## Summary
Resolves#9467
Parse quoted annotations as if the string content is inside parenthesis.
With this logic `x` and `y` in this example are equal:
```python
y: """
int |
str
"""
z: """(
int |
str
)
"""
```
Also this rule only applies to triple
quotes([link](https://github.com/python/typing-council/issues/9#issuecomment-1890808610)).
This PR is based on the
[comments](https://github.com/astral-sh/ruff/issues/9467#issuecomment-2579180991)
on the issue.
I did one extra change, since we don't want any indentation tokens I am
setting the `State::Other` as the initial state of the Lexer.
Remaining work:
- [x] Add a test case for red-knot.
- [x] Add more tests.
## Test Plan
Added a test which previously failed because quoted annotation contained
indentation.
Added an mdtest for red-knot.
Updated previous test.
Co-authored-by: Dhruv Manilawala <dhruvmanila@gmail.com>
Co-authored-by: Micha Reiser <micha@reiser.io>
## Summary
This PR splits the re-lexing logic into two parts:
1. `TokenSource`: The token source will be responsible to find the
position the lexer needs to be moved to
2. `Lexer`: The lexer will be responsible to reduce the nesting level
and move itself to the new position if recovered from a parenthesized
context
This split makes it easy to find the new lexer position without needing
to implement the backwards lexing logic again which would need to handle
cases involving:
* Different kinds of newlines
* Line continuation character(s)
* Comments
* Whitespaces
### F-strings
This change did reveal one thing about re-lexing f-strings. Consider the
following example:
```py
f'{'
# ^
f'foo'
```
Here, the quote as highlighted by the caret (`^`) is the start of a
string inside an f-string expression. This is unterminated string which
means the token emitted is actually `Unknown`. The parser tries to
recover from it but there's no newline token in the vector so the new
logic doesn't recover from it. The previous logic does recover because
it's looking at the raw characters instead.
The parser would be at `FStringStart` (the one for the second line) when
it calls into the re-lexing logic to recover from an unterminated
f-string on the first line. So, moving backwards the first character
encountered is a newline character but the first token encountered is an
`Unknown` token.
This is improved with #12067fixes: #12046fixes: #12036
## Test Plan
Update the snapshot and validate the changes.
## Summary
This PR fixes the lexer logic to **not** consume the newline character
for an unterminated string literal.
Currently, the lexer would consume it to be part of the string itself
but that would be bad for recovery because then the lexer wouldn't emit
the newline token ever. This PR fixes that to avoid consuming the
newline character in that case.
This was discovered during https://github.com/astral-sh/ruff/pull/12060.
## Test Plan
Update the snapshots and validate them.
## Summary
This PR fixes a bug introduced in
https://github.com/astral-sh/ruff/pull/12008 which didn't consider the
two character newline after the line continuation character.
For example, consider the following code highlighted with whitespaces:
```py
call(foo # comment \\r\n
\r\n
def bar():\r\n
....pass\r\n
```
The lexer is at `def` when it's running the re-lexing logic and trying
to move back to a newline character. It encounters `\n` and it's being
escaped (incorrect) but `\r` is being escaped, so it moves the lexer to
`\n` character. This creates an overlap in token ranges which causes the
panic.
```
Name 0..4
Lpar 4..5
Name 5..8
Comment 9..20
NonLogicalNewline 20..22 <-- overlap between
Newline 21..22 <-- these two tokens
NonLogicalNewline 22..23
Def 23..26
...
```
fixes: #12028
## Test Plan
Add a test case with line continuation and windows style newline
character.
## Summary
This PR updates the unterminated string error range to not include the
final newline character.
This is a follow-up to #12016 and required for #12019
This is not done for when the unterminated string goes till the end of
file (not a newline character). The unterminated f-string range is
correct.
### Why is this required for #12019 ?
Because otherwise the token ranges will overlap. For example:
```py
f"{"
f"{foo!r"
```
Here, the re-lexing logic recovers from an unterminated f-string and
thus emitting a `Newline` token for the one at the end of the first
line. But, currently the `Unknown` and the `Newline` token would overlap
because the `Unknown` token (unterminated string literal) range would
include the newline character.
## Test Plan
Update and validate the snapshot.
## Summary
This PR fixes the range highlighted for the line continuation error.
Previously, it would highlight an incorrect range:
```
1 | call(a, b, \\\
| ^^ Syntax Error: unexpected character after line continuation character
2 |
3 | def bar():
|
```
And now:
```
|
1 | call(a, b, \\\
| ^ Syntax Error: unexpected character after line continuation character
2 |
3 | def bar():
|
```
This is implemented by avoiding to update the token range for the
`Unknown` token which is emitted when there's a lexical error. Instead,
the `push_error` helper method will be responsible to update the range
to the error location.
This actually becomes a requirement which can be seen in follow-up PRs.
## Test Plan
Update and validate the snapshot.
## Summary
This PR fixes a bug where the re-lexing logic didn't consider the line
continuation character being present before the newline character. This
meant that the lexer was being moved back to the newline character which
is actually ignored via `\`.
Considering the following code:
```py
f'middle {'string':\
'format spec'}
```
The old token stream is:
```
...
Colon 18..19
FStringMiddle 19..29 (flags = F_STRING)
Newline 20..21
Indent 21..29
String 29..42
Rbrace 42..43
...
```
Notice how the ranges are overlapping between the `FStringMiddle` token
and the tokens emitted after moving the lexer backwards.
After this fix, the new token stream which is without moving the lexer
backwards in this scenario:
```
FStringStart 0..2 (flags = F_STRING)
FStringMiddle 2..9 (flags = F_STRING)
Lbrace 9..10
String 10..18
Colon 18..19
FStringMiddle 19..29 (flags = F_STRING)
FStringEnd 29..30 (flags = F_STRING)
Name 30..36
Name 37..41
Unknown 41..44
Newline 44..45
```
fixes: #12004
## Test Plan
Add test cases and update the snapshots.
## Summary
This PR does some housekeeping into moving certain structs into related
modules. Specifically,
1. Move `LexicalError` from `lexer.rs` to `error.rs` which also contains
the `ParseError`
2. Move `Token`, `TokenFlags` and `TokenValue` from `lexer.rs` to
`token.rs`
## Summary
This PR removes the duplication around `is_trivia` functions.
There are two of them in the codebase:
1. In `pycodestyle`, it's for newline, indent, dedent, non-logical
newline and comment
2. In the parser, it's for non-logical newline and comment
The `TokenKind::is_trivia` method used (1) but that's not correct in
that context. So, this PR introduces a new `is_non_logical_token` helper
method for the `pycodestyle` crate and updates the
`TokenKind::is_trivia` implementation with (2).
This also means we can remove `Token::is_trivia` method and the
standalone `token_source::is_trivia` function and use the one on
`TokenKind`.
## Test Plan
`cargo insta test`
## Summary
This PR avoids moving back the lexer for a triple-quoted f-string during
the re-lexing phase.
The reason this is a problem is that for a triple-quoted f-string the
newlines are part of the f-string itself, specifically they'll be part
of the `FStringMiddle` token. So, if we moved the lexer back, there
would be a `Newline` token whose range would be in between an
`FStringMiddle` token. This creates a panic in downstream usage.
fixes: #11937
## Test Plan
Add test cases and validate the snapshots.
## Summary
This PR updates the re-lexing logic to avoid consuming the trailing
whitespace and move the lexer explicitly to the last newline character
encountered while moving backwards.
Consider the following code snippet as taken from the test case
highlighted with whitespace (`.`) and newline (`\n`) characters:
```py
# There are trailing whitespace before the newline character but those whitespaces are
# part of the comment token
f"""hello {x # comment....\n
# ^
y = 1\n
```
The parser is at `y` when it's trying to recover from an unclosed `{`,
so it calls into the re-lexing logic which tries to move the lexer back
to the end of the previous line. But, as it consumed all whitespaces it
moved the lexer to the location marked by `^` in the above code snippet.
But, those whitespaces are part of the comment token. This means that
the range for the two tokens were overlapping which introduced the
panic.
Note that this is only a bug when there's a comment with a trailing
whitespace otherwise it's fine to move the lexer to the whitespace
character. This is because the lexer would just skip the whitespace
otherwise. Nevertheless, this PR updates the logic to move it explicitly
to the newline character in all cases.
fixes: #11929
## Test Plan
Add test cases and update the snapshot. Make sure that it doesn't panic
on the code snippet in the linked issue.
## Summary
This PR implements the re-lexing logic in the parser.
This logic is only applied when recovering from an error during list
parsing. The logic is as follows:
1. During list parsing, if an unexpected token is encountered and it
detects that an outer context can understand it and thus recover from
it, it invokes the re-lexing logic in the lexer
2. This logic first checks if the lexer is in a parenthesized context
and returns if it's not. Thus, the logic is a no-op if the lexer isn't
in a parenthesized context
3. It then reduces the nesting level by 1. It shouldn't reset it to 0
because otherwise the recovery from nested list parsing will be
incorrect
4. Then, it tries to find last newline character going backwards from
the current position of the lexer. This avoids any whitespaces but if it
encounters any character other than newline or whitespace, it aborts.
5. Now, if there's a newline character, then it needs to be re-lexed in
a logical context which means that the lexer needs to emit it as a
`Newline` token instead of `NonLogicalNewline`.
6. If the re-lexing gives a different token than the current one, the
token source needs to update it's token collection to remove all the
tokens which comes after the new current position.
It turns out that the list parsing isn't that happy with the results so
it requires some re-arranging such that the following two errors are
raised correctly:
1. Expected comma
2. Recovery context error
For (1), the following scenarios needs to be considered:
* Missing comma between two elements
* Half parsed element because the grammar doesn't allow it (for example,
named expressions)
For (2), the following scenarios needs to be considered:
1. If the parser is at a comma which means that there's a missing
element otherwise the comma would've been consumed by the first `eat`
call above. And, the parser doesn't take the re-lexing route on a comma
token.
2. If it's the first element and the current token is not a comma which
means that it's an invalid element.
resolves: #11640
## Test Plan
- [x] Update existing test snapshots and validate them
- [x] Add additional test cases specific to the re-lexing logic and
validate the snapshots
- [x] Run the fuzzer on 3000+ valid inputs
- [x] Run the fuzzer on invalid inputs
- [x] Run the parser on various open source projects
- [x] Make sure the ecosystem changes are none
## Summary
This PR re-uses the `ruff_python_trivia::is_python_whitespace` in the
lexer instead of defining its own. This was mainly to avoid circular
dependency which was resolved in #11261.
## Summary
This PR fixes a bug where the lexer didn't consider the BOM into the
start offset.
fixes: #11731
## Test Plan
Add multiple test cases which involves BOM character in the source for
the lexer and verify the snapshot.
## Summary
This PR updates the lexer checkpoint to store the cursor offset instead
of cloning the cursor itself. This reduces the size of `LexerCheckpoint`
from 136 to 112 bytes and also removes the need for lifetime.
## Test Plan
`cargo insta test`
## Summary
This PR removes the following dependencies from the `ruff_python_parser`
crate:
* `anyhow` (moved to dev dependencies)
* `is-macro`
* `itertools`
The main motivation is that they aren't used much.
Additionally, it updates the return type of `parse_type_annotation` to
use a more specific `ParseError` instead of the generic `anyhow::Error`.
## Test Plan
`cargo insta test`
## Summary
This PR re-orders the lexer methods in the following order:
1. `next_token`
2. `lex_token`
3. `eat_indentation`
4. `handle_indentation`
5. `skip_whitespace`
6. `consume_ascii_character`
7. `try_single_char_prefix`
8. `try_double_char_prefix`
9. `lex_identifier`
10. `lex_fstring_start`
11. `lex_fstring_middle_or_end`
12. `lex_string`
13. `lex_number`
14. `lex_number_radix`
15. `lex_decimal_number`
16. `radix_run`
17. `lex_comment`
18. `lex_ipython_escape_command`
19. `consume_end`
Following was considered for the ordering:
* 1 is the main entry point which delegates to 2
* 3, 4, 5 are all related to whitespace which is done first
* 6 is the entrypoint for an ascii character which delegates to 9, 12,
13, 17, 18, 19
* Others are grouped around similar kind of methods
## Summary
This PR updates the entire parser stack in multiple ways:
### Make the lexer lazy
* https://github.com/astral-sh/ruff/pull/11244
* https://github.com/astral-sh/ruff/pull/11473
Previously, Ruff's lexer would act as an iterator. The parser would
collect all the tokens in a vector first and then process the tokens to
create the syntax tree.
The first task in this project is to update the entire parsing flow to
make the lexer lazy. This includes the `Lexer`, `TokenSource`, and
`Parser`. For context, the `TokenSource` is a wrapper around the `Lexer`
to filter out the trivia tokens[^1]. Now, the parser will ask the token
source to get the next token and only then the lexer will continue and
emit the token. This means that the lexer needs to be aware of the
"current" token. When the `next_token` is called, the current token will
be updated with the newly lexed token.
The main motivation to make the lexer lazy is to allow re-lexing a token
in a different context. This is going to be really useful to make the
parser error resilience. For example, currently the emitted tokens
remains the same even if the parser can recover from an unclosed
parenthesis. This is important because the lexer emits a
`NonLogicalNewline` in parenthesized context while a normal `Newline` in
non-parenthesized context. This different kinds of newline is also used
to emit the indentation tokens which is important for the parser as it's
used to determine the start and end of a block.
Additionally, this allows us to implement the following functionalities:
1. Checkpoint - rewind infrastructure: The idea here is to create a
checkpoint and continue lexing. At a later point, this checkpoint can be
used to rewind the lexer back to the provided checkpoint.
2. Remove the `SoftKeywordTransformer` and instead use lookahead or
speculative parsing to determine whether a soft keyword is a keyword or
an identifier
3. Remove the `Tok` enum. The `Tok` enum represents the tokens emitted
by the lexer but it contains owned data which makes it expensive to
clone. The new `TokenKind` enum just represents the type of token which
is very cheap.
This brings up a question as to how will the parser get the owned value
which was stored on `Tok`. This will be solved by introducing a new
`TokenValue` enum which only contains a subset of token kinds which has
the owned value. This is stored on the lexer and is requested by the
parser when it wants to process the data. For example:
8196720f80/crates/ruff_python_parser/src/parser/expression.rs (L1260-L1262)
[^1]: Trivia tokens are `NonLogicalNewline` and `Comment`
### Remove `SoftKeywordTransformer`
* https://github.com/astral-sh/ruff/pull/11441
* https://github.com/astral-sh/ruff/pull/11459
* https://github.com/astral-sh/ruff/pull/11442
* https://github.com/astral-sh/ruff/pull/11443
* https://github.com/astral-sh/ruff/pull/11474
For context,
https://github.com/RustPython/RustPython/pull/4519/files#diff-5de40045e78e794aa5ab0b8aacf531aa477daf826d31ca129467703855408220
added support for soft keywords in the parser which uses infinite
lookahead to classify a soft keyword as a keyword or an identifier. This
is a brilliant idea as it basically wraps the existing Lexer and works
on top of it which means that the logic for lexing and re-lexing a soft
keyword remains separate. The change here is to remove
`SoftKeywordTransformer` and let the parser determine this based on
context, lookahead and speculative parsing.
* **Context:** The transformer needs to know the position of the lexer
between it being at a statement position or a simple statement position.
This is because a `match` token starts a compound statement while a
`type` token starts a simple statement. **The parser already knows
this.**
* **Lookahead:** Now that the parser knows the context it can perform
lookahead of up to two tokens to classify the soft keyword. The logic
for this is mentioned in the PR implementing it for `type` and `match
soft keyword.
* **Speculative parsing:** This is where the checkpoint - rewind
infrastructure helps. For `match` soft keyword, there are certain cases
for which we can't classify based on lookahead. The idea here is to
create a checkpoint and keep parsing. Based on whether the parsing was
successful and what tokens are ahead we can classify the remaining
cases. Refer to #11443 for more details.
If the soft keyword is being parsed in an identifier context, it'll be
converted to an identifier and the emitted token will be updated as
well. Refer
8196720f80/crates/ruff_python_parser/src/parser/expression.rs (L487-L491).
The `case` soft keyword doesn't require any special handling because
it'll be a keyword only in the context of a match statement.
### Update the parser API
* https://github.com/astral-sh/ruff/pull/11494
* https://github.com/astral-sh/ruff/pull/11505
Now that the lexer is in sync with the parser, and the parser helps to
determine whether a soft keyword is a keyword or an identifier, the
lexer cannot be used on its own. The reason being that it's not
sensitive to the context (which is correct). This means that the parser
API needs to be updated to not allow any access to the lexer.
Previously, there were multiple ways to parse the source code:
1. Passing the source code itself
2. Or, passing the tokens
Now that the lexer and parser are working together, the API
corresponding to (2) cannot exists. The final API is mentioned in this
PR description: https://github.com/astral-sh/ruff/pull/11494.
### Refactor the downstream tools (linter and formatter)
* https://github.com/astral-sh/ruff/pull/11511
* https://github.com/astral-sh/ruff/pull/11515
* https://github.com/astral-sh/ruff/pull/11529
* https://github.com/astral-sh/ruff/pull/11562
* https://github.com/astral-sh/ruff/pull/11592
And, the final set of changes involves updating all references of the
lexer and `Tok` enum. This was done in two-parts:
1. Update all the references in a way that doesn't require any changes
from this PR i.e., it can be done independently
* https://github.com/astral-sh/ruff/pull/11402
* https://github.com/astral-sh/ruff/pull/11406
* https://github.com/astral-sh/ruff/pull/11418
* https://github.com/astral-sh/ruff/pull/11419
* https://github.com/astral-sh/ruff/pull/11420
* https://github.com/astral-sh/ruff/pull/11424
2. Update all the remaining references to use the changes made in this
PR
For (2), there were various strategies used:
1. Introduce a new `Tokens` struct which wraps the token vector and add
methods to query a certain subset of tokens. These includes:
1. `up_to_first_unknown` which replaces the `tokenize` function
2. `in_range` and `after` which replaces the `lex_starts_at` function
where the former returns the tokens within the given range while the
latter returns all the tokens after the given offset
2. Introduce a new `TokenFlags` which is a set of flags to query certain
information from a token. Currently, this information is only limited to
any string type token but can be expanded to include other information
in the future as needed. https://github.com/astral-sh/ruff/pull/11578
3. Move the `CommentRanges` to the parsed output because this
information is common to both the linter and the formatter. This removes
the need for `tokens_and_ranges` function.
## Test Plan
- [x] Update and verify the test snapshots
- [x] Make sure the entire test suite is passing
- [x] Make sure there are no changes in the ecosystem checks
- [x] Run the fuzzer on the parser
- [x] Run this change on dozens of open-source projects
### Running this change on dozens of open-source projects
Refer to the PR description to get the list of open source projects used
for testing.
Now, the following tests were done between `main` and this branch:
1. Compare the output of `--select=E999` (syntax errors)
2. Compare the output of default rule selection
3. Compare the output of `--select=ALL`
**Conclusion: all output were same**
## What's next?
The next step is to introduce re-lexing logic and update the parser to
feed the recovery information to the lexer so that it can emit the
correct token. This moves us one step closer to having error resilience
in the parser and provides Ruff the possibility to lint even if the
source code contains syntax errors.
## Summary
This moves the string-prefix enumerations in `ruff_python_ast` to a
separate submodule. I think this helps clarify that these prefixes are
purely abstract: they only depend on each other, and do not depend on
any of the other code in `nodes.rs` in any way. Moreover, while various
AST nodes _use_ them, they're not really nodes themselves, so they feel
slightly out of place in `nodes.rs`.
I considered moving all of them to `str.rs`, but it felt like enough
code that it could be a separate submodule.
## Test Plan
`cargo test`
## Summary
This PR renames `AnyStringKind` to `AnyStringFlags` and `AnyStringFlags`
to `AnyStringFlagsInner`.
The main motivation is to have consistent usage of "kind" and "flags".
For each string kind, it's "flags" like `StringLiteralFlags`,
`BytesLiteralFlags`, and `FStringFlags` but it was `AnyStringKind` for
the "any" variant.
(Supersedes #9152, authored by @LaBatata101)
## Summary
This PR replaces the current parser generated from LALRPOP to a
hand-written recursive descent parser.
It also updates the grammar for [PEP
646](https://peps.python.org/pep-0646/) so that the parser outputs the
correct AST. For example, in `data[*x]`, the index expression is now a
tuple with a single starred expression instead of just a starred
expression.
Beyond the performance improvements, the parser is also error resilient
and can provide better error messages. The behavior as seen by any
downstream tools isn't changed. That is, the linter and formatter can
still assume that the parser will _stop_ at the first syntax error. This
will be updated in the following months.
For more details about the change here, refer to the PR corresponding to
the individual commits and the release blog post.
## Test Plan
Write _lots_ and _lots_ of tests for both valid and invalid syntax and
verify the output.
## Acknowledgements
- @MichaReiser for reviewing 100+ parser PRs and continuously providing
guidance throughout the project
- @LaBatata101 for initiating the transition to a hand-written parser in
#9152
- @addisoncrump for implementing the fuzzer which helped
[catch](https://github.com/astral-sh/ruff/pull/10903)
[a](https://github.com/astral-sh/ruff/pull/10910)
[lot](https://github.com/astral-sh/ruff/pull/10966)
[of](https://github.com/astral-sh/ruff/pull/10896)
[bugs](https://github.com/astral-sh/ruff/pull/10877)
---------
Co-authored-by: Victor Hugo Gomes <labatata101@linuxmail.org>
Co-authored-by: Micha Reiser <micha@reiser.io>
## Summary
Given:
```python
F"{"ڤ
```
We try to locate the "unclosed left brace" error by subtracting the
quote size from the lexer offset -- so we subtract 1 from the end of the
source, which puts us in the middle of a Unicode character. I don't
think we should try to adjust the offset in this way, since there can be
content _after_ the quote. For example, with the advent of PEP 701, this
string could reasonably be fixed as:
```python
F"{"ڤ"}"
````
Closes https://github.com/astral-sh/ruff/issues/9379.
## Summary
This helps a bit with (but does not close) the issues described in
https://github.com/astral-sh/ruff/issues/9311. E.g., now, we at least
see: `error: Failed to format main.py: source contains syntax errors:
invalid syntax. Got unexpected token '=' at byte offset 20`.
## Summary
This PR adds some helper structs to the linter paths to enable passing
in the pre-computed tokens and parsed source code during benchmarking,
to remove lexing and parsing from the overall linter benchmark
measurement. We already remove parsing for the formatter, and we have
separate benchmarks for the lexer and the parser, so this should make it
much easier to measure linter performance changes.
## Summary
This PR fixes the bug in the lexer where the `Mode::Ipython` wasn't
being considered when initializing the soft keyword transformer which
wraps the lexer. This means that if the source code starts with either
`match` or `type` keyword, then the keywords were being considered as
name tokens instead. For example,
```python
match foo:
case bar:
pass
```
This would transform the `match` keyword into an identifier if the mode
is `Ipython`.
The fix is to reverse the condition in the soft keyword initializer so
that any new modes are by default considered as the lexer being at start
of line.
## Test Plan
Add a new test case for `Mode::Ipython` and verify the snapshot.
fixes: #8870
Update to [Rust
1.74](https://blog.rust-lang.org/2023/11/16/Rust-1.74.0.html) and use
the new clippy lints table.
The update itself introduced a new clippy lint about superfluous hashes
in raw strings, which got removed.
I moved our lint config from `rustflags` to the newly stabilized
[workspace.lints](https://doc.rust-lang.org/stable/cargo/reference/workspaces.html#the-lints-table).
One consequence is that we have to `unsafe_code = "warn"` instead of
"forbid" because the latter now actually bans unsafe code:
```
error[E0453]: allow(unsafe_code) incompatible with previous forbid
--> crates/ruff_source_file/src/newlines.rs:62:17
|
62 | #[allow(unsafe_code)]
| ^^^^^^^^^^^ overruled by previous forbid
|
= note: `forbid` lint level was set on command line
```
---------
Co-authored-by: Charlie Marsh <charlie.r.marsh@gmail.com>
## Summary
This commit adds some additional error checking to the parser such that
assignments that are invalid syntax are rejected. This covers the
obvious cases like `5 = 3` and some not so obvious cases like `x + y =
42`.
This does add an additional recursive call to the parser for the cases
handling assignments. I had initially been concerned about doing this,
but `set_context` is already doing recursion during assignments, so I
didn't feel as though this was changing any fundamental performance
characteristics of the parser. (Also, in practice, I would expect any
such recursion here to be quite shallow since the recursion is done on
the target of an assignment. Such things are rarely nested much in
practice.)
Fixes#6895
## Test Plan
I've added unit tests covering every case that is detected as invalid on
an `Expr`.
## Summary
This PR fixes a bug in the lexer for f-string format spec where it would
consider the `{{` (double curly braces) as an escape pattern.
This is not the case as evident by the
[PEP](https://peps.python.org/pep-0701/#how-to-produce-these-new-tokens)
as well but I missed the part:
> [..]
> * **If in “format specifier mode” (see step 3), an opening brace ({)
or a closing brace (}).**
> * If not in “format specifier mode” (see step 3), an opening brace ({)
or a closing brace (}) that is not immediately followed by another
opening/closing brace.
## Test Plan
Add a test case to verify the fix and update the snapshot.
fixes: #7778
## Summary
This PR fixes a bug where if a Windows newline (`\r\n`) character was
escaped, then only the `\r` was consumed and not `\n` leading to an
unterminated string error.
## Test Plan
Add new test cases to check the newline escapes.
fixes: #7632
## Summary
When lexing a number like `0x995DC9BBDF1939FA` that exceeds our small
number representation, we were only storing the portion after the base
(in this case, `995DC9BBDF1939FA`). When using that representation in
code generation, this could lead to invalid syntax, since
`995DC9BBDF1939FA)` on its own is not a valid integer.
This PR modifies the code to store the full span, including the radix
prefix.
See:
https://github.com/astral-sh/ruff/issues/7455#issuecomment-1739802958.
## Test Plan
`cargo test`
## Summary
This is a follow-up to #7469 that attempts to achieve similar gains, but
without introducing malachite. Instead, this PR removes the `BigInt`
type altogether, instead opting for a simple enum that allows us to
store small integers directly and only allocate for values greater than
`i64`:
```rust
/// A Python integer literal. Represents both small (fits in an `i64`) and large integers.
#[derive(Clone, PartialEq, Eq, Hash)]
pub struct Int(Number);
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub enum Number {
/// A "small" number that can be represented as an `i64`.
Small(i64),
/// A "large" number that cannot be represented as an `i64`.
Big(Box<str>),
}
impl std::fmt::Display for Number {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
Number::Small(value) => write!(f, "{value}"),
Number::Big(value) => write!(f, "{value}"),
}
}
}
```
We typically don't care about numbers greater than `isize` -- our only
uses are comparisons against small constants (like `1`, `2`, `3`, etc.),
so there's no real loss of information, except in one or two rules where
we're now a little more conservative (with the worst-case being that we
don't flag, e.g., an `itertools.pairwise` that uses an extremely large
value for the slice start constant). For simplicity, a few diagnostics
now show a dedicated message when they see integers that are out of the
supported range (e.g., `outdated-version-block`).
An additional benefit here is that we get to remove a few dependencies,
especially `num-bigint`.
## Test Plan
`cargo test`
