Fix comment formatting for yielded tuples (#6603)

## Summary
Closes https://github.com/astral-sh/ruff/issues/6384, although I think
the issue was fixed already on main, for the most part.

The linked issue is around formatting expressions like:

```python
def test():
    (
        yield 
        #comment 1
        * # comment 2
        # comment 3
        test # comment 4
    )

```

On main, prior to this PR, we now format like:

```python
def test():
    (
        yield (
            # comment 1
            # comment 2
            # comment 3
            *test
        )  # comment 4
    )
```

Which strikes me as reasonable. (We can't test this, since it's a syntax
error after for our parser, despite being a syntax error in both cases
from CPython's perspective.)

Meanwhile, Black does:

```python
def test():
    (
        yield
        # comment 1
        *  # comment 2
        # comment 3
        test  # comment 4
    )
```

So our formatting differs in that we move comments between the star and
the expression above the star.

As of this PR, we also support formatting this input, which is valid:

```python
def test():
    (
        yield 
        #comment 1
        * # comment 2
        # comment 3
        test, # comment 4
        1
    )
```

Like:

```python
def test():
    (
        yield (
            # comment 1
            (
                # comment 2
                # comment 3
                *test,  # comment 4
                1,
            )
        )
    )
```

There were two fixes here: (1) marking starred comments as dangling and
formatting them properly; and (2) supporting parenthesized comments for
tuples that don't contain their own parentheses, as is often the case
for yielded tuples (previously, we hit a debug assert).

Note that this diff

## Test Plan
cargo test
This commit is contained in:
Charlie Marsh 2023-08-16 09:41:07 -04:00 committed by GitHub
parent 7ee2ae8395
commit 12f3c4c931
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GPG key ID: 4AEE18F83AFDEB23
7 changed files with 88 additions and 21 deletions

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@ -204,7 +204,7 @@ impl NeedsParentheses for ExprTuple {
}
/// Check if a tuple has already had parentheses in the input
fn is_tuple_parenthesized(tuple: &ExprTuple, source: &str) -> bool {
pub(crate) fn is_tuple_parenthesized(tuple: &ExprTuple, source: &str) -> bool {
let Some(elt) = tuple.elts.first() else {
return false;
};