmpOp(_) => BinOpPresedence::Cmp, + ast::BinaryOp::Assignment { .. } => BinOpPresedence::Assign, + }) + .map(Self::Bin) + .unwrap_or(Self::Dummy), + CastExpr(_) => Self::Bin(BinOpPresedence::As), + + BoxExpr(_) | RefExpr(_) | LetExpr(_) | PrefixExpr(_) => Self::Prefix, + + AwaitExpr(_) | CallExpr(_) | MethodCallExpr(_) | FieldExpr(_) | IndexExpr(_) + | TryExpr(_) | MacroExpr(_) => Self::Postfix, + + ArrayExpr(_) | TupleExpr(_) | Literal(_) | PathExpr(_) | ParenExpr(_) | IfExpr(_) + | WhileExpr(_) | ForExpr(_) | LoopExpr(_) | MatchExpr(_) | BlockExpr(_) + | RecordExpr(_) | UnderscoreExpr(_) => Self::Paren, + } + } +} + #[cfg(test)] mod tests { use crate::tests::{check_assist, check_assist_not_applicable}; @@ -68,14 +165,29 @@ mod tests { check_assist(remove_parentheses, r#"fn f() { (2$0) + 2; }"#, r#"fn f() { 2 + 2; }"#); } - // We should not permit assist here and yet #[test] - fn remove_parens_wrong() { + fn remove_parens_precedence() { check_assist( remove_parentheses, - r#"fn f() { $0(2 + 2) * 8; }"#, - r#"fn f() { 2 + 2 * 8; }"#, + 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] |