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## Summary
This PR normalizes line endings inside of strings to `\n` as required by the printer.
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## Test Plan
I added a new test using `\r\n` and ran the ecosystem check. There are no remaining end of line panics.
https://gist.github.com/MichaReiser/8f36b1391ca7b48475b3a4f592d74ff4
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## Summary
This PR extends the string formatting to respect the configured quote style.
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## Test Plan
Extended the string test with new cases and set it up to run twice: Once with the `quote_style: Doube`, and once with `quote_style: Single` single and double quotes.
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## Summary
This PR implements formatting for non-f-string Strings that do not use implicit concatenation.
Docstring formatting is out of the scope of this PR.
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## Test Plan
I added a few tests for simple string literals.
## Performance
Ouch. This is hitting performance somewhat hard. This is probably because we now iterate each string a couple of times:
1. To detect if it is an implicit string continuation
2. To detect if the string contains any new lines
3. To detect the preferred quote
4. To normalize the string
Edit: I integrated the detection of newlines into the preferred quote detection so that we only iterate the string three time.
We can probably do better by merging the implicit string continuation with the quote detection and new line detection by iterating till the end of the string part and returning the offset. We then use our simple tokenizer to skip over any comments or whitespace until we find the first non trivia token. From there we keep continue doing this in a loop until we reach the end o the string. I'll leave this improvement for later.
