Fix expect_fun_call producing invalid suggestions (#15122)

Previously expect_fun_call would too eagerly convert cases like
`foo.expect(if | block | match)` into `foo.unwrap_or_else`.
Additionally, it would also add to_string() even though the argument is
being passed into format!() which can accept a &str. I also discovered
some other cases where this lint would either produce invalid results,
or be triggered unnecessarily:

- Clippy would suggest changing expect to unwrap_or_else even if the
expression inside expect contains a return statement
- opt.expect(const_fn()) no longer triggers the lint
- The lint would always add braces to the closure body, even if the body
of expect is a single expression
- opt.expect({"literal"}) used to get turned into
```opt.unwrap_or_else(|| panic!("{}", {"literal"}.to_string()))```

Fixes rust-lang/rust-clippy#15056

changelog: [`expect_fun_call`]: fix expect_fun_call producing invalid
suggestions

0 files changed, 0 insertions, 0 deletions