1 use hir::db::HirDatabase;
2 use ra_syntax::ast::{self, AstNode};
3 use ra_syntax::{TextRange, TextUnit};
5 use crate::{Assist, AssistCtx, AssistId};
6 use super::apply_demorgan::undo_negation;
11 // This transforms if expressions of the form `if !x {A} else {B}` into `if x {B} else {A}`
12 // This also works with `!=`. This assist can only be applied with the cursor
17 // if<|> !y {A} else {B}
28 pub(crate) fn invert_if(ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
29 let expr = ctx.find_node_at_offset::<ast::IfExpr>()?;
30 let expr_range = expr.syntax().text_range();
31 let if_range = TextRange::offset_len(expr_range.start(), TextUnit::from_usize(2));
32 let cursor_in_range = ctx.frange.range.is_subrange(&if_range);
37 let cond = expr.condition()?.expr()?.syntax().clone();
38 let then_node = expr.then_branch()?.syntax().clone();
40 if let ast::ElseBranch::Block(else_block) = expr.else_branch()? {
41 let flip_cond = undo_negation(cond.clone())?;
42 let cond_range = cond.text_range();
43 let else_node = else_block.syntax();
44 let else_range = else_node.text_range();
45 let then_range = then_node.text_range();
46 ctx.add_assist(AssistId("invert_if"), "invert if branches", |edit| {
47 edit.target(if_range);
48 edit.replace(cond_range, flip_cond);
49 edit.replace(else_range, then_node.text());
50 edit.replace(then_range, else_node.text());
64 use crate::helpers::{check_assist, check_assist_not_applicable};
67 fn invert_if_remove_inequality() {
68 check_assist(invert_if, "fn f() { i<|>f x != 3 {1} else {3 + 2} }", "fn f() { i<|>f x == 3 {3 + 2} else {1} }")
72 fn invert_if_remove_not() {
73 check_assist(invert_if, "fn f() { <|>if !cond {3 * 2} else {1} }", "fn f() { <|>if cond {1} else {3 * 2} }")
77 fn invert_if_doesnt_apply_with_cursor_not_on_if() {
78 check_assist_not_applicable(invert_if, "fn f() { if !<|>cond {3 * 2} else {1} }")
82 fn invert_if_doesnt_apply_without_negated() {
83 check_assist_not_applicable(invert_if, "fn f() { i<|>f cond {3 * 2} else {1} }")