Commit Graph

267 Commits

Author SHA1 Message Date
Dhruv Manilawala 5b81b8368d
Make associativity a property of operator precedence (#11065)
## Summary

This PR does a few things but the main change is that is makes
associativity a property of operator precedence.

1. Rename `Precedence` -> `OperatorPrecedence`
2. Rename `parse_expression_with_precedence` ->
`parse_binary_expression_or_higher`
3. Move `current_binding_power` to `OperatorPrecedence::try_from_tokens`
[^1]
4. Add a `OperatorPrecedence::is_right_associative` method
5. Move from `increment_precedence` to using `<=` / `<` to check if the
parsing loop needs to stop [^2]

[^1]: Another alternative would be to have two separate methods to avoid
lookahead as it's required only for once case (`not in`). So,
`try_from_current_token(current).or_else(|| try_from_next_token(current,
peek))`
[^2]: This will allow us to easily make the refactors mentioned in
#10752

## Test Plan

Make sure the precedence parsing algorithm is still correct by running
the test suite, fuzz testing it and running it against a dozen or so
open-source repositories.
2024-04-23 04:28:46 +00:00
Dhruv Manilawala c30735d4a7
Add `ExpressionContext` for expression parsing (#11055)
## Summary

This PR adds a new `ExpressionContext` struct which is used in
expression parsing.

This solves the following problem:
1. Allowing starred expression with different precedence
2. Allowing yield expression in certain context
3. Remove ambiguity with `in` keyword when parsing a `for ... in`
statement

For context, (1) was solved by adding `parse_star_expression_list` and
`parse_star_expression_or_higher` in #10623, (2) was solved by by adding
`parse_yield_expression_or_else` in #10809, and (3) was fixed in #11009.
All of the mentioned functions have been removed in favor of the context
flags.

As mentioned in #11009, an ideal solution would be to implement an
expression context which is what this PR implements. This is passed
around as function parameter and the call stack is used to automatically
reset the context.

### Recovery

How should the parser recover if the target expression is invalid when
an expression can consume the `in` keyword?

1. Should the `in` keyword be part of the target expression?
2. Or, should the expression parsing stop as soon as `in` keyword is
encountered, no matter the expression?

For example:
```python
for yield x in y: ...

# Here, should this be parsed as
for (yield x) in (y): ...
# Or
for (yield x in y): ...
# where the `in iter` part is missing
```

Or, for binary expression parsing:
```python
for x or y in z: ...

# Should this be parsed as
for (x or y) in z: ...
# Or
for (x or y in z): ...
# where the `in iter` part is missing
```

This need not be solved now, but is very easy to change. For context
this PR does the following:
* For binary, comparison, and unary expressions, stop at `in`
* For lambda, yield expressions, consume the `in`

## Test Plan

1. Add test cases for the `for ... in` statement and verify the
snapshots
2. Make sure the existing test suite pass
3. Run the fuzzer for around 3000 generated source code
4. Run the updated logic on a dozen or so open source repositories
(codename "parser-checkouts")
2024-04-23 04:19:05 +00:00
Carl Meyer c80b9a4a90
Reduce size of Stmt from 144 to 120 bytes (#11051)
## Summary

I happened to notice that we box `TypeParams` on `StmtClassDef` but not
on `StmtFunctionDef` and wondered why, since `StmtFunctionDef` is bigger
and sets the size of `Stmt`.

@charliermarsh found that at the time we started boxing type params on
classes, classes were the largest statement type (see #6275), but that's
no longer true.

So boxing type-params also on functions reduces the overall size of
`Stmt`.

## Test Plan

The `<=` size tests are a bit irritating (since their failure doesn't
tell you the actual size), but I manually confirmed that the size is
actually 120 now.
2024-04-19 17:02:17 -06:00
Dhruv Manilawala d3cd61f804
Use empty range when there's "gap" in token source (#11032)
## Summary

This fixes a bug where the parser would panic when there is a "gap" in
the token source.

What's a gap?

The reason it's `<=` instead of just `==` is because there could be
whitespaces between
the two tokens. For example:

```python
#     last token end
#     | current token (newline) start
#     v v
def foo \n
#      ^
#      assume there's trailing whitespace here
```

Or, there could tokens that are considered "trivia" and thus aren't
emitted by the token
source. These are comments and non-logical newlines. For example:

```python
#     last token end
#     v
def foo # comment\n
#                ^ current token (newline) start
```

In either of the above cases, there's a "gap" between the end of the
last token and start
of the current token.

## Test Plan

Add test cases and update the snapshots.
2024-04-19 11:36:26 +00:00
Dhruv Manilawala 9bb23b0a38
Expect indented case block instead of match stmt (#11033)
## Summary

This PR adds a new `Clause::Case` and uses it to parse the body of a
`case` block. Earlier, it was using `Match` which would give an
incorrect error message like:

```
  |
1 | match subject:
2 |     case 1:
3 |     case 2: ...
  |     ^^^^ Syntax Error: Expected an indented block after `match` statement
  |
```

## Test Plan

Add test case and update the snapshot.
2024-04-19 16:46:15 +05:30
Dhruv Manilawala b7066e64e7
Consider binary expr for parenthesized with items parsing (#11012)
## Summary

This PR fixes the bug in with items parsing where it would fail to
recognize that the parenthesized expression is part of a large binary
expression.

## Test Plan

Add test cases and verified the snapshots.
2024-04-18 21:39:30 +05:30
Dhruv Manilawala 6c4d779140
Consider `if` expression for parenthesized with items parsing (#11010)
## Summary

This PR fixes the bug in parenthesized with items parsing where the `if`
expression would result into a syntax error.

The reason being that once we identify that the ambiguous left
parenthesis belongs to the context expression, the parser converts the
parsed with item into an equivalent expression. Then, the parser
continuous to parse any postfix expressions. Now, attribute, subscript,
and call are taken into account as they're grouped in
`parse_postfix_expression` but `if` expression has it's own parsing
function.

Use `parse_if_expression` once all postfix expressions have been parsed.
Ideally, I think that `if` could be included in postfix expression
parsing as they can be chained as well (`x if True else y if True else
z`).

## Test Plan

Add test cases and verified the snapshots.
2024-04-18 14:30:15 +00:00
Dhruv Manilawala 8020d486f6
Reset `FOR_TARGET` context for all kinds of parentheses (#11009)
## Summary

This PR fixes a bug in the new parser which involves the parser context
w.r.t. for statement. This is specifically around the `in` keyword which
can be present in the target expression and shouldn't be considered to
be part of the `for` statement header. Ideally it should use a context
which is passed between functions, thus using a call stack to set /
unset a specific variant which will be done in a follow-up PR as it
requires some amount of refactor.

## Test Plan

Add test cases and update the snapshots.
2024-04-18 19:37:50 +05:30
Dhruv Manilawala 13ffb5bc19
Replace LALRPOP parser with hand-written parser (#10036)
(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>
2024-04-18 17:57:39 +05:30
Boshen d467aa78c2
Remove an unused dependency (#10747)
## Summary

Continuation of #10475, I improved [`cargo
shear`](https://github.com/Boshen/cargo-shear) even more.

We can put this in CI once I test it a bit more, given that [ignoring
false
positives](https://github.com/Boshen/cargo-shear?tab=readme-ov-file#ignore-false-positives)
has been implemented.

## Test Plan

`cargo check --all-features --all-targets`
2024-04-03 09:57:19 +01:00
veryyet c5ea4209bb
chore: remove repetitive words (#10502) 2024-03-21 03:57:16 +00:00
Alex Waygood 7caf0d064a
Simplify formatting of strings by using flags from the AST nodes (#10489) 2024-03-20 16:16:54 +00:00
Alex Waygood ffd6e79677
Fix typo in `string_token_flags.rs` (#10476) 2024-03-19 17:43:08 +00:00
Alex Waygood 162d2eb723
Track casing of r-string prefixes in the tokenizer and AST (#10314)
Co-authored-by: Micha Reiser <micha@reiser.io>
2024-03-18 17:18:04 +00:00
Alex Waygood 92e6026446
Apply NFKC normalization to unicode identifiers in the lexer (#10412) 2024-03-18 11:56:56 +00:00
Alex Waygood c2e15f38ee
Unify enums used for internal representation of quoting style (#10383) 2024-03-13 17:19:17 +00:00
Auguste Lalande 3ed707f245
Spellcheck & grammar (#10375)
## Summary

I used `codespell` and `gramma` to identify mispellings and grammar
errors throughout the codebase and fixed them. I tried not to make any
controversial changes, but feel free to revert as you see fit.
2024-03-13 02:34:23 +00:00
Gautier Moin a067d87ccc
Fix incorrect `Parameter` range for `*args` and `**kwargs` (#10283)
## Summary

Fix #10282 

This PR updates the Python grammar to include the `*` character in
`*args` `**kwargs` in the range of the `Parameter`
```
def f(*args, **kwargs): pass
#      ~~~~    ~~~~~~    <-- range before the PR
#     ^^^^^  ^^^^^^^^    <-- range after
```

The invalid syntax `def f(*, **kwargs): ...` is also now correctly
reported.

## Test Plan

Test cases were added to `function.rs`.
2024-03-08 18:57:49 -05:00
Alex Waygood 1d97f27335
Start tracking quoting style in the AST (#10298)
This PR modifies our AST so that nodes for string literals, bytes literals and f-strings all retain the following information:
- The quoting style used (double or single quotes)
- Whether the string is triple-quoted or not
- Whether the string is raw or not

This PR is a followup to #10256. Like with that PR, this PR does not, in itself, fix any bugs. However, it means that we will have the necessary information to preserve quoting style and rawness of strings in the `ExprGenerator` in a followup PR, which will allow us to provide a fix for https://github.com/astral-sh/ruff/issues/7799.

The information is recorded on the AST nodes using a bitflag field on each node, similarly to how we recorded the information on `Tok::String`, `Tok::FStringStart` and `Tok::FStringMiddle` tokens in #10298. Rather than reusing the bitflag I used for the tokens, however, I decided to create a custom bitflag for each AST node.

Using different bitflags for each node allows us to make invalid states unrepresentable: it is valid to set a `u` prefix on a string literal, but not on a bytes literal or an f-string. It also allows us to have better debug representations for each AST node modified in this PR.
2024-03-08 19:11:47 +00:00
Alex Waygood c504d7ab11
Track quoting style in the tokenizer (#10256) 2024-03-08 08:40:06 +00:00
Micha Reiser 184241f99a
Remove `Expr` postfix from `ExprNamed`, `ExprIf`, and `ExprGenerator` (#10229)
The expression types in our AST are called `ExprYield`, `ExprAwait`,
`ExprStringLiteral` etc, except `ExprNamedExpr`, `ExprIfExpr` and
`ExprGenratorExpr`. This seems to align with [Python AST's
naming](https://docs.python.org/3/library/ast.html) but feels
inconsistent and excessive.

This PR removes the `Expr` postfix from `ExprNamedExpr`, `ExprIfExpr`,
and `ExprGeneratorExpr`.
2024-03-04 12:55:01 +01:00
Micha Reiser 77c5561646
Add `parenthesized` flag to `ExprTuple` and `ExprGenerator` (#9614) 2024-02-26 15:35:20 +00:00
Dhruv Manilawala 33ac2867b7
Use non-parenthesized range for `DebugText` (#9953)
## Summary

This PR fixes the `DebugText` implementation to use the expression range
instead of the parenthesized range.

Taking the following code snippet as an example:
```python
x = 1
print(f"{  ( x  ) = }")
```

The output of running it would be:
```
  ( x  ) = 1
```

Notice that the whitespace between the parentheses and the expression is
preserved as is.

Currently, we don't preserve this information in the AST which defeats
the purpose of `DebugText` as the main purpose of the struct is to
preserve whitespaces _around_ the expression.

This is also problematic when generating the code from the AST node as
then the generator has no information about the parentheses the
whitespaces between them and the expression which would lead to the
removal of the parentheses in the generated code.

I noticed this while working on the f-string formatting where the debug
text would be used to preserve the text surrounding the expression in
the presence of debug expression. The parentheses were being dropped
then which made me realize that the problem is instead in the parser.

## Test Plan

1. Add a test case for the parser
2. Add a test case for the generator
2024-02-12 23:00:02 +05:30
Charlie Marsh 6f0e4ad332
Remove unnecessary string cloning from the parser (#9884)
Closes https://github.com/astral-sh/ruff/issues/9869.
2024-02-09 16:03:27 -05:00
Charlie Marsh 49fe1b85f2
Reduce size of `Expr` from 80 to 64 bytes (#9900)
## Summary

This PR reduces the size of `Expr` from 80 to 64 bytes, by reducing the
sizes of...

- `ExprCall` from 72 to 56 bytes, by using boxed slices for `Arguments`.
- `ExprCompare` from 64 to 48 bytes, by using boxed slices for its
various vectors.

In testing, the parser gets a bit faster, and the linter benchmarks
improve quite a bit.
2024-02-09 02:53:13 +00:00
Micha Reiser fe7d965334
Reduce `Result<Tok, LexicalError>` size by using `Box<str>` instead of `String` (#9885) 2024-02-08 20:36:22 +00:00
Micha Reiser 688177ff6a
Use Rust 1.76 (#9897) 2024-02-08 18:20:08 +00:00
Charlie Marsh 6fffde72e7
Use `memchr` for string lexing (#9888)
## Summary

On `main`, string lexing consists of walking through the string
character-by-character to search for the closing quote (with some
nuance: we also need to skip escaped characters, and error if we see
newlines in non-triple-quoted strings). This PR rewrites `lex_string` to
instead use `memchr` to search for the closing quote, which is
significantly faster. On my machine, at least, the `globals.py`
benchmark (which contains a lot of docstrings) gets 40% faster...

```text
lexer/numpy/globals.py  time:   [3.6410 µs 3.6496 µs 3.6585 µs]
                        thrpt:  [806.53 MiB/s 808.49 MiB/s 810.41 MiB/s]
                 change:
                        time:   [-40.413% -40.185% -39.984%] (p = 0.00 < 0.05)
                        thrpt:  [+66.623% +67.181% +67.822%]
                        Performance has improved.
Found 2 outliers among 100 measurements (2.00%)
  2 (2.00%) high mild
lexer/unicode/pypinyin.py
                        time:   [12.422 µs 12.445 µs 12.467 µs]
                        thrpt:  [337.03 MiB/s 337.65 MiB/s 338.27 MiB/s]
                 change:
                        time:   [-9.4213% -9.1930% -8.9586%] (p = 0.00 < 0.05)
                        thrpt:  [+9.8401% +10.124% +10.401%]
                        Performance has improved.
Found 3 outliers among 100 measurements (3.00%)
  1 (1.00%) high mild
  2 (2.00%) high severe
lexer/pydantic/types.py time:   [107.45 µs 107.50 µs 107.56 µs]
                        thrpt:  [237.11 MiB/s 237.24 MiB/s 237.35 MiB/s]
                 change:
                        time:   [-4.0108% -3.7005% -3.3787%] (p = 0.00 < 0.05)
                        thrpt:  [+3.4968% +3.8427% +4.1784%]
                        Performance has improved.
Found 7 outliers among 100 measurements (7.00%)
  2 (2.00%) high mild
  5 (5.00%) high severe
lexer/numpy/ctypeslib.py
                        time:   [46.123 µs 46.165 µs 46.208 µs]
                        thrpt:  [360.36 MiB/s 360.69 MiB/s 361.01 MiB/s]
                 change:
                        time:   [-19.313% -18.996% -18.710%] (p = 0.00 < 0.05)
                        thrpt:  [+23.016% +23.451% +23.935%]
                        Performance has improved.
Found 8 outliers among 100 measurements (8.00%)
  3 (3.00%) low mild
  1 (1.00%) high mild
  4 (4.00%) high severe
lexer/large/dataset.py  time:   [231.07 µs 231.19 µs 231.33 µs]
                        thrpt:  [175.87 MiB/s 175.97 MiB/s 176.06 MiB/s]
                 change:
                        time:   [-2.0437% -1.7663% -1.4922%] (p = 0.00 < 0.05)
                        thrpt:  [+1.5148% +1.7981% +2.0864%]
                        Performance has improved.
Found 10 outliers among 100 measurements (10.00%)
  5 (5.00%) high mild
  5 (5.00%) high severe
```
2024-02-08 17:23:06 +00:00
Seo Sanghyeon df7fb95cbc
Index multiline f-strings (#9837)
Fix #9777.
2024-02-05 21:25:33 -05:00
Micha Reiser 47ad7b4500
Approximate tokens len (#9546) 2024-01-19 17:39:37 +01:00
Micha Reiser 21f2d0c90b
Add an explicit fast path for whitespace to `is_identifier_continuation` (#9532) 2024-01-16 08:23:43 +00:00
Micha Reiser f192c72596
Remove type parameter from `parse_*` methods (#9466) 2024-01-11 19:41:19 +01:00
Micha Reiser 94968fedd5
Use Rust 1.75 toolchain (#9437) 2024-01-08 18:03:16 +01:00
Micha Reiser b1a5df8694
Move `locate_cmp_ops` to `invalid_literal_comparisons` (#9438) 2024-01-08 13:15:36 +01:00
Charlie Marsh 1666c7a5cb
Add size hints to string parser (#9413) 2024-01-06 15:59:34 -05:00
Charlie Marsh f0d43dafcf
Ignore trailing quotes for unclosed l-brace errors (#9388)
## 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.
2024-01-04 05:00:55 +00:00
Charlie Marsh 9073220887
Make all dependencies workspace dependencies (#9333)
## Summary

This PR modifies our `Cargo.toml` files to use workspace dependencies
for _all_ dependencies, rather than the status quo of sporadically
trying to use workspace dependencies for those dependencies that are
used across multiple crates. I find the current situation more confusing
and harder to manage, since we have a mix of workspace and crate-local
dependencies, whereas this setup consistently uses the same approach for
all dependencies.
2024-01-02 13:41:59 +00:00
Charlie Marsh 48e04cc2c8
Add row and column numbers to formatted parse errors (#9321)
## Summary

We now render parse errors in the formatter identically to those in the
linter, e.g.:

```
❯ cargo run -p ruff_cli -- format foo.py
error: Failed to parse foo.py:1:17: Unexpected token '='
```

Closes https://github.com/astral-sh/ruff/issues/8338.

Closes https://github.com/astral-sh/ruff/issues/9311.
2023-12-31 07:10:45 -05:00
Charlie Marsh e80260a3c5
Remove source path from parser errors (#9322)
## Summary

I always found it odd that we had to pass this in, since it's really
higher-level context for the error. The awkwardness is further evidenced
by the fact that we pass in fake values everywhere (even outside of
tests). The source path isn't actually used to display the error; it's
only accessed elsewhere to _re-display_ the error in certain cases. This
PR modifies to instead pass the path directly in those cases.
2023-12-30 20:33:05 +00:00
Charlie Marsh 97e9d3c54f
Use `Display` for formatter parse errors (#9316)
## 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`.
2023-12-29 22:26:57 +00:00
Charlie Marsh 9d6444138b
Remove lexing and parsing from the linter benchmark (#9264)
## 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.
2023-12-23 16:43:11 -05:00
Andrew Gallant 3ce145c476
release: switch to Cargo's default (#9031)
This sets `lto = "thin"` instead of using "fat" LTO, and sets
`codegen-units = 16`. These are the defaults for Cargo's `release`
profile, and I think it may give us faster iteration times, especially
when benchmarking. The point of this PR is to see what kind of impact
this has on benchmarks. It is expected that benchmarks may regress to
some extent.

I did some quick ad hoc experiments to quantify this change in compile
times. Namely, I ran:

    cargo build --profile release -p ruff_cli

Then I ran

touch crates/ruff_python_formatter/src/expression/string/docstring.rs

(because that's where i've been working lately) and re-ran

    cargo build --profile release -p ruff_cli

This last command is what I timed, since it reflects how much time one
has to wait between making a change and getting a compiled artifact.

Here are my results:

* With status quo `release` profile, build takes 77s
* with `release` but `lto = "thin"`, build takes 41s
* with `release`, but `lto = false`, build takes 19s
* with `release`, but `lto = false` **and** `codegen-units = 16`, build
takes 7s
* with `release`, but `lto = "thin"` **and** `codegen-units = 16`, build
takes 16s (i believe this is the default `release` configuration)

This PR represents the last option. It's not the fastest to compile, but
it's nearly a whole minute faster! The idea is that with `codegen-units
= 16`, we still make use of parallelism, but keep _some_ level of LTO on
to try and re-gain what we lose by increasing the number of codegen
units.
2023-12-15 08:19:35 -05:00
Dhruv Manilawala cdac90ef68
New AST nodes for f-string elements (#8835)
Rebase of #6365 authored by @davidszotten.

## Summary

This PR updates the AST structure for an f-string elements.

The main **motivation** behind this change is to have a dedicated node
for the string part of an f-string. Previously, the existing
`ExprStringLiteral` node was used for this purpose which isn't exactly
correct. The `ExprStringLiteral` node should include the quotes as well
in the range but the f-string literal element doesn't include the quote
as it's a specific part within an f-string. For example,

```python
f"foo {x}"
# ^^^^
# This is the literal part of an f-string
```

The introduction of `FStringElement` enum is helpful which represent
either the literal part or the expression part of an f-string.

### Rule Updates

This means that there'll be two nodes representing a string depending on
the context. One for a normal string literal while the other is a string
literal within an f-string. The AST checker is updated to accommodate
this change. The rules which work on string literal are updated to check
on the literal part of f-string as well.

#### Notes

1. The `Expr::is_literal_expr` method would check for
`ExprStringLiteral` and return true if so. But now that we don't
represent the literal part of an f-string using that node, this improves
the method's behavior and confines to the actual expression. We do have
the `FStringElement::is_literal` method.
2. We avoid checking if we're in a f-string context before adding to
`string_type_definitions` because the f-string literal is now a
dedicated node and not part of `Expr`.
3. Annotations cannot use f-string so we avoid changing any rules which
work on annotation and checks for `ExprStringLiteral`.

## Test Plan

- All references of `Expr::StringLiteral` were checked to see if any of
the rules require updating to account for the f-string literal element
node.
- New test cases are added for rules which check against the literal
part of an f-string.
- Check the ecosystem results and ensure it remains unchanged.

## Performance

There's a performance penalty in the parser. The reason for this remains
unknown as it seems that the generated assembly code is now different
for the `__reduce154` function. The reduce function body is just popping
the `ParenthesizedExpr` on top of the stack and pushing it with the new
location.

- The size of `FStringElement` enum is the same as `Expr` which is what
it replaces in `FString::format_spec`
- The size of `FStringExpressionElement` is the same as
`ExprFormattedValue` which is what it replaces

I tried reducing the `Expr` enum from 80 bytes to 72 bytes but it hardly
resulted in any performance gain. The difference can be seen here:
- Original profile: https://share.firefox.dev/3Taa7ES
- Profile after boxing some node fields:
https://share.firefox.dev/3GsNXpD

### Backtracking

I tried backtracking the changes to see if any of the isolated change
produced this regression. The problem here is that the overall change is
so small that there's only a single checkpoint where I can backtrack and
that checkpoint results in the same regression. This checkpoint is to
revert using `Expr` to the `FString::format_spec` field. After this
point, the change would revert back to the original implementation.

## Review process

The review process is similar to #7927. The first set of commits update
the node structure, parser, and related AST files. Then, further commits
update the linter and formatter part to account for the AST change.

---------

Co-authored-by: David Szotten <davidszotten@gmail.com>
2023-12-07 10:28:05 -06:00
Micha Reiser 7e390d3772
Move `ParenthesizedExpr` to `ruff_python_parser` (#8987) 2023-12-04 05:36:28 +00:00
Charlie Marsh 20782ab02c
Support type alias statements in simple statement positions (#8916)
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## Summary

Our `SoftKeywordTokenizer` only respected soft keywords in compound
statement positions -- for example, at the start of a logical line:

```python
type X = int
```

However, type aliases can also appear in simple statement positions,
like:

```python
class Class: type X = int
```

(Note that `match` and `case` are _not_ valid keywords in such
positions.)

This PR upgrades the tokenizer to track both kinds of valid positions.

Closes https://github.com/astral-sh/ruff/issues/8900.
Closes https://github.com/astral-sh/ruff/issues/8899.

## Test Plan

`cargo test`
2023-11-30 19:15:19 +00:00
Charlie Marsh 774c77adae
Avoid off-by-one error in with-item named expressions (#8915)
## Summary

Given `with (a := b): pass`, we truncate the `WithItem` range by one on
both sides such that the parentheses are part of the statement, rather
than the item. However, for `with (a := b) as x: pass`, we want to avoid
this trick.

Closes https://github.com/astral-sh/ruff/issues/8913.
2023-11-30 00:11:04 +00:00
Charlie Marsh 6435e4e4aa
Enable auto-return-type involving `Optional` and `Union` annotations (#8885)
## Summary

Previously, this was only supported for Python 3.10 and later, since we
always use the PEP 604-style unions.
2023-11-28 18:35:55 -08:00
Dhruv Manilawala 47d80f29a7
Lexer start of line is false only for `Mode::Expression` (#8880)
## 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
2023-11-28 20:38:25 +00:00
Andrew Gallant f585e3e2dc
remove several uses of `unsafe` (#8600)
This PR removes several uses of `unsafe`. I generally limited myself to
low hanging fruit that I could see. There are still a few remaining uses
of `unsafe` that looked a bit more difficult to remove (if possible at
all). But this gets rid of a good chunk of them.

I put each `unsafe` removal into its own commit with a justification for
why I did it. So I would encourage reviewing this PR commit-by-commit.
That way, we can legislate them independently. It's no problem to drop a
commit if we feel the `unsafe` should stay in that case.
2023-11-28 09:50:03 -05:00
Dhruv Manilawala 017e829115
Update string nodes for implicit concatenation (#7927)
## Summary

This PR updates the string nodes (`ExprStringLiteral`,
`ExprBytesLiteral`, and `ExprFString`) to account for implicit string
concatenation.

### Motivation

In Python, implicit string concatenation are joined while parsing
because the interpreter doesn't require the information for each part.
While that's feasible for an interpreter, it falls short for a static
analysis tool where having such information is more useful. Currently,
various parts of the code uses the lexer to get the individual string
parts.

One of the main challenge this solves is that of string formatting.
Currently, the formatter relies on the lexer to get the individual
string parts, and formats them including the comments accordingly. But,
with PEP 701, f-string can also contain comments. Without this change,
it becomes very difficult to add support for f-string formatting.

### Implementation

The initial proposal was made in this discussion:
https://github.com/astral-sh/ruff/discussions/6183#discussioncomment-6591993.
There were various AST designs which were explored for this task which
are available in the linked internal document[^1].

The selected variant was the one where the nodes were kept as it is
except that the `implicit_concatenated` field was removed and instead a
new struct was added to the `Expr*` struct. This would be a private
struct would contain the actual implementation of how the AST is
designed for both single and implicitly concatenated strings.

This implementation is achieved through an enum with two variants:
`Single` and `Concatenated` to avoid allocating a vector even for single
strings. There are various public methods available on the value struct
to query certain information regarding the node.

The nodes are structured in the following way:

```
ExprStringLiteral - "foo" "bar"
|- StringLiteral - "foo"
|- StringLiteral - "bar"

ExprBytesLiteral - b"foo" b"bar"
|- BytesLiteral - b"foo"
|- BytesLiteral - b"bar"

ExprFString - "foo" f"bar {x}"
|- FStringPart::Literal - "foo"
|- FStringPart::FString - f"bar {x}"
  |- StringLiteral - "bar "
  |- FormattedValue - "x"
```

[^1]: Internal document:
https://www.notion.so/astral-sh/Implicit-String-Concatenation-e036345dc48943f89e416c087bf6f6d9?pvs=4

#### Visitor

The way the nodes are structured is that the entire string, including
all the parts that are implicitly concatenation, is a single node
containing individual nodes for the parts. The previous section has a
representation of that tree for all the string nodes. This means that
new visitor methods are added to visit the individual parts of string,
bytes, and f-strings for `Visitor`, `PreorderVisitor`, and
`Transformer`.

## Test Plan

- `cargo insta test --workspace --all-features --unreferenced reject`
- Verify that the ecosystem results are unchanged
2023-11-24 17:55:41 -06:00
konsti 14e65afdc6
Update to Rust 1.74 and use new clippy lints table (#8722)
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>
2023-11-16 18:12:46 -05:00
Andrew Gallant 6a1fa4778f
Reject more syntactically invalid Python programs (#8524)
## 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`.
2023-11-07 07:16:06 -05:00
konsti daea870c3c
Fix panic with 8 in octal escape (#8356)
**Summary** The digits for an octal escape are 0 to 7, not 0 to 8,
fixing the panic in #8355

**Test plan** Regression test parser fixture
2023-10-30 14:42:15 +01:00
Dhruv Manilawala 230c9ce236
Split `Constant` to individual literal nodes (#8064)
## Summary

This PR splits the `Constant` enum as individual literal nodes. It
introduces the following new nodes for each variant:
* `ExprStringLiteral`
* `ExprBytesLiteral`
* `ExprNumberLiteral`
* `ExprBooleanLiteral`
* `ExprNoneLiteral`
* `ExprEllipsisLiteral`

The main motivation behind this refactor is to introduce the new AST
node for implicit string concatenation in the coming PR. The elements of
that node will be either a string literal, bytes literal or a f-string
which can be implemented using an enum. This means that a string or
bytes literal cannot be represented by `Constant::Str` /
`Constant::Bytes` which creates an inconsistency.

This PR avoids that inconsistency by splitting the constant nodes into
it's own literal nodes, literal being the more appropriate naming
convention from a static analysis tool perspective.

This also makes working with literals in the linter and formatter much
more ergonomic like, for example, if one would want to check if this is
a string literal, it can be done easily using
`Expr::is_string_literal_expr` or matching against `Expr::StringLiteral`
as oppose to matching against the `ExprConstant` and enum `Constant`. A
few AST helper methods can be simplified as well which will be done in a
follow-up PR.

This introduces a new `Expr::is_literal_expr` method which is the same
as `Expr::is_constant_expr`. There are also intermediary changes related
to implicit string concatenation which are quiet less. This is done so
as to avoid having a huge PR which this already is.

## Test Plan

1. Verify and update all of the existing snapshots (parser, visitor)
2. Verify that the ecosystem check output remains **unchanged** for both
the linter and formatter

### Formatter ecosystem check

#### `main`

| project | similarity index | total files | changed files |

|----------------|------------------:|------------------:|------------------:|
| cpython | 0.75803 | 1799 | 1647 |
| django | 0.99983 | 2772 | 34 |
| home-assistant | 0.99953 | 10596 | 186 |
| poetry | 0.99891 | 317 | 17 |
| transformers | 0.99966 | 2657 | 330 |
| twine | 1.00000 | 33 | 0 |
| typeshed | 0.99978 | 3669 | 20 |
| warehouse | 0.99977 | 654 | 13 |
| zulip | 0.99970 | 1459 | 22 |

#### `dhruv/constant-to-literal`

| project | similarity index | total files | changed files |

|----------------|------------------:|------------------:|------------------:|
| cpython | 0.75803 | 1799 | 1647 |
| django | 0.99983 | 2772 | 34 |
| home-assistant | 0.99953 | 10596 | 186 |
| poetry | 0.99891 | 317 | 17 |
| transformers | 0.99966 | 2657 | 330 |
| twine | 1.00000 | 33 | 0 |
| typeshed | 0.99978 | 3669 | 20 |
| warehouse | 0.99977 | 654 | 13 |
| zulip | 0.99970 | 1459 | 22 |
2023-10-30 12:13:23 +05:30
Dhruv Manilawala 78bbf6d403
New `Singleton` enum for `PatternMatchSingleton` node (#8063)
## Summary

This PR adds a new `Singleton` enum for the `PatternMatchSingleton`
node.

Earlier the node was using the `Constant` enum but the value for this
pattern can only be either `None`, `True` or `False`. With the coming PR
to remove the `Constant`, this node required a new type to fill in.

This also has the benefit of narrowing the type down to only the
possible values for the node as evident by the removal of `unreachable`.

## Test Plan

Update the AST snapshots and run `cargo test`.
2023-10-30 05:48:53 +00:00
Carter Snook 2f5734d1ac
perf(parser): use faster string parser methods (#8227)
## Summary

This makes use of memchr and other methods to parse the strings
(hopefully) faster. It might also be worth converting the
`parse_fstring_middle` helper to use similar techniques, but I did not
implement it in this PR.

## Test Plan

This was tested using the existing tests and passed all of them.
2023-10-28 18:50:54 -04:00
Carter Snook e2b5c6ac5f
perf(parser): use memchr for lexing comments (#8193) 2023-10-27 02:07:43 +01:00
Charlie Marsh d6a4283003
Fix range of unparenthesized tuple subject in match statement (#8101)
## Summary

This was just a bug in the parser ranges, probably since it was
initially implemented. Given `match n % 3, n % 5: ...`, the "subject"
(i.e., the tuple of two binary operators) was using the entire range of
the `match` statement.

Closes https://github.com/astral-sh/ruff/issues/8091.

## Test Plan

`cargo test`
2023-10-22 19:58:33 -04:00
Dhruv Manilawala 43883b7a15
Disallow f-strings in match pattern literal (#7857)
## Summary

This PR fixes a bug to disallow f-strings in match pattern literal.

```
literal_pattern ::=  signed_number
                     | signed_number "+" NUMBER
                     | signed_number "-" NUMBER
                     | strings
                     | "None"
                     | "True"
                     | "False"
                     | signed_number: NUMBER | "-" NUMBER
```

Source:
https://docs.python.org/3/reference/compound_stmts.html#grammar-token-python-grammar-literal_pattern

Also,

```console
$ python /tmp/t.py
  File "/tmp/t.py", line 4
    case "hello " f"{name}":
         ^^^^^^^^^^^^^^^^^^
SyntaxError: patterns may only match literals and attribute lookups
```

## Test Plan

Update existing test case and accordingly the snapshots. Also, add a new
test case to verify that the parser does raise an error.
2023-10-09 10:11:08 +00:00
Dhruv Manilawala 709abd534a
Fix lexing single-quoted f-string with multi-line format spec (#7787)
## Summary

Reported at https://github.com/python/cpython/issues/110259

## Test Plan

Add test cases for the fix and update the snapshots
2023-10-05 23:12:09 +05:30
Dhruv Manilawala 17fba99ed4
Report precise location for invalid conversion flag (#7809)
## Summary

This PR updates the parser definition to use the precise location when reporting
an invalid f-string conversion flag error.

Taking the following example code:
```python
f"{foo!x}"
```

On earlier version,
```
Error: f-string: invalid conversion character at byte offset 6
```

Now,
```
Error: f-string: invalid conversion character at byte offset 7
```

This becomes more useful when there's whitespace between `!` and the flag value
although that is not valid but we can't detect that now.

## Test Plan

As mentioned above.
2023-10-05 17:46:14 +05:30
Dhruv Manilawala 69b8136463
Avoid curly brace escape in f-string format spec (#7780)
## 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
2023-10-03 19:38:03 +05:30
konsti 3ccd1d580d
Use crates.io unicode_names2 0.6.0 (#6478)
Update `unicode_names2` to the crates.io release 0.6.0, removing a git
dependency.
2023-10-02 18:17:38 -04:00
Charlie Marsh 2838f7af98
Skip all bracketed expressions when locating comparison ops (#7740)
Closes https://github.com/astral-sh/ruff/issues/7737.
2023-10-01 14:57:40 +00:00
Dhruv Manilawala e91ffe3e93
Consume the escaped Windows newline (`\r\n`) for `FStringMiddle` (#7722)
## 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
2023-10-01 07:58:20 +05:30
Dhruv Manilawala e72d617f4b
Remove escaped mac/windows eol from AST string value (#7724)
## Summary

This PR fixes the bug where the value of a string node type includes the
escaped mac/windows newline character.

Note that the token value still includes them, it's only removed when
parsing the string content.

## Test Plan

Add new test cases for the string node type to check that the escapes
aren't being included in the string value.

fixes: #7723
2023-10-01 07:37:59 +05:30
Dhruv Manilawala e62e245c61
Add support for PEP 701 (#7376)
## Summary

This PR adds support for PEP 701 in Ruff. This is a rollup PR of all the
other individual PRs. The separate PRs were created for logic separation
and code reviews. Refer to each pull request for a detail description on
the change.

Refer to the PR description for the list of pull requests within this PR.

## Test Plan

### Formatter ecosystem checks

Explanation for the change in ecosystem check:
https://github.com/astral-sh/ruff/pull/7597#issue-1908878183

#### `main`

```
| project      | similarity index  | total files       | changed files     |
|--------------|------------------:|------------------:|------------------:|
| cpython      |           0.76083 |              1789 |              1631 |
| django       |           0.99983 |              2760 |                36 |
| transformers |           0.99963 |              2587 |               319 |
| twine        |           1.00000 |                33 |                 0 |
| typeshed     |           0.99983 |              3496 |                18 |
| warehouse    |           0.99967 |               648 |                15 |
| zulip        |           0.99972 |              1437 |                21 |
```

#### `dhruv/pep-701`

```
| project      | similarity index  | total files       | changed files     |
|--------------|------------------:|------------------:|------------------:|
| cpython      |           0.76051 |              1789 |              1632 |
| django       |           0.99983 |              2760 |                36 |
| transformers |           0.99963 |              2587 |               319 |
| twine        |           1.00000 |                33 |                 0 |
| typeshed     |           0.99983 |              3496 |                18 |
| warehouse    |           0.99967 |               648 |                15 |
| zulip        |           0.99972 |              1437 |                21 |
```
2023-09-29 02:55:39 +00:00
Charlie Marsh f45281345d
Include radix base prefix in large number representation (#7700)
## 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`
2023-09-28 20:38:06 +00:00
konsti 4d16e2308d
Formatter and parser refactoring (#7569)
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)
2023-09-26 15:29:43 +02:00
Charlie Marsh 93b5d8a0fb
Implement our own small-integer optimization (#7584)
## 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`
2023-09-25 15:13:21 +00:00
Micha Reiser 8ce138760a
Emit `LexError` for dedent to incorrect level (#7638) 2023-09-25 11:45:44 +01:00
Chammika Mannakkara e41b08f1d0
Fix typo in infinite (#7614) 2023-09-23 11:19:36 +00:00
Charlie Marsh 4d6f5ff0a7
Remove `Int` wrapper type from parser (#7577)
## Summary

This is only used for the `level` field in relative imports (e.g., `from
..foo import bar`). It seems unnecessary to use a wrapper here, so this
PR changes to a `u32` directly.
2023-09-21 17:01:44 +00:00
Dhruv Manilawala a41bb2733f
Add range to lexer test snapshots (#7265)
## Summary

This PR updates the lexer test snapshots to include the range value as
well. This is mainly a mechanical refactor.

### Motivation

The main motivation is so that we can verify that the ranges are valid
and do not overlap.

## Test Plan

`cargo test`
2023-09-11 19:12:46 +00:00
Dhruv Manilawala f5701fcc63
Use snapshots for remaining lexer tests (#7264)
## Summary

This PR updates the remaining lexer test cases to use the snapshots.
This is mainly a mechanical refactor.

## Motivation

The main motivation is so that when we add the token range values to the
test case output, it's easier to update the test cases.

The reason they were not using the snapshots before was because of the usage of
`test_case` macro. The macros is mainly used for different EOL test cases. If we
just generate the snapshots directly, then the snapshot name would be suffixed
with `-1`, `-2`, etc. as the test function is still the same. So, we'll create
the snapshot ourselves with the platform name for the respective EOL
test cases.

## Test Plan

`cargo test`
2023-09-12 00:16:38 +05:30
Micha Reiser 7440e54ec6
Avoid allocating in lex_decimal (#7252) 2023-09-11 06:37:25 +00:00
Micha Reiser 842ff0212e
Add Lexer emoji test case (#7213) 2023-09-07 10:02:50 +00:00
Micha Reiser f1a4eb9c28
Use the unicode-ident crate (#7212) 2023-09-07 08:19:25 +00:00
Victor Hugo Gomes 041cdb95e0
Update identifier Unicode character validation to match Python spec (#7209)
Co-authored-by: Micha Reiser <micha@reiser.io>
2023-09-07 07:08:42 +00:00
Micha Reiser 171b66cb43
Lexer: Add skip whitespace fastpath (#7184) 2023-09-06 16:14:01 +02:00
Dhruv Manilawala 04f2842e4f
Move `ExprConstant::kind` to `StringConstant::unicode` (#7180) 2023-09-06 07:39:25 +00:00
Dhruv Manilawala 1adde24133
Rename parser mode from `Jupyter` to `Ipython` (#7153) 2023-09-05 14:12:26 +00:00
Charlie Marsh 68f605e80a
Fix `WithItem` ranges for parenthesized, non-`as` items (#6782)
## Summary

This PR attempts to address a problem in the parser related to the
range's of `WithItem` nodes in certain contexts -- specifically,
`WithItem` nodes in parentheses that do not have an `as` token after
them.

For example,
[here](https://play.ruff.rs/71be2d0b-2a04-4c7e-9082-e72bff152679):

```python
with (a, b):
    pass
```

The range of the `WithItem` `a` is set to the range of `(a, b)`, as is
the range of the `WithItem` `b`. In other words, when we have this kind
of sequence, we use the range of the entire parenthesized context,
rather than the ranges of the items themselves.

Note that this also applies to cases
[like](https://play.ruff.rs/c551e8e9-c3db-4b74-8cc6-7c4e3bf3713a):

```python
with (a, b, c as d):
    pass
```

You can see the issue in the parser here:

```rust
#[inline]
WithItemsNoAs: Vec<ast::WithItem> = {
    <location:@L> <all:OneOrMore<Test<"all">>> <end_location:@R> => {
        all.into_iter().map(|context_expr| ast::WithItem { context_expr, optional_vars: None, range: (location..end_location).into() }).collect()
    },
}
```

Fixing this issue is... very tricky. The naive approach is to use the
range of the `context_expr` as the range for the `WithItem`, but that
range will be incorrect when the `context_expr` is itself parenthesized.
For example, _that_ solution would fail here, since the range of the
first `WithItem` would be that of `a`, rather than `(a)`:

```python
with ((a), b):
    pass
```

The `with` parsing in general is highly precarious due to ambiguities in
the grammar. Changing it in _any_ way seems to lead to an ambiguous
grammar that LALRPOP fails to translate. Consensus seems to be that we
don't really understand _why_ the current grammar works (i.e., _how_ it
avoids these ambiguities as-is).

The solution implemented here is to avoid changing the grammar itself,
and instead change the shape of the nodes returned by various rules in
the grammar. Specifically, everywhere that we return `Expr`, we instead
return `ParenthesizedExpr`, which includes a parenthesized range and the
underlying `Expr` itself. (If an `Expr` isn't parenthesized, the ranges
will be equivalent.) In `WithItemsNoAs`, we can then use the
parenthesized range as the range for the `WithItem`.
2023-08-31 16:21:29 +01:00
Dhruv Manilawala 4d49d5e845
Add `eat_char2` for the lexer (#6968)
## Summary

This PR adds a new helper method on the `Cursor` called `eat_char2`
which is similar to `eat_char` but accepts 2 characters instead of 1. It'll
`bump` the cursor twice if both characters are found on lookahead.

## Test Plan

`cargo test`
2023-08-29 17:18:02 +05:30
Dhruv Manilawala 2893a9f6b5
Remove unused f-string error type (#6941) 2023-08-28 18:34:48 +05:30
Dhruv Manilawala 9c98416b96
Avoid lexer infinite loop on invalid input (#6937)
## Summary

This PR fixes a bug which sends the lexer into infinite loop for an invalid input.
The code in question is `[1` where the nesting is never finished. This means
that the lexer will keep emitting the `Err` token forever.

## Test Plan

Add a test case which collects all the tokens from the lexer. This just
makes sure that it doesn't go into infinite loop.
2023-08-28 17:21:38 +05:30
Charlie Marsh fc89976c24
Move `Ranged` into `ruff_text_size` (#6919)
## 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`
2023-08-27 14:12:51 -04:00
Charlie Marsh 15b73bdb8a
Introduce AST nodes for `PatternMatchClass` arguments (#6881)
## Summary

This PR introduces two new AST nodes to improve the representation of
`PatternMatchClass`. As a reminder, `PatternMatchClass` looks like this:

```python
case Point2D(0, 0, x=1, y=2):
  ...
```

Historically, this was represented as a vector of patterns (for the `0,
0` portion) and parallel vectors of keyword names (for `x` and `y`) and
values (for `1` and `2`). This introduces a bunch of challenges for the
formatter, but importantly, it's also really different from how we
represent similar nodes, like arguments (`func(0, 0, x=1, y=2)`) or
parameters (`def func(x, y)`).

So, firstly, we now use a single node (`PatternArguments`) for the
entire parenthesized region, making it much more consistent with our
other nodes. So, above, `PatternArguments` would be `(0, 0, x=1, y=2)`.

Secondly, we now have a `PatternKeyword` node for `x=1` and `y=2`. This
is much more similar to the how `Keyword` is represented within
`Arguments` for call expressions.

Closes https://github.com/astral-sh/ruff/issues/6866.

Closes https://github.com/astral-sh/ruff/issues/6880.
2023-08-26 14:45:44 +00:00
Micha Reiser 15b7525464
Rename parser goal 'All' to 'all' (#6867) 2023-08-25 12:00:57 +00:00
Dhruv Manilawala d1f07008f7
Rename Notebook related symbols (#6862)
This PR renames the following symbols:

* `PySourceType::Jupyter` -> `PySourceType::Ipynb`
* `SourceKind::Jupyter` -> `SourceKind::IpyNotebook`
* `JupyterIndex` -> `NotebookIndex`
2023-08-25 11:40:54 +05:30
Charlie Marsh d08f697a04
Remove lexing for colon-matching use cases (#6803)
It's much simpler to just search ahead for the first colon.
2023-08-23 04:44:51 +00:00
Dhruv Manilawala fb7caf43c8
Update lexer tests to use snapshots (#6658)
## Summary

This PR updates the lexer tests to use the snapshot testing framework.
It also
makes the following changes:
* Remove the use of macros in the lexer tests
* Use `test_case` for EOL tests

## Test Plan

```
cargo test --package ruff_python_parser --lib --all-features -- lexer::tests --no-capture
```
2023-08-22 18:23:19 +00:00
Charlie Marsh 6a5acde226
Make `Parameters` an optional field on `ExprLambda` (#6669)
## Summary

If a lambda doesn't contain any parameters, or any parameter _tokens_
(like `*`), we can use `None` for the parameters. This feels like a
better representation to me, since, e.g., what should the `TextRange` be
for a non-existent set of parameters? It also allows us to remove
several sites where we check if the `Parameters` is empty by seeing if
it contains any arguments, so semantically, we're already trying to
detect and model around this elsewhere.

Changing this also fixes a number of issues with dangling comments in
parameter-less lambdas, since those comments are now automatically
marked as dangling on the lambda. (As-is, we were also doing something
not-great whereby the lambda was responsible for formatting dangling
comments on the parameters, which has been removed.)

Closes https://github.com/astral-sh/ruff/issues/6646.

Closes https://github.com/astral-sh/ruff/issues/6647.

## Test Plan

`cargo test`
2023-08-18 15:34:54 +00:00
Charlie Marsh db1c556508
Implement `Ranged` on more structs (#6639)
## Summary

I noticed some inconsistencies around uses of `.range.start()`, structs
that have a `TextRange` field but don't implement `Ranged`, etc.

## Test Plan

`cargo test`
2023-08-17 11:22:39 -04:00
Charlie Marsh a70807e1e1
Expand `NamedExpr` range to include full range of parenthesized value (#6632)
## Summary

Given:

```python
if (
    x
    :=
    (  # 4
        y # 5
    )  # 6
):
    pass
```

It turns out the parser ended the range of the `NamedExpr` at the end of
`y`, rather than the end of the parenthesis that encloses `y`. This just
seems like a bug -- the range should be from the start of the name on
the left, to the end of the parenthesized node on the right.

## Test Plan

`cargo test`
2023-08-17 14:34:05 +00:00
Charlie Marsh 96d310fbab
Remove `Stmt::TryStar` (#6566)
## Summary

Instead, we set an `is_star` flag on `Stmt::Try`. This is similar to the
pattern we've migrated towards for `Stmt::For` (removing
`Stmt::AsyncFor`) and friends. While these are significant differences
for an interpreter, we tend to handle these cases identically or nearly
identically.

## Test Plan

`cargo test`
2023-08-14 13:39:44 -04:00
Charlie Marsh f16e780e0a
Add an implicit concatenation flag to string and bytes constants (#6512)
## Summary

Per the discussion in
https://github.com/astral-sh/ruff/discussions/6183, this PR adds an
`implicit_concatenated` flag to the string and bytes constant variants.
It's not actually _used_ anywhere as of this PR, but it is covered by
the tests.

Specifically, we now use a struct for the string and bytes cases, along
with the `Expr::FString` node. That struct holds the value, plus the
flag:

```rust
#[derive(Clone, Debug, PartialEq, is_macro::Is)]
pub enum Constant {
    Str(StringConstant),
    Bytes(BytesConstant),
    ...
}

#[derive(Clone, Debug, PartialEq, Eq)]
pub struct StringConstant {
    /// The string value as resolved by the parser (i.e., without quotes, or escape sequences, or
    /// implicit concatenations).
    pub value: String,
    /// Whether the string contains multiple string tokens that were implicitly concatenated.
    pub implicit_concatenated: bool,
}

impl Deref for StringConstant {
    type Target = str;
    fn deref(&self) -> &Self::Target {
        self.value.as_str()
    }
}

#[derive(Clone, Debug, PartialEq, Eq)]
pub struct BytesConstant {
    /// The bytes value as resolved by the parser (i.e., without quotes, or escape sequences, or
    /// implicit concatenations).
    pub value: Vec<u8>,
    /// Whether the string contains multiple string tokens that were implicitly concatenated.
    pub implicit_concatenated: bool,
}

impl Deref for BytesConstant {
    type Target = [u8];
    fn deref(&self) -> &Self::Target {
        self.value.as_slice()
    }
}
```

## Test Plan

`cargo test`
2023-08-14 13:46:54 +00:00
Micha Reiser 9584f613b9
Remove `allow(pedantic)` from formatter (#6549) 2023-08-14 14:02:06 +02:00
Dhruv Manilawala 6a64f2289b
Rename `Magic*` to `IpyEscape*` (#6395)
## Summary

This PR renames the `MagicCommand` token to `IpyEscapeCommand` token and
`MagicKind` to `IpyEscapeKind` type to better reflect the purpose of the
token and type. Similarly, it renames the AST nodes from `LineMagic` to
`IpyEscapeCommand` prefixed with `Stmt`/`Expr` wherever necessary.

It also makes renames from using `jupyter_magic` to
`ipython_escape_commands` in various function names.

The mode value is still `Mode::Jupyter` because the escape commands are
part of the IPython syntax but the lexing/parsing is done for a Jupyter
notebook.

### Motivation behind the rename:
* IPython codebase defines it as "EscapeCommand" / "Escape Sequences":
* Escape Sequences:
292e3a2345/IPython/core/inputtransformer2.py (L329-L333)
* Escape command:
292e3a2345/IPython/core/inputtransformer2.py (L410-L411)
* The word "magic" is used mainly for the actual magic commands i.e.,
the ones starting with `%`/`%%`
(https://ipython.readthedocs.io/en/stable/interactive/reference.html#magic-command-system).
So, this avoids any confusion between the Magic token (`%`, `%%`) and
the escape command itself.
## Test Plan

* `cargo test` to make sure all renames are done correctly.
* `grep` for `jupyter_escape`/`magic` to make sure all renames are done
correctly.
2023-08-09 13:28:18 +00:00
Dhruv Manilawala e257c5af32
Add support for help end IPython escape commands (#6358)
## Summary

This PR adds support for a stricter version of help end escape
commands[^1] in the parser. By stricter, I mean that the escape tokens
are only at the end of the command and there are no tokens at the start.
This makes it difficult to implement it in the lexer without having to
do a lot of look aheads or keeping track of previous tokens.

Now, as we're adding this in the parser, the lexer needs to recognize
and emit a new token for `?`. So, `Question` token is added which will
be recognized only in `Jupyter` mode.

The conditions applied are the same as the ones in the original
implementation in IPython codebase (which is a regex):
* There can only be either 1 or 2 question mark(s) at the end
* The node before the question mark can be a `Name`, `Attribute`,
`Subscript` (only with integer constants in slice position), or any
combination of the 3 nodes.

## Test Plan

Added test cases for various combination of the possible nodes in the
command value position and update the snapshots.

fixes: #6359
fixes: #5030 (This is the final piece)

[^1]: https://github.com/astral-sh/ruff/pull/6272#issue-1833094281
2023-08-09 10:28:52 +05:30
Charlie Marsh 3f0eea6d87
Rename `JoinedStr` to `FString` in the AST (#6379)
## Summary

Per the proposal in https://github.com/astral-sh/ruff/discussions/6183,
this PR renames the `JoinedStr` node to `FString`.
2023-08-07 17:33:17 +00:00
Charlie Marsh daefa74e9a
Remove async AST node variants for `with`, `for`, and `def` (#6369)
## Summary

Per the suggestion in
https://github.com/astral-sh/ruff/discussions/6183, this PR removes
`AsyncWith`, `AsyncFor`, and `AsyncFunctionDef`, replacing them with an
`is_async` field on the non-async variants of those structs. Unlike an
interpreter, we _generally_ have identical handling for these nodes, so
separating them into distinct variants adds complexity from which we
don't really benefit. This can be seen below, where we get to remove a
_ton_ of code related to adding generic `Any*` wrappers, and a ton of
duplicate branches for these cases.

## Test Plan

`cargo test` is unchanged, apart from parser snapshots.
2023-08-07 16:36:02 +00:00
Dhruv Manilawala e4a4660925
Support help end escape command with priority (#6272)
## Summary

This PR adds support for help end escape command in the lexer.

### What are "help end escape commands"?

First, the escape commands are special IPython syntax which enhances the
functionality for the IPython REPL. There are 9 types of escape kinds
which are recognized by the tokens which are present at the start of the
command (`?`, `??`, `!`, `!!`, etc.).

Here, the help command is using either the `?` or `??` token at the
start (`?str.replace` for example). Those 2 tokens are also supported
when they're at the end of the command (`str.replace?`), but the other
tokens aren't supported in that position.

There are mainly two types of help end escape commands:
1. Ending with either `?` or `??`, but it also starts with one of the
escape tokens (`%matplotlib?`)
2. On the other hand, there's a stricter version for (1) which doesn't
start with any escape tokens (`str.replace?`)

This PR adds support for (1) while (2) will be supported in the parser.

### Priority

Now, if the command starts and ends with an escape token, how do we
decide the kind of this command? This is where priority comes into
picture. This is simple as there's only one priority where `?`/`??` at
the end takes priority over any other escape token and all of the other
tokens are at the same priority. Remember that only `?`/`??` at the end
is considered valid.

This is mainly useful in the case where someone would want to invoke the
help command on the magic command itself. For example, in `%matplotlib?`
the help command takes priority which means that we want help for the
`matplotlib` magic function instead of calling the magic function
itself.

### Specification

Here's where things get a bit tricky. What if there are question mark
tokens at both ends. How do we decide if it's `Help` (`?`) kind or
`Help2` (`??`) kind?

|     | Magic       | Value     | Kind    |
| --- | ---         | ---       | ---     |
| 1   | `?foo?`     | `foo`     | `Help`  |
| 2   | `??foo?`    | `foo`     | `Help`  |
| 3   | `?foo??`    | `foo`     | `Help2` |
| 4   | `??foo??`   | `foo`     | `Help2` |
| 5   | `???foo??`  | `foo`     | `Help2` |
| 6   | `??foo???`  | `foo???`  | `Help2` |
| 7   | `???foo???` | `?foo???` | `Help2` |

Looking at the above table:

- The question mark tokens on the right takes priority over the ones on
the left but only if the number of question mark on the right is 1 or 2.
- If there are more than 2 question mark tokens on the right side, then
the left side is used to determine the same.
- If the right side is used to determine the kind, then all of the
question marks and whitespaces on the left side are ignored in the
`value`, but if it’s the other way around, then all of the extra
question marks are part of the `value`.

### References

- IPython implementation using the regex:
292e3a2345/IPython/core/inputtransformer2.py (L454-L462)
- Priorities:
292e3a2345/IPython/core/inputtransformer2.py (L466-L469)

## Test Plan

Add a bunch of test cases for the lexer and verify that it matches the
behavior of
IPython transformer.

resolves: #6357
2023-08-07 21:01:02 +05:30
Dhruv Manilawala 32fa05765a
Use `Jupyter` mode while parsing Notebook files (#5552)
## Summary

Enable using the new `Mode::Jupyter` for the tokenizer/parser to parse
Jupyter line magic tokens.

The individual call to the lexer i.e., `lex_starts_at` done by various
rules should consider the context of the source code (is this content
from a Jupyter Notebook?). Thus, a new field `source_type` (of type
`PySourceType`) is added to `Checker` which is being passed around as an
argument to the relevant functions. This is then used to determine the
`Mode` for the lexer.

## Test Plan

Add new test cases to make sure that the magic statement is considered
while generating the diagnostic and autofix:
* For `I001`, if there's a magic statement in between two import blocks,
they should be sorted independently

fixes: #6090
2023-08-05 00:32:07 +00:00
Charlie Marsh 8a0f844642
Box type params and arguments fields on the class definition node (#6275)
## Summary

This PR boxes the `TypeParams` and `Arguments` fields on the class
definition node. These fields are optional and often emitted, and given
that class definition is our largest enum variant, we pay the cost of
including them for every statement in the AST. Boxing these types
reduces the statement size by 40 bytes, which seems like a good tradeoff
given how infrequently these are accessed.

## Test Plan

Need to benchmark, but no behavior changes.
2023-08-02 16:47:06 +00:00
Charlie Marsh b095b7204b
Add a `TypeParams` node to the AST (#6261)
## Summary

Similar to #6259, this PR adds a `TypeParams` node to the AST, to
capture the list of type parameters with their surrounding brackets.

If a statement lacks type parameters, the `type_params` field will be
`None`.
2023-08-02 14:12:45 +00:00
Charlie Marsh 981e64f82b
Introduce an `Arguments` AST node for function calls and class definitions (#6259)
## Summary

This PR adds a new `Arguments` AST node, which we can use for function
calls and class definitions.

The `Arguments` node spans from the left (open) to right (close)
parentheses inclusive.

In the case of classes, the `Arguments` is an option, to differentiate
between:

```python
# None
class C: ...

# Some, with empty vectors
class C(): ...
```

In this PR, we don't really leverage this change (except that a few
rules get much simpler, since we don't need to lex to find the start and
end ranges of the parentheses, e.g.,
`crates/ruff/src/rules/pyupgrade/rules/lru_cache_without_parameters.rs`,
`crates/ruff/src/rules/pyupgrade/rules/unnecessary_class_parentheses.rs`).

In future PRs, this will be especially helpful for the formatter, since
we can track comments enclosed on the node itself.

## Test Plan

`cargo test`
2023-08-02 10:01:13 -04:00
Charlie Marsh 9c708d8fc1
Rename `Parameter#arg` and `ParameterWithDefault#def` fields (#6255)
## Summary

This PR renames...

- `Parameter#arg` to `Parameter#name`
- `ParameterWithDefault#def` to `ParameterWithDefault#parameter` (such
that `ParameterWithDefault` has a `default` and a `parameter`)

## Test Plan

`cargo test`
2023-08-01 14:28:34 -04:00
Charlie Marsh adc8bb7821
Rename `Arguments` to `Parameters` in the AST (#6253)
## Summary

This PR renames a few AST nodes for clarity:

- `Arguments` is now `Parameters`
- `Arg` is now `Parameter`
- `ArgWithDefault` is now `ParameterWithDefault`

For now, the attribute names that reference `Parameters` directly are
changed (e.g., on `StmtFunctionDef`), but the attributes on `Parameters`
itself are not (e.g., `vararg`). We may revisit that decision in the
future.

For context, the AST node formerly known as `Arguments` is used in
function definitions. Formally (outside of the Python context),
"arguments" typically refers to "the values passed to a function", while
"parameters" typically refers to "the variables used in a function
definition". E.g., if you Google "arguments vs parameters", you'll get
some explanation like:

> A parameter is a variable in a function definition. It is a
placeholder and hence does not have a concrete value. An argument is a
value passed during function invocation.

We're thus deviating from Python's nomenclature in favor of a scheme
that we find to be more precise.
2023-08-01 13:53:28 -04:00
konsti 1df7e9831b
Replace `.map_or(false, $closure)` with `.is_some_and(closure)` (#6244)
**Summary**
[Option::is_some_and](https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.is_some_and)
and
[Result::is_ok_and](https://doc.rust-lang.org/std/result/enum.Result.html#method.is_ok_and)
are new methods is rust 1.70. I find them way more readable than
`.map_or(false, ...)`.

The changes are `s/.map_or(false,/.is_some_and(/g`, then manually
switching to `is_ok_and` where the value is a Result rather than an
Option.

**Test Plan** n/a^
2023-08-01 19:29:42 +02:00
Micha Reiser debfca3a11
Remove `Parse` trait (#6235) 2023-08-01 18:35:03 +02:00
Micha Reiser f45e8645d7
Remove unused parser modes
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## Summary

This PR removes the `Interactive` and `FunctionType` parser modes that are unused by ruff

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## Test Plan

`cargo test`

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2023-08-01 13:10:07 +02:00
Micha Reiser 7c7231db2e
Remove unsupported `type_comment` field
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## Summary

This PR removes the `type_comment` field which our parser doesn't support.

<!-- What's the purpose of the change? What does it do, and why? -->

## Test Plan

`cargo test`

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2023-08-01 12:53:13 +02:00
Micha Reiser 4ad5903ef6
Delete type-ignore node
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## Summary

This PR removes the type ignore node from the AST because our parser doesn't support it, and just having it around is confusing.

<!-- What's the purpose of the change? What does it do, and why? -->

## Test Plan

`cargo build`

<!-- How was it tested? -->
2023-08-01 12:34:50 +02:00
David Szotten ba990b676f
add `DebugText` for self-documenting f-strings (#6167) 2023-08-01 07:55:03 +02:00
Micha Reiser 40f54375cb
Pull in RustPython parser (#6099) 2023-07-27 09:29:11 +00:00
Micha Reiser 2cf00fee96
Remove parser dependency from ruff-python-ast (#6096) 2023-07-26 17:47:22 +02:00