| use ide_db::syntax_helpers::node_ext::is_pattern_cond; |
| use syntax::{ |
| ast::{self, AstNode, BinaryOp}, |
| T, |
| }; |
| |
| use crate::{ |
| assist_context::{AssistContext, Assists}, |
| AssistId, AssistKind, |
| }; |
| // Assist: merge_nested_if |
| // |
| // This transforms if expressions of the form `if x { if y {A} }` into `if x && y {A}` |
| // This assist can only be applied with the cursor on `if`. |
| // |
| // ``` |
| // fn main() { |
| // i$0f x == 3 { if y == 4 { 1 } } |
| // } |
| // ``` |
| // -> |
| // ``` |
| // fn main() { |
| // if x == 3 && y == 4 { 1 } |
| // } |
| // ``` |
| pub(crate) fn merge_nested_if(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> { |
| let if_keyword = ctx.find_token_syntax_at_offset(T![if])?; |
| let expr = ast::IfExpr::cast(if_keyword.parent()?)?; |
| let if_range = if_keyword.text_range(); |
| let cursor_in_range = if_range.contains_range(ctx.selection_trimmed()); |
| if !cursor_in_range { |
| return None; |
| } |
| |
| //should not apply to if with else branch. |
| if expr.else_branch().is_some() { |
| return None; |
| } |
| |
| let cond = expr.condition()?; |
| //should not apply for if-let |
| if is_pattern_cond(cond.clone()) { |
| return None; |
| } |
| |
| let cond_range = cond.syntax().text_range(); |
| |
| //check if the then branch is a nested if |
| let then_branch = expr.then_branch()?; |
| let stmt = then_branch.stmt_list()?; |
| if stmt.statements().count() != 0 { |
| return None; |
| } |
| |
| let nested_if_to_merge = then_branch.tail_expr().and_then(|e| match e { |
| ast::Expr::IfExpr(e) => Some(e), |
| _ => None, |
| })?; |
| // should not apply to nested if with else branch. |
| if nested_if_to_merge.else_branch().is_some() { |
| return None; |
| } |
| let nested_if_cond = nested_if_to_merge.condition()?; |
| if is_pattern_cond(nested_if_cond.clone()) { |
| return None; |
| } |
| |
| let nested_if_then_branch = nested_if_to_merge.then_branch()?; |
| let then_branch_range = then_branch.syntax().text_range(); |
| |
| acc.add( |
| AssistId("merge_nested_if", AssistKind::RefactorRewrite), |
| "Merge nested if", |
| if_range, |
| |edit| { |
| let cond_text = if has_logic_op_or(&cond) { |
| format!("({})", cond.syntax().text()) |
| } else { |
| cond.syntax().text().to_string() |
| }; |
| |
| let nested_if_cond_text = if has_logic_op_or(&nested_if_cond) { |
| format!("({})", nested_if_cond.syntax().text()) |
| } else { |
| nested_if_cond.syntax().text().to_string() |
| }; |
| |
| let replace_cond = format!("{} && {}", cond_text, nested_if_cond_text); |
| |
| edit.replace(cond_range, replace_cond); |
| edit.replace(then_branch_range, nested_if_then_branch.syntax().text()); |
| }, |
| ) |
| } |
| |
| /// Returns whether the given if condition has logical operators. |
| fn has_logic_op_or(expr: &ast::Expr) -> bool { |
| match expr { |
| ast::Expr::BinExpr(bin_expr) => { |
| if let Some(kind) = bin_expr.op_kind() { |
| matches!(kind, BinaryOp::LogicOp(ast::LogicOp::Or)) |
| } else { |
| false |
| } |
| } |
| _ => false, |
| } |
| } |
| |
| #[cfg(test)] |
| mod tests { |
| use super::*; |
| use crate::tests::{check_assist, check_assist_not_applicable}; |
| |
| #[test] |
| fn merge_nested_if_test1() { |
| check_assist( |
| merge_nested_if, |
| "fn f() { i$0f x == 3 { if y == 4 { 1 } } }", |
| "fn f() { if x == 3 && y == 4 { 1 } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_test2() { |
| check_assist( |
| merge_nested_if, |
| "fn f() { i$0f x == 3 || y == 1 { if z == 4 { 1 } } }", |
| "fn f() { if (x == 3 || y == 1) && z == 4 { 1 } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_test3() { |
| check_assist( |
| merge_nested_if, |
| "fn f() { i$0f x == 3 && y == 1 { if z == 4 { 1 } } }", |
| "fn f() { if x == 3 && y == 1 && z == 4 { 1 } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_test4() { |
| check_assist( |
| merge_nested_if, |
| "fn f() { i$0f x == 3 && y == 1 { if z == 4 && q == 3 { 1 } } }", |
| "fn f() { if x == 3 && y == 1 && z == 4 && q == 3 { 1 } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_test5() { |
| check_assist( |
| merge_nested_if, |
| "fn f() { i$0f x == 3 && y == 1 { if z == 4 || q == 3 { 1 } } }", |
| "fn f() { if x == 3 && y == 1 && (z == 4 || q == 3) { 1 } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_test6() { |
| check_assist( |
| merge_nested_if, |
| "fn f() { i$0f x == 3 || y == 1 { if z == 4 || q == 3 { 1 } } }", |
| "fn f() { if (x == 3 || y == 1) && (z == 4 || q == 3) { 1 } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_test7() { |
| check_assist( |
| merge_nested_if, |
| "fn f() { i$0f x == 3 || y == 1 { if z == 4 && q == 3 { 1 } } }", |
| "fn f() { if (x == 3 || y == 1) && z == 4 && q == 3 { 1 } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_do_not_apply_to_if_with_else_branch() { |
| check_assist_not_applicable( |
| merge_nested_if, |
| "fn f() { i$0f x == 3 { if y == 4 { 1 } } else { 2 } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_do_not_apply_to_nested_if_with_else_branch() { |
| check_assist_not_applicable( |
| merge_nested_if, |
| "fn f() { i$0f x == 3 { if y == 4 { 1 } else { 2 } } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_do_not_apply_to_if_let() { |
| check_assist_not_applicable( |
| merge_nested_if, |
| "fn f() { i$0f let Some(x) = y { if x == 4 { 1 } } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_do_not_apply_to_nested_if_let() { |
| check_assist_not_applicable( |
| merge_nested_if, |
| "fn f() { i$0f y == 0 { if let Some(x) = y { 1 } } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_do_not_apply_to_if_with_else_branch_and_nested_if() { |
| check_assist_not_applicable( |
| merge_nested_if, |
| "fn f() { i$0f x == 3 { if y == 4 { 1 } } else { if z == 5 { 2 } } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_do_not_apply_with_cursor_not_on_if() { |
| check_assist_not_applicable(merge_nested_if, "fn f() { if $0x==0 { if y == 3 { 1 } } }") |
| } |
| |
| #[test] |
| fn merge_nested_if_do_not_apply_with_mulpiple_if() { |
| check_assist_not_applicable( |
| merge_nested_if, |
| "fn f() { i$0f x == 0 { if y == 3 { 1 } else if y == 4 { 2 } } }", |
| ) |
| } |
| #[test] |
| fn merge_nested_if_do_not_apply_with_not_only_has_nested_if() { |
| check_assist_not_applicable( |
| merge_nested_if, |
| "fn f() { i$0f x == 0 { if y == 3 { foo(); } foo(); } }", |
| ) |
| } |
| |
| #[test] |
| fn merge_nested_if_do_not_apply_with_multiply_nested_if() { |
| check_assist_not_applicable( |
| merge_nested_if, |
| "fn f() { i$0f x == 0 { if y == 3 { foo(); } if z == 3 { 2 } } }", |
| ) |
| } |
| } |