[wps-light] Implemented assignment-to-subscript-slice (WPS362)

crates/ruff_linter/resources/test/fixtures/wps_light/WPS362.py

@@ -0,0 +1,18 @@
+a[1:3] = [1, 2]
+a[slice(1)] = [1, 3]
+
+a[:0], a[-1:] = prefix, suffix
+
+a[:] = complete_replacement
+
+a[0:0] = prepend
+
+a[0] = 1
+
+
+size = 3
+board = [["_"] * size for _ in range(size)]
+
+board[0:1][1:2] = "X"
+
+board[0] = board[0:1] = board[1:2] = [board[0][:], board[1][:], board[2][:]] = board

crates/ruff_linter/src/checkers/ast/analyze/statement.rs

@@ -13,6 +13,7 @@ use crate::rules::{
     flake8_pie, flake8_pyi, flake8_pytest_style, flake8_raise, flake8_return, flake8_simplify,
     flake8_slots, flake8_tidy_imports, flake8_type_checking, mccabe, pandas_vet, pep8_naming,
     perflint, pycodestyle, pyflakes, pygrep_hooks, pylint, pyupgrade, refurb, ruff, tryceratops,
+    wps_light,
 };
 use crate::settings::types::PythonVersion;
 
@@ -1650,6 +1651,9 @@ pub(crate) fn statement(stmt: &Stmt, checker: &mut Checker) {
             if checker.enabled(Rule::NonPEP695TypeAlias) {
                 pyupgrade::rules::non_pep695_type_alias_type(checker, assign);
             }
+            if checker.enabled(Rule::AssignmentToSubscriptSlice) {
+                wps_light::rules::assignment_to_subscript_slice(checker, assign);
+            }
         }
         Stmt::AnnAssign(
             assign_stmt @ ast::StmtAnnAssign {

crates/ruff_linter/src/codes.rs

@@ -933,6 +933,9 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Pydoclint, "501") => (RuleGroup::Preview, rules::pydoclint::rules::DocstringMissingException),
         (Pydoclint, "502") => (RuleGroup::Preview, rules::pydoclint::rules::DocstringExtraneousException),
 
+        // wps-light
+        (WpsLight, "362") => (RuleGroup::Preview, rules::wps_light::rules::AssignmentToSubscriptSlice),
+
         // ruff
         (Ruff, "001") => (RuleGroup::Stable, rules::ruff::rules::AmbiguousUnicodeCharacterString),
         (Ruff, "002") => (RuleGroup::Stable, rules::ruff::rules::AmbiguousUnicodeCharacterDocstring),

crates/ruff_linter/src/registry.rs

@@ -208,6 +208,9 @@ pub enum Linter {
     /// [pydoclint](https://pypi.org/project/pydoclint/)
     #[prefix = "DOC"]
     Pydoclint,
+    /// [wps-light](https://pypi.org/project/wps-light/)
+    #[prefix = "WPS"]
+    WpsLight,
     /// Ruff-specific rules
     #[prefix = "RUF"]
     Ruff,

crates/ruff_linter/src/rules/mod.rs

@@ -57,3 +57,4 @@ pub mod pyupgrade;
 pub mod refurb;
 pub mod ruff;
 pub mod tryceratops;
+pub mod wps_light;

crates/ruff_linter/src/rules/wps_light/mod.rs

@@ -0,0 +1,26 @@
+//! Rules from [wps-light](https://pypi.org/project/wps-light/).
+pub(crate) mod rules;
+
+#[cfg(test)]
+mod tests {
+    use std::convert::AsRef;
+    use std::path::Path;
+
+    use anyhow::Result;
+    use test_case::test_case;
+
+    use crate::registry::Rule;
+    use crate::test::test_path;
+    use crate::{assert_messages, settings};
+
+    #[test_case(Rule::AssignmentToSubscriptSlice, Path::new("WPS362.py"))]
+    fn rules(rule_code: Rule, path: &Path) -> Result<()> {
+        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let diagnostics = test_path(
+            Path::new("wps_light").join(path).as_path(),
+            &settings::LinterSettings::for_rule(rule_code),
+        )?;
+        assert_messages!(snapshot, diagnostics);
+        Ok(())
+    }
+}

crates/ruff_linter/src/rules/wps_light/rules/assignment_to_subscript_slice.rs

@@ -0,0 +1,72 @@
+use ruff_diagnostics::{Diagnostic, Violation};
+use ruff_macros::{derive_message_formats, violation};
+use ruff_python_ast::{Expr, StmtAssign};
+use ruff_text_size::Ranged;
+
+use crate::checkers::ast::Checker;
+
+/// ## What it does
+/// This rule checks for assignments to a subscript slice.
+///
+/// ## Why is this bad?
+/// Assignment to a slice can implicitly change the size of a list,
+/// leading to potential bugs that are difficult to spot.
+///
+/// ## Example
+/// ```python
+/// a[1:3] = [1, 2]
+/// a[slice(1)] = [1, 3]
+/// ```
+///
+/// Use instead:
+/// Instead of using slice assignment, modify individual elements to avoid implicit size changes and potential confusion:
+/// ```python
+/// a[5] = 1
+/// ```
+///
+/// ## Notes
+/// - A common example of this, which violates the rule, is in-place list replacement using `[:]`.
+/// This approach can replace the entire content of the list while maintaining the same object reference.
+/// - Slice assignment is only in-place replacement of multiple array elements.
+///
+/// ## References
+/// - [Python documentation: Assign](https://docs.python.org/3/library/ast.html#ast.Assign)
+#[violation]
+pub struct AssignmentToSubscriptSlice;
+
+impl Violation for AssignmentToSubscriptSlice {
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        "Assignment to a subscript slice found".to_string()
+    }
+}
+
+/// WPS362
+pub(crate) fn assignment_to_subscript_slice(checker: &mut Checker, stmt: &StmtAssign) {
+    let StmtAssign { targets, .. } = stmt;
+    targets
+        .iter()
+        .for_each(|target| check_subscript_slice(checker, target));
+}
+
+fn check_subscript_slice(checker: &mut Checker, expr: &Expr) {
+    match expr {
+        Expr::Subscript(expr_subscript) => {
+            if !expr_subscript.slice.is_slice_expr() {
+                return;
+            }
+            checker
+                .diagnostics
+                .push(Diagnostic::new(AssignmentToSubscriptSlice, expr.range()));
+        }
+        Expr::List(expr_list) => expr_list
+            .elts
+            .iter()
+            .for_each(|item| check_subscript_slice(checker, item)),
+        Expr::Tuple(expr_tuple) => expr_tuple
+            .elts
+            .iter()
+            .for_each(|item| check_subscript_slice(checker, item)),
+        _ => {}
+    }
+}

crates/ruff_linter/src/rules/wps_light/rules/mod.rs

@@ -0,0 +1,3 @@
+pub(crate) use assignment_to_subscript_slice::*;
+
+mod assignment_to_subscript_slice;

crates/ruff_linter/src/rules/wps_light/snapshots/ruff_linter__rules__wps_light__tests__assignment-to-subscript-slice_WPS362.py.snap

@@ -0,0 +1,100 @@
+---
+source: crates/ruff_linter/src/rules/wps_light/mod.rs
+snapshot_kind: text
+---
+WPS362.py:1:1: WPS362 Assignment to a subscript slice found
+  |
+1 | a[1:3] = [1, 2]
+  | ^^^^^^ WPS362
+2 | a[slice(1)] = [1, 3]
+  |
+
+WPS362.py:4:1: WPS362 Assignment to a subscript slice found
+  |
+2 | a[slice(1)] = [1, 3]
+3 | 
+4 | a[:0], a[-1:] = prefix, suffix
+  | ^^^^^ WPS362
+5 | 
+6 | a[:] = complete_replacement
+  |
+
+WPS362.py:4:8: WPS362 Assignment to a subscript slice found
+  |
+2 | a[slice(1)] = [1, 3]
+3 | 
+4 | a[:0], a[-1:] = prefix, suffix
+  |        ^^^^^^ WPS362
+5 | 
+6 | a[:] = complete_replacement
+  |
+
+WPS362.py:6:1: WPS362 Assignment to a subscript slice found
+  |
+4 | a[:0], a[-1:] = prefix, suffix
+5 | 
+6 | a[:] = complete_replacement
+  | ^^^^ WPS362
+7 | 
+8 | a[0:0] = prepend
+  |
+
+WPS362.py:8:1: WPS362 Assignment to a subscript slice found
+   |
+ 6 | a[:] = complete_replacement
+ 7 | 
+ 8 | a[0:0] = prepend
+   | ^^^^^^ WPS362
+ 9 | 
+10 | a[0] = 1
+   |
+
+WPS362.py:16:1: WPS362 Assignment to a subscript slice found
+   |
+14 | board = [["_"] * size for _ in range(size)]
+15 | 
+16 | board[0:1][1:2] = "X"
+   | ^^^^^^^^^^^^^^^ WPS362
+17 | 
+18 | board[0] = board[0:1] = board[1:2] = [board[0][:], board[1][:], board[2][:]] = board
+   |
+
+WPS362.py:18:12: WPS362 Assignment to a subscript slice found
+   |
+16 | board[0:1][1:2] = "X"
+17 | 
+18 | board[0] = board[0:1] = board[1:2] = [board[0][:], board[1][:], board[2][:]] = board
+   |            ^^^^^^^^^^ WPS362
+   |
+
+WPS362.py:18:25: WPS362 Assignment to a subscript slice found
+   |
+16 | board[0:1][1:2] = "X"
+17 | 
+18 | board[0] = board[0:1] = board[1:2] = [board[0][:], board[1][:], board[2][:]] = board
+   |                         ^^^^^^^^^^ WPS362
+   |
+
+WPS362.py:18:39: WPS362 Assignment to a subscript slice found
+   |
+16 | board[0:1][1:2] = "X"
+17 | 
+18 | board[0] = board[0:1] = board[1:2] = [board[0][:], board[1][:], board[2][:]] = board
+   |                                       ^^^^^^^^^^^ WPS362
+   |
+
+WPS362.py:18:52: WPS362 Assignment to a subscript slice found
+   |
+16 | board[0:1][1:2] = "X"
+17 | 
+18 | board[0] = board[0:1] = board[1:2] = [board[0][:], board[1][:], board[2][:]] = board
+   |                                                    ^^^^^^^^^^^ WPS362
+   |
+
+WPS362.py:18:65: WPS362 Assignment to a subscript slice found
+   |
+16 | board[0:1][1:2] = "X"
+17 | 
+18 | board[0] = board[0:1] = board[1:2] = [board[0][:], board[1][:], board[2][:]] = board
+   |                                                                 ^^^^^^^^^^^ WPS362
+   |