Merge #11173

11173: Allow adding partially resolved types r=Veykril a=SomeoneToIgnore

Sometimes when writing something like `let foo = Arc::new(Mutex::new(CrazyGenerics::new(HashMap::new())))`, I want/have to specify an explicit type for the expression.
Using turbofish isn't very readable and not always appreciated by guidelines, so `let foo: T` has to be filled.

To ease that, the PR enables the `add_explicit_type` assist on types that contain unknown types and some generics.
Fully unresolved types, arrays with unknown types and other known cases behave the same.

`_` placeholder was chosen to replace an unknown type:

```rust
let foo = HashMap::new();
// after assist usage, turns into
let foo: HashMap<_, _> = HashMap::new();
```

Co-authored-by: Kirill Bulatov <mail4score@gmail.com>

0 files changed, 0 insertions, 0 deletions