### What it does Checks for calls to `.expect(&format!(...))`, `.expect(foo(..))`, etc., and suggests to use `unwrap_or_else` instead ### Why is this bad? The function will always be called. ### Known problems If the function has side-effects, not calling it will change the semantics of the program, but you shouldn't rely on that anyway. ### Example ``` foo.expect(&format!("Err {}: {}", err_code, err_msg)); // or foo.expect(format!("Err {}: {}", err_code, err_msg).as_str()); ``` Use instead: ``` foo.unwrap_or_else(|| panic!("Err {}: {}", err_code, err_msg)); ```