## Summary
Check that the sequence type is a list, set, dict, or tuple before
recommending replacing the `enumerate(...)` call with `range(len(...))`.
Document behaviour so users are aware of the type inference limitation
leading to false negatives.
Closes#7656.
## 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supported range (e.g., `outdated-version-block`).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`
## Summary
We have a few rules that rely on detecting whether two statements are in
different branches -- for example, different arms of an `if`-`else`.
Historically, the way this was implemented is that, given two statement
IDs, we'd find the common parent (by traversing upwards via our
`Statements` abstraction); then identify branches "manually" by matching
the parents against `try`, `if`, and `match`, and returning iterators
over the arms; then check if there's an arm for which one of the
statements is a child, and the other is not.
This has a few drawbacks:
1. First, the code is generally a bit hard to follow (Konsti mentioned
this too when working on the `ElifElseClause` refactor).
2. Second, this is the only place in the codebase where we need to go
from `&Stmt` to `StatementID` -- _everywhere_ else, we only need to go
in the _other_ direction. Supporting these lookups means we need to
maintain a mapping from `&Stmt` to `StatementID` that includes every
`&Stmt` in the program. (We _also_ end up maintaining a `depth` level
for every statement.) I'd like to get rid of these requirements to
improve efficiency, reduce complexity, and enable us to treat AST modes
more generically in the future. (When I looked at adding the `&Expr` to
our existing statement-tracking infrastructure, maintaining a hash map
with all the statements noticeably hurt performance.)
The solution implemented here instead makes branches a first-class
concept in the semantic model. Like with `Statements`, we now have a
`Branches` abstraction, where each branch points to its optional parent.
When we store statements, we store the `BranchID` alongside each
statement. When we need to detect whether two statements are in the same
branch, we just realize each statement's branch path and compare the
two. (Assuming that the two statements are in the same scope, then
they're on the same branch IFF one branch path is a subset of the other,
starting from the top.) We then add some calls to the visitor to push
and pop branches in the appropriate places, for `if`, `try`, and `match`
statements.
Note that a branch is not 1:1 with a statement; instead, each branch is
closer to a suite, but not _every_ suite is a branch. For example, each
arm in an `if`-`elif`-`else` is a branch, but the `else` in a `for` loop
is not considered a branch.
In addition to being much simpler, this should also be more efficient,
since we've shed the entire `&Stmt` hash map, plus the `depth` that we
track on `StatementWithParent` in favor of a single `Option<BranchID>`
on `StatementWithParent` plus a single vector for all branches. The
lookups should be faster too, since instead of doing a bunch of jumps
around with the hash map + repeated recursive calls to find the common
parents, we instead just do a few simple lookups in the `Branches`
vector to realize and compare the branch paths.
## Test Plan
`cargo test` -- we have a lot of coverage for this, which we inherited
from PyFlakes
## 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`
## Summary
Fixes some TODOs introduced in
https://github.com/astral-sh/ruff/pull/6538. In short, given an
expression like `1 if x > 0 else "Hello, world!"`, we now return a union
type that says the expression can resolve to either an `int` or a `str`.
The system remains very limited, it only works for obvious primitive
types, and there's no attempt to do inference on any more complex
variables. (If any expression yields `Unknown` or `TypeError`, we
propagate that result throughout and abort on the client's end.)
## Summary
This PR leverages the unified function definition node to add precise
AST node types to `MemberKind`, which is used to power our docstring
definition tracking (e.g., classes and functions, whether they're
methods or functions or nested functions and so on, whether they have a
docstring, etc.). It was painful to do this in the past because the
function variants needed to support a union anyway, but storing precise
nodes removes like a dozen panics.
No behavior changes -- purely a refactor.
## Test Plan
`cargo test`
## 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.
## Summary
This PR fixes the performance degradation introduced in
https://github.com/astral-sh/ruff/pull/6345. Instead of using the
generic `Nodes` structs, we now use separate `Statement` and
`Expression` structs. Importantly, we can avoid tracking a bunch of
state for expressions that we need for parents: we don't need to track
reference-to-ID pointers (we just have no use-case for this -- I'd
actually like to remove this from statements too, but we need it for
branch detection right now), we don't need to track depth, etc.
In my testing, this entirely removes the regression on all-rules, and
gets us down to 2ms slower on the default rules (as a crude hyperfine
benchmark, so this is within margin of error IMO).
No behavioral changes.
## Summary
This PR removes a now-unnecessary abstraction from `helper.rs`
(`CallArguments`), in favor of adding methods to `Arguments` directly,
which helps with discoverability.
## 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`
## Summary
This PR adds a `logger-objects` setting that allows users to mark
specific symbols a `logging.Logger` objects. Currently, if a `logger` is
imported, we only flagged it as a `logging.Logger` if it comes exactly
from the `logging` module or is `flask.current_app.logger`.
This PR allows users to mark specific loggers, like
`logging_setup.logger`, to ensure that they're covered by the
`flake8-logging-format` rules and others.
For example, if you have a module `logging_setup.py` with the following
contents:
```python
import logging
logger = logging.getLogger(__name__)
```
Adding `"logging_setup.logger"` to `logger-objects` will ensure that
`logging_setup.logger` is treated as a `logging.Logger` object when
imported from other modules (e.g., `from logging_setup import logger`).
Closes https://github.com/astral-sh/ruff/issues/5694.
## Summary
Previously, `StmtIf` was defined recursively as
```rust
pub struct StmtIf {
pub range: TextRange,
pub test: Box<Expr>,
pub body: Vec<Stmt>,
pub orelse: Vec<Stmt>,
}
```
Every `elif` was represented as an `orelse` with a single `StmtIf`. This
means that this representation couldn't differentiate between
```python
if cond1:
x = 1
else:
if cond2:
x = 2
```
and
```python
if cond1:
x = 1
elif cond2:
x = 2
```
It also makes many checks harder than they need to be because we have to
recurse just to iterate over an entire if-elif-else and because we're
lacking nodes and ranges on the `elif` and `else` branches.
We change the representation to a flat
```rust
pub struct StmtIf {
pub range: TextRange,
pub test: Box<Expr>,
pub body: Vec<Stmt>,
pub elif_else_clauses: Vec<ElifElseClause>,
}
pub struct ElifElseClause {
pub range: TextRange,
pub test: Option<Expr>,
pub body: Vec<Stmt>,
}
```
where `test: Some(_)` represents an `elif` and `test: None` an else.
This representation is different tradeoff, e.g. we need to allocate the
`Vec<ElifElseClause>`, the `elif`s are now different than the `if`s
(which matters in rules where want to check both `if`s and `elif`s) and
the type system doesn't guarantee that the `test: None` else is actually
last. We're also now a bit more inconsistent since all other `else`,
those from `for`, `while` and `try`, still don't have nodes. With the
new representation some things became easier, e.g. finding the `elif`
token (we can use the start of the `ElifElseClause`) and formatting
comments for if-elif-else (no more dangling comments splitting, we only
have to insert the dangling comment after the colon manually and set
`leading_alternate_branch_comments`, everything else is taken of by
having nodes for each branch and the usual placement.rs fixups).
## Merge Plan
This PR requires coordination between the parser repo and the main ruff
repo. I've split the ruff part, into two stacked PRs which have to be
merged together (only the second one fixes all tests), the first for the
formatter to be reviewed by @michareiser and the second for the linter
to be reviewed by @charliermarsh.
* MH: Review and merge
https://github.com/astral-sh/RustPython-Parser/pull/20
* MH: Review and merge or move later in stack
https://github.com/astral-sh/RustPython-Parser/pull/21
* MH: Review and approve
https://github.com/astral-sh/RustPython-Parser/pull/22
* MH: Review and approve formatter PR
https://github.com/astral-sh/ruff/pull/5459
* CM: Review and approve linter PR
https://github.com/astral-sh/ruff/pull/5460
* Merge linter PR in formatter PR, fix ecosystem checks (ecosystem
checks can't run on the formatter PR and won't run on the linter PR, so
we need to merge them first)
* Merge https://github.com/astral-sh/RustPython-Parser/pull/22
* Create tag in the parser, update linter+formatter PR
* Merge linter+formatter PR https://github.com/astral-sh/ruff/pull/5459
---------
Co-authored-by: Micha Reiser <micha@reiser.io>
## Summary
The AST pass is broken up into three phases: pre-visit (which includes
analysis), recurse (visit all members), and post-visit (clean-up). We're
not supposed to edit semantic model flags in the pre-visit phase, but it
looks like we were for literal detection. This didn't matter in
practice, but I'm looking into some AST refactors for which this _does_
cause issues.
No behavior changes expected.
## Test Plan
Good test coverage on these.
## Summary
Python doesn't allow `"Foo" | None` if the annotation will be evaluated
at runtime (see the comments in the PR, or the semantic model
documentation for more on what this means and when it is true), but it
_does_ allow it if the annotation is typing-only.
This, for example, is invalid, as Python will evaluate `"Foo" | None` at
runtime in order to
populate the function's `__annotations__`:
```python
def f(x: "Foo" | None): ...
```
This, however, is valid:
```python
def f():
x: "Foo" | None
```
As is this:
```python
from __future__ import annotations
def f(x: "Foo" | None): ...
```
Closes#5706.
Support for `let…else` formatting was just merged to nightly
(rust-lang/rust#113225). Rerun `cargo fmt` with Rust nightly 2023-07-02
to pick this up. Followup to #939.
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
## Summary
This PR upgrade RustPython to pull in the changes to `Arguments` (zip
defaults with their identifiers) and all the renames to `CmpOp` and
friends.
## Summary
After #5140, I audited the codebase for similar patterns (defining a
list of `CallPath` entities in a static vector, then looping over them
to pattern-match). This PR migrates all other such cases to use `match`
and `matches!` where possible.
There are a few benefits to this:
1. It more clearly denotes the intended semantics (branches are
exclusive).
2. The compiler can help deduplicate the patterns and detect unreachable
branches.
3. Performance: in the benchmark below, the all-rules performance is
increased by nearly 10%...
## Benchmarks
I decided to benchmark against a large file in the Airflow repository
with a lot of type annotations
([`views.py`](https://raw.githubusercontent.com/apache/airflow/f03f73100e8a7d6019249889de567cb00e71e457/airflow/www/views.py)):
```
linter/default-rules/airflow/views.py
time: [10.871 ms 10.882 ms 10.894 ms]
thrpt: [19.739 MiB/s 19.761 MiB/s 19.781 MiB/s]
change:
time: [-2.7182% -2.5687% -2.4204%] (p = 0.00 < 0.05)
thrpt: [+2.4805% +2.6364% +2.7942%]
Performance has improved.
linter/all-rules/airflow/views.py
time: [24.021 ms 24.038 ms 24.062 ms]
thrpt: [8.9373 MiB/s 8.9461 MiB/s 8.9527 MiB/s]
change:
time: [-8.9537% -8.8516% -8.7527%] (p = 0.00 < 0.05)
thrpt: [+9.5923% +9.7112% +9.8342%]
Performance has improved.
Found 12 outliers among 100 measurements (12.00%)
5 (5.00%) high mild
7 (7.00%) high severe
```
The impact is dramatic -- nearly a 10% improvement for `all-rules`.
## Summary
This PR consistently uses `matches! for static `CallPath` comparisons.
In some cases, we can significantly reduce the number of cases or
checks.
## Test Plan
`cargo test `
## Summary
As discussed in Discord, and similar to oxc, we're going to refer to
this as `.semantic()` everywhere.
While I was auditing usages of `model: &SemanticModel`, I also changed
as many function signatures as I could find to consistently take the
model as the _last_ argument, rather than the first.
