Merge #2343

2343: implement assist invert_if r=matklad a=bravomikekilo

fix [issue 2219 invert if condition](https://github.com/rust-analyzer/rust-analyzer/issues/2219)
I put the assist cursor range to `if` of the if expression, because both condition and body will be replaced. Is there any way to replace them without cover the cursor position?
@matklad 

Co-authored-by: bravomikekilo <[email protected]>

1 files changed, 13 insertions, 2 deletions

diff --git a/crates/ra_syntax/src/ast/make.rs b/crates/ra_syntax/src/ast/make.rs
index 9749327fa..40db570da 100644
--- a/crates/ra_syntax/src/ast/make.rs
+++ b/crates/ra_syntax/src/ast/make.rs
@@ -173,10 +173,21 @@ fn ast_from_text<N: AstNode>(text: &str) -> N {
 }
 
 pub mod tokens {
-    use crate::{AstNode, Parse, SourceFile, SyntaxKind::*, SyntaxToken, T};
+    use crate::{AstNode, Parse, SourceFile, SyntaxKind, SyntaxKind::*, SyntaxToken, T};
     use once_cell::sync::Lazy;
 
-    static SOURCE_FILE: Lazy<Parse<SourceFile>> = Lazy::new(|| SourceFile::parse(",\n; ;"));
+    static SOURCE_FILE: Lazy<Parse<SourceFile>> =
+        Lazy::new(|| SourceFile::parse("const C: () = (1 != 1, 2 == 2)\n;"));
+
+    pub fn op(op: SyntaxKind) -> SyntaxToken {
+        SOURCE_FILE
+            .tree()
+            .syntax()
+            .descendants_with_tokens()
+            .filter_map(|it| it.into_token())
+            .find(|it| it.kind() == op)
+            .unwrap()
+    }
 
     pub fn comma() -> SyntaxToken {
         SOURCE_FILE