## Summary
This PR removes the `debug_assertion` in the `Indexer` to allow
unterminated f-strings. This is mainly a fix in the development build
which now matches the release build.
The fix is simple: remove the `debug_assertion` which means that the
there could be `FStringStart` and possibly `FStringMiddle` tokens
without a corresponding f-string range in the `Indexer`. This means that
the code requesting for the f-string index need to account for the
`None` case, making the code safer.
This also updates the code which queries the `FStringRanges` to account
for the `None` case. This will happen when the `FStringStart` /
`FStringMiddle` tokens are present but the `FStringEnd` token isn't
which means that the `Indexer` won't contain the range for that
f-string.
## Test Plan
`cargo test`
Taking the following code as an example:
```python
f"{123}
```
This only emits a `FStringStart` token, but no `FStringMiddle` or
`FStringEnd` tokens.
And,
```python
f"\.png${
```
This emits a `FStringStart` and `FStringMiddle` token, but no
`FStringEnd` token.
fixes: #8065
## Summary
This PR fixes the bug where if a Notebook contained IPython syntax, then
the format command would fail. This was because the correct mode was not
being used while parsing through the formatter code path.
## Test Plan
This PR isn't the only requirement for Notebook formatting to start
working with IPython escape commands. The following PR in the stack is
required as well.
I got confused and refactored a bit, now the naming should be more
consistent. This is the basis for the range formatting work.
Chages:
* `format_module` -> `format_module_source` (format a string)
* `format_node` -> `format_module_ast` (format a program parsed into an
AST)
* Added `parse_ok_tokens` that takes `Token` instead of `Result<Token>`
* Call the source code `source` consistently
* Added a `tokens_and_ranges` helper
* `python_ast` -> `module` (because that's the type)
## Summary
The tokenizer was split into a forward and a backwards tokenizer. The
backwards tokenizer uses the same names as the forwards ones (e.g.
`next_token`). The backwards tokenizer gets the comment ranges that we
already built to skip comments.
---------
Co-authored-by: Micha Reiser <micha@reiser.io>
## Summary
The motivation here is that this enables us to implement `Ranged` in
crates that don't depend on `ruff_python_ast`.
Largely a mechanical refactor with a lot of regex, Clippy help, and
manual fixups.
## Test Plan
`cargo test`
## Summary
Previously, given:
```python
a = \
5;
```
When detecting continuations starting at the offset of the `;`, we'd
flag the previous line as a continuation. We should only flag a
continuation if there isn't leading content prior to the offset.
Closes https://github.com/astral-sh/ruff/issues/6214
