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feat(linter): implement @typescript-eslint/no-dynamic-delete (#3971)
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kaykdm authored Jun 30, 2024
1 parent 10a3c9a commit 2114475
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2 changes: 2 additions & 0 deletions crates/oxc_linter/src/rules.rs
Original file line number Diff line number Diff line change
Expand Up @@ -131,6 +131,7 @@ mod typescript {
pub mod consistent_type_definitions;
pub mod explicit_function_return_type;
pub mod no_duplicate_enum_values;
pub mod no_dynamic_delete;
pub mod no_empty_interface;
pub mod no_explicit_any;
pub mod no_extra_non_null_assertion;
Expand Down Expand Up @@ -548,6 +549,7 @@ oxc_macros::declare_all_lint_rules! {
typescript::explicit_function_return_type,
typescript::no_non_null_assertion,
typescript::no_non_null_asserted_nullish_coalescing,
typescript::no_dynamic_delete,
jest::expect_expect,
jest::max_expects,
jest::max_nested_describe,
Expand Down
164 changes: 164 additions & 0 deletions crates/oxc_linter/src/rules/typescript/no_dynamic_delete.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,164 @@
use oxc_ast::{ast::Expression, AstKind};
use oxc_diagnostics::OxcDiagnostic;
use oxc_macros::declare_oxc_lint;
use oxc_span::Span;
use oxc_syntax::operator::UnaryOperator;

use crate::{context::LintContext, rule::Rule, AstNode};

#[derive(Debug, Default, Clone)]
pub struct NoDynamicDelete;

declare_oxc_lint!(
/// ### What it does
/// Disallow using the delete operator on computed key expressions.
///
/// ### Why is this bad?
/// Deleting dynamically computed keys can be dangerous and in some cases not well optimized.
/// Using the delete operator on keys that aren't runtime constants could be a sign that you're using the wrong data structures.
/// Consider using a Map or Set if you’re using an object as a key-value collection.
///
/// ### Example
/// ```javascript
/// const container: { [i: string]: 0 } = {};
/// delete container['aa' + 'b'];
/// ```
NoDynamicDelete,
restriction,
);

fn no_dynamic_delete_diagnostic(span0: Span) -> OxcDiagnostic {
OxcDiagnostic::warn(
"typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.",
)
.with_help("Disallow using the `delete` operator on computed key expressions")
.with_label(span0)
}

impl Rule for NoDynamicDelete {
fn run<'a>(&self, node: &AstNode<'a>, ctx: &LintContext<'a>) {
let AstKind::UnaryExpression(expr) = node.kind() else { return };
if !matches!(expr.operator, UnaryOperator::Delete) {
return;
}

let Expression::ComputedMemberExpression(computed_expr) = &expr.argument else { return };
let inner_expression = computed_expr.expression.get_inner_expression();
if inner_expression.is_string_literal() || inner_expression.is_number_literal() {
return;
}

if let Expression::UnaryExpression(unary_expr) = &inner_expression {
if unary_expr.operator == UnaryOperator::UnaryNegation
&& unary_expr.argument.is_number_literal()
{
return;
}
}
ctx.diagnostic(no_dynamic_delete_diagnostic(expr.span));
}
}

#[test]
fn test() {
use crate::tester::Tester;

let pass = vec![
"
const container: { [i: string]: 0 } = {};
delete container.aaa;
",
"
const container: { [i: string]: 0 } = {};
delete container.delete;
",
"
const container: { [i: string]: 0 } = {};
delete container[7];
",
"
const container: { [i: string]: 0 } = {};
delete container[-7];
",
"
const container: { [i: string]: 0 } = {};
delete container['-Infinity'];
",
"
const container: { [i: string]: 0 } = {};
delete container['+Infinity'];
",
"
const value = 1;
delete value;
",
"
const value = 1;
delete -value;
",
"
const container: { [i: string]: 0 } = {};
delete container['aaa'];
",
"
const container: { [i: string]: 0 } = {};
delete container['delete'];
",
"
const container: { [i: string]: 0 } = {};
delete container['NaN'];
",
"
const container = {};
delete container[('aaa')]
",
];

let fail = vec![
"
const container: { [i: string]: 0 } = {};
delete container['aa' + 'b'];
",
"
const container: { [i: string]: 0 } = {};
delete container[+7];
",
"
const container: { [i: string]: 0 } = {};
delete container[-Infinity];
",
"
const container: { [i: string]: 0 } = {};
delete container[+Infinity];
",
"
const container: { [i: string]: 0 } = {};
delete container[NaN];
",
"
const container: { [i: string]: 0 } = {};
const name = 'name';
delete container[name];
",
"
const container: { [i: string]: 0 } = {};
const getName = () => 'aaa';
delete container[getName()];
",
"
const container: { [i: string]: 0 } = {};
const name = { foo: { bar: 'bar' } };
delete container[name.foo.bar];
",
"
const container: { [i: string]: 0 } = {};
delete container[+'Infinity'];
",
"
const container: { [i: string]: 0 } = {};
delete container[typeof 1];
",
];

Tester::new(NoDynamicDelete::NAME, pass, fail).test_and_snapshot();
}
92 changes: 92 additions & 0 deletions crates/oxc_linter/src/snapshots/no_dynamic_delete.snap
Original file line number Diff line number Diff line change
@@ -0,0 +1,92 @@
---
source: crates/oxc_linter/src/tester.rs
---
typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.
╭─[no_dynamic_delete.tsx:3:10]
2const container: { [i: string]: 0 } = {};
3delete container['aa' + 'b'];
· ────────────────────────────
4
╰────
help: Disallow using the `delete` operator on computed key expressions

typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.
╭─[no_dynamic_delete.tsx:3:10]
2const container: { [i: string]: 0 } = {};
3delete container[+7];
· ────────────────────
4
╰────
help: Disallow using the `delete` operator on computed key expressions

typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.
╭─[no_dynamic_delete.tsx:3:10]
2const container: { [i: string]: 0 } = {};
3delete container[-Infinity];
· ───────────────────────────
4
╰────
help: Disallow using the `delete` operator on computed key expressions

typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.
╭─[no_dynamic_delete.tsx:3:10]
2const container: { [i: string]: 0 } = {};
3delete container[+Infinity];
· ───────────────────────────
4
╰────
help: Disallow using the `delete` operator on computed key expressions

typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.
╭─[no_dynamic_delete.tsx:3:10]
2const container: { [i: string]: 0 } = {};
3delete container[NaN];
· ─────────────────────
4
╰────
help: Disallow using the `delete` operator on computed key expressions

typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.
╭─[no_dynamic_delete.tsx:4:10]
3const name = 'name';
4delete container[name];
· ──────────────────────
5
╰────
help: Disallow using the `delete` operator on computed key expressions

typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.
╭─[no_dynamic_delete.tsx:4:10]
3const getName = () => 'aaa';
4delete container[getName()];
· ───────────────────────────
5
╰────
help: Disallow using the `delete` operator on computed key expressions

typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.
╭─[no_dynamic_delete.tsx:4:10]
3const name = { foo: { bar: 'bar' } };
4delete container[name.foo.bar];
· ──────────────────────────────
5
╰────
help: Disallow using the `delete` operator on computed key expressions

typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.
╭─[no_dynamic_delete.tsx:3:10]
2const container: { [i: string]: 0 } = {};
3delete container[+'Infinity'];
· ─────────────────────────────
4
╰────
help: Disallow using the `delete` operator on computed key expressions

typescript-eslint(no-dynamic-delete): Do not delete dynamically computed property keys.
╭─[no_dynamic_delete.tsx:3:10]
2const container: { [i: string]: 0 } = {};
3delete container[typeof 1];
· ──────────────────────────
4
╰────
help: Disallow using the `delete` operator on computed key expressions

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