zeroize 1.8.1

Securely clear secrets from memory with a simple trait built on stable Rust primitives which guarantee memory is zeroed using an operation will not be 'optimized away' by the compiler. Uses a portable pure Rust implementation that works everywhere, even WASM!
Documentation
//! Integration tests for `zeroize_derive` proc macros

#![cfg(feature = "zeroize_derive")]

use zeroize::{Zeroize, ZeroizeOnDrop};

#[test]
fn derive_tuple_struct_test() {
    #[derive(Zeroize, ZeroizeOnDrop)]
    struct Z([u8; 3]);

    let mut value = Z([1, 2, 3]);
    value.zeroize();
    assert_eq!(&value.0, &[0, 0, 0])
}

#[test]
#[cfg(feature = "alloc")]
fn derive_struct_test() {
    #[derive(Zeroize, ZeroizeOnDrop)]
    struct Z {
        string: String,
        vec: Vec<u8>,
        bytearray: [u8; 3],
        number: usize,
        boolean: bool,
    }

    let mut value = Z {
        string: String::from("Hello, world!"),
        vec: vec![1, 2, 3],
        bytearray: [4, 5, 6],
        number: 42,
        boolean: true,
    };

    value.zeroize();

    assert!(value.string.is_empty());
    assert!(value.vec.is_empty());
    assert_eq!(&value.bytearray, &[0, 0, 0]);
    assert_eq!(value.number, 0);
    assert!(!value.boolean);
}

#[test]
fn derive_enum_test() {
    #[derive(Zeroize, ZeroizeOnDrop)]
    enum Z {
        #[allow(dead_code)]
        Variant1,
        Variant2(usize),
    }

    let mut value = Z::Variant2(26);

    value.zeroize();

    assert!(matches!(value, Z::Variant2(0)));
}

/// Test that the custom macro actually derived `Drop` for `Z`
#[test]
fn derive_struct_drop() {
    #[derive(Zeroize, ZeroizeOnDrop)]
    struct Z([u8; 3]);

    assert!(std::mem::needs_drop::<Z>());
}

/// Test that the custom macro actually derived `Drop` for `Z`
#[test]
fn derive_enum_drop() {
    #[allow(dead_code)]
    #[derive(Zeroize, ZeroizeOnDrop)]
    enum Z {
        Variant1,
        Variant2(usize),
    }

    assert!(std::mem::needs_drop::<Z>());
}

/// Test that the custom macro actually derived `Drop` for `Z`
#[test]
fn derive_struct_only_drop() {
    #[derive(ZeroizeOnDrop)]
    struct Z([u8; 3]);

    assert!(std::mem::needs_drop::<Z>());
}

/// Test that the custom macro actually derived `Drop` for `Z`
#[test]
fn derive_enum_only_drop() {
    #[allow(dead_code)]
    #[derive(ZeroizeOnDrop)]
    enum Z {
        Variant1,
        Variant2(usize),
    }

    assert!(std::mem::needs_drop::<Z>());
}

/// Test that `Drop` is not derived in the following case by defining a
/// `Drop` impl which should conflict if the custom derive defined one too
#[allow(dead_code)]
#[derive(Zeroize)]
struct ZeroizeNoDropStruct([u8; 3]);

impl Drop for ZeroizeNoDropStruct {
    fn drop(&mut self) {}
}

#[allow(dead_code)]
#[derive(Zeroize)]
enum ZeroizeNoDropEnum {
    Variant([u8; 3]),
}

impl Drop for ZeroizeNoDropEnum {
    fn drop(&mut self) {}
}

#[test]
#[cfg(feature = "alloc")]
fn derive_struct_skip() {
    #[derive(Zeroize, ZeroizeOnDrop)]
    struct Z {
        string: String,
        vec: Vec<u8>,
        #[zeroize(skip)]
        bytearray: [u8; 3],
        number: usize,
        boolean: bool,
    }

    let mut value = Z {
        string: String::from("Hello, world!"),
        vec: vec![1, 2, 3],
        bytearray: [4, 5, 6],
        number: 42,
        boolean: true,
    };

    value.zeroize();

    assert!(value.string.is_empty());
    assert!(value.vec.is_empty());
    assert_eq!(&value.bytearray, &[4, 5, 6]);
    assert_eq!(value.number, 0);
    assert!(!value.boolean);
}

#[test]
#[cfg(feature = "alloc")]
fn derive_enum_skip() {
    #[derive(Zeroize, ZeroizeOnDrop)]
    enum Z {
        #[allow(dead_code)]
        Variant1,
        #[zeroize(skip)]
        Variant2([u8; 3]),
        #[zeroize(skip)]
        Variant3 {
            string: String,
            vec: Vec<u8>,
            bytearray: [u8; 3],
            number: usize,
            boolean: bool,
        },
        Variant4 {
            string: String,
            vec: Vec<u8>,
            #[zeroize(skip)]
            bytearray: [u8; 3],
            number: usize,
            boolean: bool,
        },
    }

    let mut value = Z::Variant2([4, 5, 6]);

    value.zeroize();

    assert!(matches!(&value, Z::Variant2([4, 5, 6])));

    let mut value = Z::Variant3 {
        string: String::from("Hello, world!"),
        vec: vec![1, 2, 3],
        bytearray: [4, 5, 6],
        number: 42,
        boolean: true,
    };

    value.zeroize();

    assert!(matches!(
        &value,
        Z::Variant3 { string, vec, bytearray, number, boolean }
        if string == "Hello, world!" &&
            vec == &[1, 2, 3] &&
            bytearray == &[4, 5, 6] &&
            *number == 42 &&
            *boolean
    ));

    let mut value = Z::Variant4 {
        string: String::from("Hello, world!"),
        vec: vec![1, 2, 3],
        bytearray: [4, 5, 6],
        number: 42,
        boolean: true,
    };

    value.zeroize();

    assert!(matches!(
        &value,
        Z::Variant4 { string, vec, bytearray, number, boolean }
        if string.is_empty() &&
            vec.is_empty() &&
            bytearray == &[4, 5, 6] &&
            *number == 0 &&
            !boolean
    ));
}

#[test]
fn derive_bound() {
    trait T: Zeroize {}

    impl T for u8 {}

    #[derive(Zeroize)]
    #[zeroize(bound = "X: T")]
    struct Z<X>(X);

    let mut value = Z(5_u8);

    value.zeroize();

    assert_eq!(value.0, 0);
}

#[test]
fn derive_inherit_zeroize_on_drop() {
    #[derive(ZeroizeOnDrop)]
    struct X([u8; 3]);

    #[derive(ZeroizeOnDrop)]
    struct Z(X);

    let mut value = Z(X([1, 2, 3]));
    unsafe {
        std::ptr::drop_in_place(&mut value);
    }
    assert_eq!(&value.0 .0, &[0, 0, 0])
}

#[test]
fn derive_inherit_from_both() {
    #[derive(Zeroize, ZeroizeOnDrop)]
    struct X([u8; 3]);

    #[derive(ZeroizeOnDrop)]
    struct Z(X);

    let mut value = Z(X([1, 2, 3]));
    unsafe {
        std::ptr::drop_in_place(&mut value);
    }
    assert_eq!(&value.0 .0, &[0, 0, 0])
}

#[test]
fn derive_inherit_both() {
    #[derive(Zeroize, ZeroizeOnDrop)]
    struct X([u8; 3]);

    #[derive(Zeroize, ZeroizeOnDrop)]
    struct Z(X);

    let mut value = Z(X([1, 2, 3]));
    unsafe {
        std::ptr::drop_in_place(&mut value);
    }
    assert_eq!(&value.0 .0, &[0, 0, 0])
}

#[test]
fn derive_deref() {
    struct X([u8; 3]);

    impl std::ops::Deref for X {
        type Target = [u8];

        fn deref(&self) -> &Self::Target {
            &self.0
        }
    }

    impl std::ops::DerefMut for X {
        fn deref_mut(&mut self) -> &mut Self::Target {
            &mut self.0
        }
    }

    #[derive(Zeroize, ZeroizeOnDrop)]
    struct Z(X);

    let mut value = Z(X([1, 2, 3]));
    unsafe {
        std::ptr::drop_in_place(&mut value);
    }
    assert_eq!(&value.0 .0, &[0, 0, 0])
}

#[test]
#[cfg(feature = "alloc")]
#[allow(dead_code)]
fn derive_zeroize_on_drop_generic() {
    #[derive(ZeroizeOnDrop)]
    struct Y<T: Zeroize>(Box<T>);

    #[derive(ZeroizeOnDrop)]
    struct Z<T: Zeroize>(Vec<T>);
}

#[test]
#[allow(dead_code)]
fn derive_zeroize_unused_param() {
    #[derive(Zeroize)]
    struct Z<T> {
        arr: [u32; 5],
        #[zeroize(skip)]
        skipped: T,
    }
}

#[test]
#[allow(dead_code)]
// Issue #878
fn derive_zeroize_with_marker() {
    #[derive(ZeroizeOnDrop, Zeroize)]
    struct Test<A: Marker> {
        #[zeroize(skip)]
        field: Option<A>,
    }

    #[allow(dead_code)]
    trait Secret: ZeroizeOnDrop + Zeroize {}

    impl<A: Marker> Secret for Test<A> {}

    trait Marker {}
}

#[test]
#[allow(dead_code)]
// Issue #878
fn derive_zeroize_used_param() {
    #[derive(Zeroize)]
    struct Z<T> {
        used: T,
    }
}