codeql/rust/ql/test/library-tests/variables/main.rs

#![feature(let_chains)]
#![feature(if_let_guard)]
use std::ops::AddAssign;

fn print_str(s: &str) // s
{
    println!("{}", s); // $ read_access=s
}

fn print_i64(i: i64) // i
{
    println!("{}", i); // $ read_access=i
}

fn print_i64_ref(i: &i64) {
    print_i64(*i) // $ read_access=i
}

fn immutable_variable() {
    let x1 = "a"; // x1
    print_str(x1); // $ read_access=x1
}

fn mutable_variable() {
    let mut x2 = 4; // x2
    print_i64(x2); // $ read_access=x2
    x2 = 5; // $ write_access=x2
    print_i64(x2); // $ read_access=x2
    x2 = x2; // $ read_access=x2 $ write_access=x2
    print_i64(x2); // $ read_access=x2
}

fn mutable_variable_immutable_borrow() {
    let mut x = 1;
    print_i64_ref(&x); // $ access=x
    x = 2; // $ write_access=x
    print_i64_ref(&x); // $ access=x
}

fn variable_shadow1() {
    let x3 = 1; // x3_1
    print_i64(x3); // $ read_access=x3_1
    let x3 = // x3_2
        x3 + 1; // $ read_access=x3_1
    print_i64(x3); // $ read_access=x3_2
}

fn variable_shadow2() {
    let x4 = "a"; // x4_1
    print_str(x4); // $ read_access=x4_1
    {
        let x4 = "b"; // x4_2
        print_str(x4); // $ read_access=x4_2
    }
    print_str(x4); // $ read_access=x4_1
}

struct Point<'a> {
    x: &'a str,
    y: &'a str,
}

fn let_pattern1() {
    let (
        (
            a1, // a1
            b1, // b1
        ),
        Point {
            x, // x
            y, // y
        },
    ) = (("a", "b"), Point { x: "x", y: "y" });
    print_str(a1); // $ read_access=a1
    print_str(b1); // $ read_access=b1
    print_str(x); // $ read_access=x
    print_str(y); // $ read_access=y
}

fn let_pattern2() {
    let p1 = Point { x: "a", y: "b" }; // p1
    let Point {
        x: a2, // a2
        y: b2, // b2
    } = p1; // $ read_access=p1
    print_str(a2); // $ read_access=a2
    print_str(b2); // $ read_access=b2
}

fn let_pattern3() {
    let s1 = Some(String::from("Hello!")); // s1

    if let Some(ref s2) // s2
        = s1 { // $ read_access=s1
        print_str(s2); // $ read_access=s2
    }
}

fn let_pattern4() {
    let x = Some("x5"); // x1
    let Some(x): Option<&str> // x2
    = x // $ read_access=x1
    else {
        let x = // x3
            x; // $ read_access=x1
        print_str(x.unwrap()); // $ read_access=x3
        todo!()
    };
    print_str(x); // $ read_access=x2
}

fn let_pattern5() {
    let s1 = Some(String::from("Hello!")); // s1

    while let Some(ref s2) // s2
        = s1 { // $ read_access=s1
        print_str(s2); // $ read_access=s2
    }
}

fn match_pattern1() {
    let x6 = Some(5); // x6
    let y1 = 10; // y1_1

    match x6 { // $ read_access=x6
        Some(50) => print_str("Got 50"),
        Some(y1) // y1_2
        =>
        {
            print_i64(y1)// $ read_access=y1_2
        }
        None => print_str("NONE"),
    }

    print_i64(y1); // $ read_access=y1_1
}

fn match_pattern2() {
    let numbers = (2, 4, 8, 16, 32); // numbers

    match numbers // $ read_access=numbers
    {
        (
            first, // first
            _,
            third, // third
            _,
            fifth, // fifth
        ) => {
            print_i64(first); // $ read_access=first
            print_i64(third); // $ read_access=third
            print_i64(fifth); // $ read_access=fifth
        }
    }

    match numbers // $ read_access=numbers
    {
        (
            first, // first
            ..,
            last, // last
        ) => {
            print_i64(first); // $ read_access=first
            print_i64(last); // $ read_access=last
        }
    }
}

fn match_pattern3() {
    let p2 = Point { x: "x", y: "y" }; // p2

    match p2 { // $ read_access=p2
        Point {
            x: x7, .. // x7
        } => print_str(x7), // $ read_access=x7
    }
}

enum Message {
    Hello { id: i64 },
}

fn match_pattern4() {
    let msg = Message::Hello { id: 0 }; // msg

    match msg // $ read_access=msg
    {
        Message::Hello {
            id: id_variable @ 3..=7, // id_variable
        } => print_i64(id_variable), // $ read_access=id_variable
        Message::Hello { id: 10..=12 } => {
            println!("Found an id in another range")
        }
        Message::Hello { id } // id
        =>
        {
            print_i64(id) // $ read_access=id
        }
    }
}

enum Either {
    Left(i64),
    Right(i64),
}

fn match_pattern5() {
    let either = Either::Left(32); // either
    match either { // $ read_access=either
        Either::Left(a3) | Either::Right(a3) // a3
            => print_i64(a3), // $ read_access=a3
    }
}

enum ThreeValued {
    First(i64),
    Second(i64),
    Third(i64),
}

fn match_pattern6() {
    let tv = ThreeValued::Second(62); // tv
    match tv { // $ read_access=tv
        ThreeValued::First(a4) | ThreeValued::Second(a4) | ThreeValued::Third(a4) // a4
            => print_i64(a4), // $ read_access=a4
    }
    match tv { // $ read_access=tv
        (ThreeValued::First(a5) | ThreeValued::Second(a5)) | ThreeValued::Third(a5) // a5
            => print_i64(a5), // $ read_access=a5
    }
    match tv { // $ read_access=tv
        ThreeValued::First(a6) | (ThreeValued::Second(a6) | ThreeValued::Third(a6)) // a6
            => print_i64(a6), // $ read_access=a6
    }
}

fn match_pattern7() {
    let either = Either::Left(32); // either
    match either { // $ read_access=either
        Either::Left(a7) | Either::Right(a7) // a7
            if a7 > 0 // $ read_access=a7
            => print_i64(a7), // $ read_access=a7
        _ => (),
    }
}

fn match_pattern8() {
    let either = Either::Left(32); // either

    match either { // $ read_access=either
        ref e @ // e
            (Either::Left(a11) | Either::Right(a11)) // a11
        => {
            print_i64(a11); // $ read_access=a11
            if let Either::Left(a12) // a12
            = e { // $ read_access=e
                print_i64(*a12); // $ read_access=a12
            }
        }
        _ => (),
    }
}

enum FourValued {
    First(i64),
    Second(i64),
    Third(i64),
    Fourth(i64),
}

fn match_pattern9() {
    let fv = FourValued::Second(62); // tv
    match fv { // $ read_access=tv
        FourValued::First(a13) | (FourValued::Second(a13) | FourValued::Third(a13)) | FourValued::Fourth(a13) // a13
            => print_i64(a13), // $ read_access=a13
    }
}

#[rustfmt::skip]
fn match_pattern10() {
    let x= Some(42); // x1
    if let Some(x) // x2
    = x // $ read_access=x1
    &&
    x > 0 // $ read_access=x2
    {    
        print_i64(x); // $ read_access=x2
    } else {
        let x = // x3
            x; // $ read_access=x1
        print_i64(x.unwrap()); // $ read_access=x3
    }
}

#[rustfmt::skip]
fn match_pattern11() {
    let x = Some(42); // x1
    if let Some(x) // x2
    = x // $ read_access=x1
    &&
    let Some(x) // x3
    = Some(x) // $ read_access=x2
    &&
    x > 0 // $ read_access=x3
    {    
        print_i64(x); // $ read_access=x3
    } else {
        let x = // x4
            x; // $ read_access=x1
        print_i64(x.unwrap()); // $ read_access=x4
    }
}

#[rustfmt::skip]
fn match_pattern12() {
    let x = Some(42); // x1
    while let Some(x) // x2
    = x // $ read_access=x1
    &&
    let Some(x) // x3
    = Some(x) // $ read_access=x2
    &&
    x > 0 // $ read_access=x3
    {    
        print_i64(x); // $ read_access=x3
        break;
    }

    print_i64(x.unwrap()); // $ read_access=x1
}

#[rustfmt::skip]
fn match_pattern13() {
    let x = Some(42); // x1
    match x { // $ read_access=x1
        Some(x) // x2
            if let x // x3
               = x // $ read_access=x2
               && x > 0 => (), // $ read_access=x3
        _ => ()
    }

    print_i64(x.unwrap()); // $ read_access=x1
}

#[rustfmt::skip]
fn match_pattern14() {
    let x = Ok(42); // x1
    if let Err(x) // x2
    = x // $ read_access=x1
    {
        print_i64(x); // $ read_access=x2
    }
    else if let Ok(x) // x3
    = x // $ read_access=x1
    {    
        print_i64(x); // $ read_access=x3
    } else {
        print_i64(x.unwrap()); // $ read_access=x1
    }
}

fn match_pattern15() {
    let x = Some(0); // x1
    match x { // $ read_access=x1
            Some(x) // x2
                => x, // $ read_access=x2
            _ => 0
        };
}

fn param_pattern1(
    a8: &str, // a8
    (
        b3, // b3
        c1, // c1
    ): (&str, &str),
) -> () {
    print_str(a8); // $ read_access=a8
    print_str(b3); // $ read_access=b3
    print_str(c1); // $ read_access=c1
}

fn param_pattern2((Either::Left(a9) | Either::Right(a9)): Either, // a9
) -> () {
    print_i64(a9); // $ read_access=a9
}

fn destruct_assignment() {
    let (
        mut a10, // a10
        mut b4,  // b4
        mut c2,  // c2
    ) = (1, 2, 3);
    print_i64(a10); // $ read_access=a10
    print_i64(b4); // $ read_access=b4
    print_i64(c2); // $ read_access=c2

    (
        c2,  // $ write_access=c2
        b4,  // $ write_access=b4
        a10, // $ write_access=a10
    ) = (
        a10, // $ read_access=a10
        b4,  // $ read_access=b4
        c2,  // $ read_access=c2
    );
    print_i64(a10); // $ read_access=a10
    print_i64(b4); // $ read_access=b4
    print_i64(c2); // $ read_access=c2

    match (4, 5) {
        (
            a10, // a10_2
            b4,  // b4
        ) => {
            print_i64(a10); // $ read_access=a10_2
            print_i64(b4); // $ read_access=b4
        }
    }

    print_i64(a10); // $ read_access=a10
    print_i64(b4); // $ read_access=b4
}

fn closure_variable() {
    let example_closure = // example_closure
        |x: i64| // x_1
        x; // $ read_access=x_1
    let n1 = // n1
        example_closure(5); // $ read_access=example_closure
    print_i64(n1); // $ read_access=n1

    immutable_variable();
    let immutable_variable = // immutable_variable
    |x: i64| // x_2
        x; // $ read_access=x_2
    let n2 = // n2
        immutable_variable(6); // $ read_access=immutable_variable
    print_i64(n2); // $ read_access=n2
}

fn nested_function() {
    // local variables shadow local functions
    let f = // f1
        |x: i64| // x_1
        x; // $ read_access=x_1
    print_i64(f(1)); // $ read_access=f1

    fn f(x: i64) -> i64 // x_2
    {
        x + 1 // $ read_access=x_2
    }

    print_i64(f(2)); // $ read_access=f1

    {
        print_i64(f(3));
        fn f(x: i64) -> i64 // x_3
        {
            2 * x // $ read_access=x_3
        }

        {
            print_i64(f(4));
        }

        let f = // f2
            |x: i64| // x_4
            x; // $ read_access=x_4
        print_i64(f(5)); // $ read_access=f2
    }
}

fn for_variable() {
    let v = &["apples", "cake", "coffee"]; // v

    for text // text
        in v { // $ read_access=v
        print_str(text); // $ read_access=text
    }
}

fn add_assign() {
    let mut a = 0; // a
    a += 1; // $ access=a
    print_i64(a); // $ read_access=a
    (&mut a).add_assign(10); // $ access=a
    print_i64(a); // $ read_access=a
}

fn mutate() {
    let mut i = 1; // i
    let ref_i = // ref_i
        &mut i; // $ access=i
    *ref_i = 2; // $ read_access=ref_i
    print_i64(i); // $ read_access=i
}

fn mutate_param(x: &mut i64) -> &mut i64 {
    *x = // $ read_access=x
        *x + // $ read_access=x
        *x; // $ read_access=x
    return x; // $ read_access=x
}

fn mutate_param2<'a>(x: &'a mut i64, y: &mut &'a mut i64) {
    *x = // $ read_access=x
        *x + // $ read_access=x
        *x; // $ read_access=x
    *y = // $ read_access=y
        x; // $ read_access=x
}

fn mutate_arg() {
    let mut x = 2; // x
    let y = // y
        mutate_param(&mut x); // $ access=x
    *y = 10; // $ read_access=y

    // prints 10, not 4
    print_i64(x); // $ read_access=x

    let mut z = 4; // z
    let w = // w
        &mut &mut x; // $ access=x
    mutate_param2(
        &mut z, // $ access=z
        w,      // $ read_access=w
    );
    **w = 11; // $ read_access=w

    // prints 11, not 8
    print_i64(z); // $ read_access=z
}

fn alias() {
    let mut x = 1; // x
    let y = // y
        &mut x; // $ access=x
    *y = 2; // $ read_access=y
    print_i64(x); // $ read_access=x
}

fn capture_immut() {
    let x = 100; // x

    // Captures immutable value by immutable reference
    let cap = || {
        print_i64(x); // $ read_access=x
    };
    cap(); // $ read_access=cap
    print_i64(x); // $ read_access=x
}

fn capture_mut() {
    let mut x = 1; // x

    // Captures mutable value by immutable reference
    let closure1 = || {
        print_i64(x); // $ read_access=x
    };
    closure1(); // $ read_access=closure1
    print_i64(x); // $ read_access=x

    let mut y = 2; // y

    // Captures mutable value by mutable reference
    let mut closure2 = || {
        y = 3; // $ write_access=y
    };
    closure2(); // $ read_access=closure2
    print_i64(y); // $ read_access=y

    let mut z = 2; // z

    // Captures mutable value by mutable reference and calls mutating method
    let mut closure3 = || {
        z.add_assign(1); // $ read_access=z
    };
    closure3(); // $ read_access=closure3
    print_i64(z); // $ read_access=z
}

async fn async_block_capture() {
    let mut i: i64 = 0; // i
    let block = async {
        i = 1; // $ write_access=i
    };
    // The await below causes write to `i`
    block.await; // $ read_access=block
    print_i64(i); // $ read_access=i
}

fn phi(b: bool) {
    let mut x = 1; // x
    print_i64(x); // $ read_access=x
    print_i64(x + 1); // $ read_access=x
    #[rustfmt::skip]
    let _ = if b // $ read_access=b
    {
        x = 2; // $ write_access=x
        print_i64(x); // $ read_access=x
        print_i64(x + 1); // $ read_access=x
    } else {
        x = 3; // $ write_access=x
        print_i64(x); // $ read_access=x
        print_i64(x + 1); // $ read_access=x
    };
    print_i64(x); // $ read_access=x
}

fn phi_read(b1: bool, b2: bool) {
    let x = 1; // x
    #[rustfmt::skip]
    let _ = if b1 // $ read_access=b1
    {
        print_i64(x); // $ read_access=x
    } else {
        print_i64(x); // $ read_access=x
    };

    #[rustfmt::skip]
    let _ = if b2 // $ read_access=b2
    {
        print_i64(x); // $ read_access=x
    } else {
        print_i64(x); // $ read_access=x
    };
}

struct MyStruct {
    val: i64,
}

impl MyStruct {
    fn my_get(&mut self) -> i64 {
        return self.val; // $ read_access=self
    }

    fn id(self) -> Self {
        self // $ read_access=self
    }

    fn my_method(&mut self) {
        let mut f = |n| {
            // Capture of `self`
            self.val += n; // $ read_access=self read_access=n
        };
        f(3); // $ read_access=f
        f(4); // $ read_access=f
    }
}

fn structs() {
    let mut a = MyStruct { val: 1 }; // a
    print_i64(a.my_get()); // $ read_access=a
    a.val = 5; // $ read_access=a
    print_i64(a.my_get()); // $ read_access=a
    a = MyStruct { val: 2 }; // $ write_access=a
    print_i64(a.my_get()); // $ read_access=a
}

fn arrays() {
    let mut a = [1, 2, 3]; // a
    print_i64(a[0]); // $ read_access=a
    a[1] = 5; // $ read_access=a
    print_i64(a[1]); // $ read_access=a
    a = [4, 5, 6]; // $ write_access=a
    print_i64(a[2]); // $ read_access=a
}

fn ref_arg() {
    let x = 16; // x
    print_i64_ref(&x); // $ access=x
    print_i64(x); // $ read_access=x

    let z = 17; // z
    print_i64_ref(&z); // $ access=z
}

trait Bar {
    fn bar(&self);
}

impl MyStruct {
    fn bar(&mut self) {
        *self = MyStruct { val: 3 }; // $ read_access=self
    }
}

fn ref_methodcall_receiver() {
    let mut a = MyStruct { val: 1 }; // a
    a.bar(); // $ read_access=a

    // prints 3, not 1
    print_i64(a.val); // $ read_access=a
}

macro_rules! let_in_macro {
    ($e:expr) => {{
        let var_in_macro = $e;
        var_in_macro
    }};
}

macro_rules! let_in_macro2 {
    ($e:expr) => {{
        let var_in_macro = 0;
        $e
    }};
}

fn macro_invocation() {
    let var_from_macro = // var_from_macro1
        let_in_macro!(37); // $ read_access=var_in_macro
    print_i64(var_from_macro); // $ read_access=var_from_macro1
    let var_in_macro = 33; // var_in_macro1

    // Our analysis does not currently respect the hygiene rules of Rust macros
    // (https://veykril.github.io/tlborm/decl-macros/minutiae/hygiene.html), because
    // all we have access to is the expanded AST
    print_i64(let_in_macro2!(var_in_macro)); // $ MISSING: read_access=var_in_macro1 $ SPURIOUS: read_access=var_in_macro
    print_i64(var_in_macro); // $ read_access=var_in_macro1
}

fn let_without_initializer() {
    let x; // x
    x = 1; // $ write_access=x
    print_i64(x); // $ read_access=x
}

fn capture_phi() {
    let mut x = 100; // x
    let mut cap = |b: bool| {
        #[rustfmt::skip]
        let _ = if b { // $ read_access=b
            x = 200; // $ write_access=x
        };
    };
    cap(true); // $ read_access=cap
    print_i64(x); // $ read_access=x
}

fn main() {
    immutable_variable();
    mutable_variable();
    mutable_variable_immutable_borrow();
    variable_shadow1();
    variable_shadow2();
    let_pattern1();
    let_pattern2();
    let_pattern3();
    let_pattern4();
    match_pattern1();
    match_pattern2();
    match_pattern3();
    match_pattern4();
    match_pattern5();
    match_pattern6();
    match_pattern7();
    match_pattern8();
    match_pattern9();
    match_pattern10();
    match_pattern11();
    match_pattern12();
    match_pattern13();
    match_pattern14();
    match_pattern15();
    param_pattern1("a", ("b", "c"));
    param_pattern2(Either::Left(45));
    destruct_assignment();
    closure_variable();
    nested_function();
    for_variable();
    add_assign();
    mutate();
    mutate_arg();
    alias();
    capture_mut();
    capture_immut();
    async_block_capture();
    structs();
    ref_arg();
    ref_methodcall_receiver();
    macro_invocation();
    capture_phi();
}