rust/tests/ui/comparison_chain.rs

#![allow(dead_code)]
#![warn(clippy::comparison_chain)]

fn a() {}
fn b() {}
fn c() {}

fn f(x: u8, y: u8, z: u8) {
    // Ignored: Only one branch
    if x > y {
        a()
    }

    if x > y {
        //~^ ERROR: `if` chain can be rewritten with `match`
        a()
    } else if x < y {
        b()
    }

    // Ignored: Only one explicit conditional
    if x > y {
        a()
    } else {
        b()
    }

    if x > y {
        //~^ ERROR: `if` chain can be rewritten with `match`
        a()
    } else if x < y {
        b()
    } else {
        c()
    }

    if x > y {
        //~^ ERROR: `if` chain can be rewritten with `match`
        a()
    } else if y > x {
        b()
    } else {
        c()
    }

    if x > 1 {
        //~^ ERROR: `if` chain can be rewritten with `match`
        a()
    } else if x < 1 {
        b()
    } else if x == 1 {
        c()
    }

    // Ignored: Binop args are not equivalent
    if x > 1 {
        a()
    } else if y > 1 {
        b()
    } else {
        c()
    }

    // Ignored: Binop args are not equivalent
    if x > y {
        a()
    } else if x > z {
        b()
    } else if y > z {
        c()
    }

    // Ignored: Not binary comparisons
    if true {
        a()
    } else if false {
        b()
    } else {
        c()
    }
}

#[allow(clippy::float_cmp)]
fn g(x: f64, y: f64, z: f64) {
    // Ignored: f64 doesn't implement Ord
    if x > y {
        a()
    } else if x < y {
        b()
    }

    // Ignored: f64 doesn't implement Ord
    if x > y {
        a()
    } else if x < y {
        b()
    } else {
        c()
    }

    // Ignored: f64 doesn't implement Ord
    if x > y {
        a()
    } else if y > x {
        b()
    } else {
        c()
    }

    // Ignored: f64 doesn't implement Ord
    if x > 1.0 {
        a()
    } else if x < 1.0 {
        b()
    } else if x == 1.0 {
        c()
    }
}

fn h<T: Ord>(x: T, y: T, z: T) {
    if x > y {
        //~^ ERROR: `if` chain can be rewritten with `match`
        a()
    } else if x < y {
        b()
    }

    if x > y {
        //~^ ERROR: `if` chain can be rewritten with `match`
        a()
    } else if x < y {
        b()
    } else {
        c()
    }

    if x > y {
        //~^ ERROR: `if` chain can be rewritten with `match`
        a()
    } else if y > x {
        b()
    } else {
        c()
    }
}

// The following uses should be ignored
mod issue_5212 {
    use super::{a, b, c};
    fn foo() -> u8 {
        21
    }

    fn same_operation_equals() {
        // operands are fixed

        if foo() == 42 {
            a()
        } else if foo() == 42 {
            b()
        }

        if foo() == 42 {
            a()
        } else if foo() == 42 {
            b()
        } else {
            c()
        }

        // operands are transposed

        if foo() == 42 {
            a()
        } else if 42 == foo() {
            b()
        }
    }

    fn same_operation_not_equals() {
        // operands are fixed

        if foo() > 42 {
            a()
        } else if foo() > 42 {
            b()
        }

        if foo() > 42 {
            a()
        } else if foo() > 42 {
            b()
        } else {
            c()
        }

        if foo() < 42 {
            a()
        } else if foo() < 42 {
            b()
        }

        if foo() < 42 {
            a()
        } else if foo() < 42 {
            b()
        } else {
            c()
        }
    }
}

enum Sign {
    Negative,
    Positive,
    Zero,
}

impl Sign {
    const fn sign_i8(n: i8) -> Self {
        if n == 0 {
            Sign::Zero
        } else if n > 0 {
            Sign::Positive
        } else {
            Sign::Negative
        }
    }
}

const fn sign_i8(n: i8) -> Sign {
    if n == 0 {
        Sign::Zero
    } else if n > 0 {
        Sign::Positive
    } else {
        Sign::Negative
    }
}

fn main() {}