Example
---
```rust
#[cfg(test)]
fn foo() {
    foo($01 + 1$0);
}
```

**Before this PR**

```rust
#[cfg(test)]
fn foo() {
    foo(fun_name());
}

fn $0fun_name() -> i32 {
    1 + 1
}
```

**After this PR**

```rust
#[cfg(test)]
fn foo() {
    foo(fun_name());
}

#[cfg(test)]
fn $0fun_name() -> i32 {
    1 + 1
}
```