rustScope errorMedium

Variable shadowing in match arm pattern binding

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BugFind the bug and fix the code

What it should do

Check if code matches target expected code. Example: match_expected_code(200, 200) -> true

What happens instead

Match arm unconditionally matches because variable name binds a new pattern instead of comparing

fn match_expected_code(actual: i32, expected: i32) -> bool {
    match actual {
        // 'expected' here binds a new local variable shadowing the parameter!
        expected => true,
        _ => false,
    }
}

fn main() {
    println!("{}", match_expected_code(404, 200));
}

Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).

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This bug belongs to the scope and closure bugs pattern

Every callback reports the last value, a counter never increments, UnboundLocalError on a variable you can see.

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fn match_expected_code(actual: i32, expected: i32) -> bool { match actual { // 'expected' here binds a new local variable shadowing the parameter! expected => true, _ => false, } } fn main() { println!("{}", match_expected_code(404, 200)); }

Variable shadowing in match arm pattern binding

What it should do

What happens instead

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Variable shadowing in match arm pattern binding

What it should do

What happens instead

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