Merge #6731

6731: Add replace_match_with_if_let assist r=matklad a=Veykril

Basically the counterpart to `replace_if_let_with_match`, I personally sometimes want to replace matches like
```rust
match foo {
    pat => expr,
    _ => (),
}
``` 
into the corresponding
```rust
if let pat = foo {
    expr
}
```
which is the main reasoning behind this.
I put this into the same file as `replace_if_let_with_match` because the are complementing each other and I would probably rename the file to something like `replace_if_let_match` but I didn't do that for now because I was unsure whether git would still view this as a rename or not due to the amount of changes in the file so that the diff is still properly visible for now.

Co-authored-by: Lukas Wirth <[email protected]>

1 files changed, 11 insertions, 2 deletions

diff --git a/crates/syntax/src/ast/make.rs b/crates/syntax/src/ast/make.rs
index 876659a2b..cc09b77a5 100644
--- a/crates/syntax/src/ast/make.rs
+++ b/crates/syntax/src/ast/make.rs
@@ -171,8 +171,17 @@ pub fn expr_return() -> ast::Expr {
 pub fn expr_match(expr: ast::Expr, match_arm_list: ast::MatchArmList) -> ast::Expr {
     expr_from_text(&format!("match {} {}", expr, match_arm_list))
 }
-pub fn expr_if(condition: ast::Condition, then_branch: ast::BlockExpr) -> ast::Expr {
-    expr_from_text(&format!("if {} {}", condition, then_branch))
+pub fn expr_if(
+    condition: ast::Condition,
+    then_branch: ast::BlockExpr,
+    else_branch: Option<ast::ElseBranch>,
+) -> ast::Expr {
+    let else_branch = match else_branch {
+        Some(ast::ElseBranch::Block(block)) => format!("else {}", block),
+        Some(ast::ElseBranch::IfExpr(if_expr)) => format!("else {}", if_expr),
+        None => String::new(),
+    };
+    expr_from_text(&format!("if {} {} {}", condition, then_branch, else_branch))
 }
 pub fn expr_prefix(op: SyntaxKind, expr: ast::Expr) -> ast::Expr {
     let token = token(op);