-
Notifications
You must be signed in to change notification settings - Fork 1.1k
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
[ruff
] Detect unnecessary dict
comprehensions for iterables (RUF025
)
#9613
Merged
Merged
Changes from 7 commits
Commits
Show all changes
13 commits
Select commit
Hold shift + click to select a range
0c91ac8
[RUF] - Add unnecessary dict comprehension rule (RUF023)
vai-mikkoleppanen 9e7b476
merge with main and rename rule to RUF025
vai-mikkoleppanen 4105716
fix linux tests and use new rule name RUF025
vai-mikkoleppanen c4b16aa
merge with main
vai-mikkoleppanen cdb3e96
reverted flake8 snapshots
vai-mikkoleppanen 1e3e24b
fix: don't provide suggestion if comprehension contains nested loops …
vai-mikkoleppanen 99a57f4
code review fixes
vai-mikkoleppanen 10da052
Merge branch 'main' into add-RUF025
charliermarsh 0b4584d
Tweaks
charliermarsh 5de6750
format fixture
charliermarsh d6e1395
Re-enable name detection
charliermarsh ebf534a
Fix Clippy
charliermarsh 3cca228
Fix if
charliermarsh File filter
Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,66 @@ | ||
# Violation cases: RUF025 | ||
|
||
def foo(): | ||
numbers = [1,2,3] | ||
{n: None for n in numbers} # RUF025 | ||
|
||
def foo(): | ||
for key, value in {n: 1 for n in [1,2,3]}.items(): # RUF025 | ||
pass | ||
|
||
def foo(): | ||
{n: 1.1 for n in [1,2,3]} # RUF025 | ||
|
||
def foo(): | ||
{n: complex(3, 5) for n in [1,2,3]} # RUF025 | ||
|
||
def foo(): | ||
def f(data): | ||
return data | ||
f({c: "a" for c in "12345"}) # RUF025 | ||
|
||
def foo(): | ||
{n: True for n in [1,2,2]} # RUF025 | ||
|
||
def foo(): | ||
{n: b'hello' for n in (1,2,2)} # RUF025 | ||
|
||
def foo(): | ||
{n: ... for n in [1,2,3]} # RUF025 | ||
|
||
def foo(): | ||
values = ["a", "b", "c"] | ||
[{n: values for n in [1,2,3]}] # RUF025 | ||
|
||
def foo(): | ||
def f(): | ||
return 1 | ||
|
||
a = f() | ||
{n: a for n in [1,2,3]} # RUF025 | ||
|
||
def foo(): | ||
{n: False for n in {1: "a", 2: "b"}} # RUF025 | ||
|
||
|
||
# Non-violation cases: RUF025 | ||
|
||
def foo(): | ||
{n: 1 for n in [1,2,3,4,5] if n < 3} # OK | ||
|
||
def foo(): | ||
{n: 1 for c in [1,2,3,4,5] for n in [1,2,3] if c < 3} # OK | ||
|
||
def foo(): | ||
def f(): | ||
pass | ||
{n: f() for n in [1,2,3]} # OK | ||
|
||
def foo(): | ||
{n: n for n in [1,2,3,4,5]} # OK | ||
|
||
def foo(): | ||
def f(): | ||
return {n: 1 for c in [1,2,3,4,5] for n in [1,2,3]} # OK | ||
|
||
f() |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
|
@@ -9,4 +9,3 @@ EXE001_1.py:1:1: EXE001 Shebang is present but file is not executable | |
3 | if __name__ == '__main__': | ||
| | ||
|
||
|
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
146 changes: 146 additions & 0 deletions
146
crates/ruff_linter/src/rules/ruff/rules/unnecessary_dict_comprehension_for_iterable.rs
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,146 @@ | ||
use ast::ExprName; | ||
use ruff_diagnostics::{AlwaysFixableViolation, Diagnostic, Edit, Fix}; | ||
use ruff_macros::{derive_message_formats, violation}; | ||
use ruff_python_ast::{self as ast, Arguments, Comprehension, Expr, ExprCall, ExprContext}; | ||
use ruff_text_size::{Ranged, TextRange}; | ||
|
||
use crate::checkers::ast::Checker; | ||
|
||
/// ## What it does | ||
/// Checks for unnecessary `dict` comprehension when creating a new dictionary from iterable. | ||
/// | ||
/// ## Why is this bad? | ||
/// It's unnecessary to use a `dict` comprehension to build a dictionary from an iterable when the value is `static`. | ||
/// Use `dict.fromkeys(iterable)` instead of `{value: None for value in iterable}`. | ||
/// | ||
/// `dict.fromkeys(iterable)` is more readable and faster than `{value: None for value in iterable}`. | ||
/// | ||
/// | ||
/// ## Examples | ||
/// ```python | ||
/// {a: None for a in iterable} | ||
/// {a: 1 for a in iterable} | ||
/// ``` | ||
/// | ||
/// Use instead: | ||
/// ```python | ||
/// dict.fromkeys(iterable) | ||
/// dict.fromkeys(iterable, 1) | ||
/// ``` | ||
#[violation] | ||
pub struct UnnecessaryDictComprehensionForIterable { | ||
is_value_none_literal: bool, | ||
} | ||
|
||
impl AlwaysFixableViolation for UnnecessaryDictComprehensionForIterable { | ||
#[derive_message_formats] | ||
fn message(&self) -> String { | ||
if self.is_value_none_literal { | ||
format!( | ||
"Unnecessary dict comprehension for iterable (rewrite using `dict.fromkeys(iterable)`)" | ||
) | ||
} else { | ||
format!( | ||
"Unnecessary dict comprehension for iterable (rewrite using `dict.fromkeys(iterable, value)`)" | ||
) | ||
} | ||
} | ||
|
||
fn fix_title(&self) -> String { | ||
if self.is_value_none_literal { | ||
format!("Rewrite using `dict.fromkeys(iterable, value)`)",) | ||
} else { | ||
format!("Rewrite using `dict.fromkeys(iterable)`)") | ||
} | ||
} | ||
} | ||
|
||
/// RUF025 | ||
pub(crate) fn unnecessary_dict_comprehension_for_iterable( | ||
checker: &mut Checker, | ||
expr: &Expr, | ||
key: &Expr, | ||
value: &Expr, | ||
generators: &[Comprehension], | ||
) { | ||
let [generator] = generators else { | ||
return; | ||
}; | ||
|
||
// Don't suggest `dict.fromkeys` for: | ||
// - async generator expressions, because `dict.fromkeys` is not async. | ||
// - nested generator expressions, because `dict.fromkeys` might be error-prone option at least for fixing. | ||
// - generator expressions with `if` clauses, because `dict.fromkeys` might not be valid option. | ||
if !generator.ifs.is_empty() && generator.is_async { | ||
return; | ||
} | ||
|
||
if !generator.target.is_name_expr() { | ||
return; | ||
}; | ||
|
||
// Don't suggest `dict.fromkeys` if key and value are binded to the same name. | ||
if let (Expr::Name(key_name), Expr::Name(value_name)) = (key, value) { | ||
if key_name.id == value_name.id { | ||
return; | ||
} | ||
} | ||
|
||
if !has_valid_expression_type(value) { | ||
return; | ||
} | ||
|
||
let mut diagnostic = Diagnostic::new( | ||
UnnecessaryDictComprehensionForIterable { | ||
is_value_none_literal: value.is_none_literal_expr(), | ||
}, | ||
expr.range(), | ||
); | ||
|
||
diagnostic.set_fix(Fix::safe_edit(Edit::range_replacement( | ||
checker | ||
.generator() | ||
.expr(&fix_unnecessary_dict_comprehension(value, generator)), | ||
expr.range(), | ||
))); | ||
checker.diagnostics.push(diagnostic); | ||
} | ||
|
||
// only accept `None`, `Ellipsis`, `True`, `False`, `Number`, `String`, `Bytes`, `Name` as value | ||
fn has_valid_expression_type(node: &ast::Expr) -> bool { | ||
matches!( | ||
node, | ||
ast::Expr::StringLiteral(_) | ||
| ast::Expr::BytesLiteral(_) | ||
| ast::Expr::NumberLiteral(_) | ||
| ast::Expr::BooleanLiteral(_) | ||
| ast::Expr::NoneLiteral(_) | ||
| ast::Expr::EllipsisLiteral(_) | ||
| ast::Expr::Name(_) | ||
) | ||
} | ||
|
||
/// Generate a [`Fix`] to replace `dict` comprehension with `dict.fromkeys`. | ||
/// (RUF025) Convert `{n: None for n in [1,2,3]}` to `dict.fromkeys([1,2,3])` or | ||
/// `{n: 1 for n in [1,2,3]}` to `dict.fromkeys([1,2,3], 1)`. | ||
fn fix_unnecessary_dict_comprehension(value: &Expr, generator: &Comprehension) -> Expr { | ||
let iterable = generator.iter.clone(); | ||
let args = Arguments { | ||
args: if value.is_none_literal_expr() { | ||
vec![iterable] | ||
} else { | ||
vec![iterable, value.clone()] | ||
}, | ||
keywords: vec![], | ||
range: TextRange::default(), | ||
}; | ||
Expr::Call(ExprCall { | ||
func: Box::new(Expr::Name(ExprName { | ||
id: "dict.fromkeys".into(), | ||
ctx: ExprContext::Load, | ||
range: TextRange::default(), | ||
})), | ||
arguments: args, | ||
range: TextRange::default(), | ||
}) | ||
} |
Oops, something went wrong.
Oops, something went wrong.
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
nit: we could use an enum instead of a boolean. A boolean value is hard to read until it is linked with some context like a variable name. An enum can prove to be readable in such cases.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Yea, I thought about using an Enum but it kind of felt slightly over board for such a simple thing.