Negative coverage: borrow_check_statement / let / premise borrow_check_expr_has_ty(env, assumptions, state, expr, ty, LiveBefore::live_before(&Assignment(id), env, &state, &places_live_on_exit), ) => state

Premise at line 189. Observed failure causes: failed_judgment.

36 tests failed proving this premise:

Source location: src/test_util.rs:464 (all coverage from this test)

#[test]
fn borrowck_err_checks_rustc_err_once() {
    let before = rustc_runs();
    FormalityTest::new(MOVED)
        .rustc_err(expect_test::expect![[r#"
            error[E0382]: use of moved value: `x`
             --> lib.rs
              |
            6 |     let mut x: Datum = Datum { value: 0_u32 };
              |         ----- move occurs because `x` has type `Datum`, which does not implement the `Copy` trait
            7 |     let mut y: Datum = x;
              |                        - value moved here
            8 |     let mut z: Datum = x;
              |                        ^ value used here after move
              |
            note: if `Datum` implemented `Clone`, you could clone the value
             --> lib.rs
              |
            1 | pub struct Datum {
              | ^^^^^^^^^^^^^^^^ consider implementing `Clone` for this type
            ...
            7 |     let mut y: Datum = x;
              |                        - you could clone this value

            For more information about this error, try `rustc --explain E0382`.
            error: could not compile `Foo` (lib) due to 1 previous error
        "#]])
        .borrowck_err(BorrowCheckFailure::All, expect_test::expect![[r#"
            the rule "access_permitted" at (nll.rs) failed because
              condition evaluated to false: `match access.kind
              {
                  AccessKind::Write =>
                  check_place_writable(&state, &access.place.to_place_expression()),
                  AccessKind::Read | AccessKind::Move =>
                  check_place_initialized(&state, &access.place.to_place_expression()),
              }`"#]]);
    assert_eq!(rustc_runs() - before, 1);
}

Source location: src/test_util.rs:479 (all coverage from this test)

#[test]
#[should_panic(expected = "expected `rustc` to succeed but it failed")]
fn borrowck_err_enforces_rustc_ok() {
    FormalityTest::new(MOVED).rustc_ok().borrowck_err(
        BorrowCheckFailure::All,
        expect_test::expect![[r#"
            the rule "access_permitted" at (nll.rs) failed because
              condition evaluated to false: `match access.kind
              {
                  AccessKind::Write =>
                  check_place_writable(&state, &access.place.to_place_expression()),
                  AccessKind::Read | AccessKind::Move =>
                  check_place_initialized(&state, &access.place.to_place_expression()),
              }`"#]],
    );
}

Source location: src/test_util.rs:516 (all coverage from this test)

#[test]
fn rustc_expectation_is_independent_of_borrowck_modes() {
    let before = rustc_runs();
    FormalityTest::new(NLL_ONLY_ERROR)
        .rustc_err(expect_test::expect![[r#"
            error[E0499]: cannot borrow `*m` as mutable more than once at a time
             --> lib.rs
              |
            3 | pub fn foo<'a00>(mut m: &'a00 mut Map) -> &'a00 mut Map {
              |            ---- lifetime `'a00` defined here
            4 |     {
            5 |         let mut n: &'_ mut Map = &mut *m;
              |                                  ------- first mutable borrow occurs here
            6 |         if false {
            7 |             return n;
              |                    - returning this value requires that `*m` is borrowed for `'a00`
            8 |         } else {
            9 |             let mut o: &'_ mut Map = &mut *m;
              |                                      ^^^^^^^ second mutable borrow occurs here

            For more information about this error, try `rustc --explain E0499`.
            error: could not compile `Foo` (lib) due to 1 previous error
        "#]])
        .borrowck_err(BorrowCheckFailure::Nll, expect_test::expect![[r#"
            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(m : &!lt_1 mut Map) : <&!lt_1 mut Map as Derefable>::Target
                &access.place = *(m : &!lt_1 mut Map) : <&!lt_1 mut Map as Derefable>::Target

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {!lt_1, ?lt_2, ?lt_3}
                &lifetime.upcast() = !lt_1

            the rule "loan_not_required_by_universal_regions" at (nll.rs) failed because
              condition evaluated to false: `outlived_by_loan.iter().all(|p| match p
              {
                  Parameter::Ty(_) => false, Parameter::Lt(lt) => match lt.as_ref()
                  {
                      Lt::Static => false, Lt::Variable(Variable::UniversalVar(_)) => false,
                      Lt::Variable(Variable::ExistentialVar(_)) => true,
                      Lt::Variable(Variable::BoundVar(_)) =>
                      panic!("cannot outlive a bound var"), Lt::Erased => true,
                  }, Parameter::Const(_) => panic!("cannot outlive a constant"),
              })`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `m`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(m : &!lt_1 mut Map) : <&!lt_1 mut Map as Derefable>::Target
                place_loaned_ref = m : &!lt_1 mut Map"#]]);
    assert_eq!(rustc_runs() - before, 1);
}

Source location: tests/borrowck.rs:172 (all coverage from this test)

fn foo() -> Datum {
    let x: Datum = Datum { value: 0_u32 };
    let y: Datum = x;
    let z: Datum = x;
    return z;
}

Source location: tests/borrowck.rs:393 (all coverage from this test)

fn foo() -> Datum {
    let x: Datum = Datum { value: 0_u32 };
    if true {
        let y: Datum = x;
    }
    let z: Datum = x;
    return z;
}

Source location: tests/borrowck.rs:532 (all coverage from this test)

fn foo() -> u32 {
    let x: Pair = Pair {
        first: Datum { value: 1_u32 },
        second: Datum { value: 2_u32 },
    };
    let a: Datum = x.first;
    let b: Pair = x;
    return 0_u32;
}

Source location: tests/borrowck.rs:580 (all coverage from this test)

fn foo() -> Datum {
    let x: Pair = Pair {
        first: Datum { value: 1_u32 },
        second: Datum { value: 2_u32 },
    };
    let a: Datum = x.first;
    let b: Datum = x.first;
    return b;
}

Source location: tests/borrowck.rs:628 (all coverage from this test)

fn foo() -> Datum {
    let x: Pair = Pair {
        first: Datum { value: 1_u32 },
        second: Datum { value: 2_u32 },
    };
    let a: Pair = x;
    let b: Datum = x.first;
    return b;
}

Source location: tests/borrowck.rs:672 (all coverage from this test)

fn foo() -> u32 {
    let x: Outer = Outer {
        foo: Inner { bar: 1_u32 },
    };
    let a: Inner = x.foo;
    let b: u32 = x.foo.bar;
    return b;
}

Source location: tests/borrowck.rs:721 (all coverage from this test)

fn foo() -> Datum {
    exists<'r0, 'r1> {
        let x: Datum = Datum { value: 0_u32 };
        let r: &'r0 Datum = &'r1 x;
        let y: Datum = *r;
        return y;
    }
}

Source location: tests/borrowck.rs:1476 (all coverage from this test)

fn foo() -> Datum {
    exists<'r0, 'r1> {
        let x: Datum = Datum { value: 0_u32 };
        let r: &'r0 mut Datum = &'r1 mut x;
        let y: Datum = *r;
        return y;
    }
}

Proof trees omitted for the remaining 26 tests; each one is on its test’s page in Coverage by test.

Source location: tests/borrowck.rs:2232 (all coverage from this test)

fn foo() -> Datum {
    exists<'r0, 'r1> {
        let x: Datum = Datum { value: 0_u32 };
        let r: &'r0 Datum = &'r1 x;
        let y: Datum = x;
        return *r;
    }
}

Source location: tests/borrowck.rs:2470 (all coverage from this test)

fn min_problem_case_3<'a>(m: &'a mut Map) -> &'a mut Map {
    exists<'r0, 'r1> {
        let n: &'r0 mut Map = &'r0 mut *m;
        if true {
            return n;
        } else {
            let o: &'r1 mut Map = &'r1 mut *m;
            return o;
        }
    }
}

Source location: tests/borrowck.rs:3288 (all coverage from this test)

fn foo<'a>(m: &'a mut Map) -> &'a mut Map {
    exists<'r0, 'r1> {
        let n: &'r0 mut Map = &'r0 mut *m;
        if false {
            return n;
        } else {
            let o: &'r1 mut Map = &'r1 mut *m;
            return o;
        }
    }
}

Source location: tests/borrowck.rs:3470 (all coverage from this test)

fn foo<'a, 'b>(a: &'a u32) -> &'b u32 {
    let r: &'b u32 = identity::<&'b u32>(a);
    return r;
}

Source location: tests/borrowck.rs:3536 (all coverage from this test)

fn bar() -> u32 {
    exists<'r0, 'r1, 'r2> {
        let v: u32 = 0_u32;
        let p: &'r0 u32 = &'r1 v;
        let _: u32 = foo::<'r2>(&'r2 mut v);
        return *p;
    }
}

Source location: tests/borrowck.rs:3618 (all coverage from this test)

fn foo() -> u32 {
    exists<'r0, 'r1> {
        let v1: u32 = 22_u32;
        let v2: &'r0 mut u32 = &'r1 mut v1;
        let w: Wrapper = Wrapper { value: v1 };
        return *v2;
    }
}

Source location: tests/borrowck.rs:3715 (all coverage from this test)

fn reborrow<'a>(a: &'a mut u8) -> &'a mut u8 {
    exists<'r0, 'r1, 'r2, 'r3> {
        // This creates an outlives constraint
        let b: &'r1 mut u8 = &'r0 mut *a;
        if true {
            return b;
        } else {
            // this means the loan remains live
        }

        // If the outlives constraint propagated here,
        // we would get an error.
        let c: &'r3 mut u8 = &'r2 mut *a;
        return c;
    }
}

Source location: tests/borrowck.rs:3891 (all coverage from this test)

fn foo(f: Pair) -> () {
    let s: Datum = f.x;
}

Source location: tests/borrowck.rs:4035 (all coverage from this test)

fn foo<'a, 'b>(p: &'a mut u32) -> u32 {
    let q: &'b mut u32 = &'b mut *p;
    q;
    return 0_u32;
}

Source location: tests/borrowck.rs:4326 (all coverage from this test)

fn conditional() -> u32 {
    exists<'r0, 'r1, 'r2, 'r3> {
        let b: X = X { value: 0_u32 };
        let p: &'r0 mut X = &'r1 mut b;
        'l: loop {
            let now: &'r2 mut X = &'r2 mut *p;
            if true {
                if true {
                    let next: &'r3 mut X = next_of::<'r3>(&'r3 mut *now);
                    p = next;
                } else {
                }
            } else {
                break 'l;
            }
        }
        return 0_u32;
    }
}

Source location: tests/borrowck.rs:4592 (all coverage from this test)

fn next<'a>(d: &'a mut Decoder) -> &'a u32 {
    exists<'r0, 'r1> {
        'l: loop {
            let buf: &'r0 u32 = fill_buf::<'r0>(&'r0 mut (*d).buf_read);
            let s: &'r1 u32 = decode::<'r1>(buf);
            if true {
                return s;
            } else {
            }
        }
    }
}

Source location: tests/borrowck.rs:4715 (all coverage from this test)

fn next<'s>(f: &'s mut Filter) -> &'s mut u32 {
    exists<'r0, 'r1, 'r2> {
        'l: loop {
            let item: &'r0 mut u32 = iter_next::<'r0>(&'r0 mut (*f).iter);
            if true {
                let keep: bool = call_predicate::<'r1, 'r2>(&'r1 mut (*f).predicate, &'r2 *item);
                if keep {
                    return item;
                } else {
                }
            } else {
                break 'l;
            }
        }
        return no_item::<'s>();
    }
}

Source location: tests/mir_typeck.rs:345 (all coverage from this test)

fn bar() -> u32 {
    let v1: u32 = foo(0_u32);
    return v1;
}

Source location: tests/mir_typeck.rs:392 (all coverage from this test)

fn bar(v1: ()) -> () {
    let v0: () = foo(v1);
    return v0;
}

Source location: tests/mir_typeck.rs:416 (all coverage from this test)

fn bar(v1: u32) -> u32 {
    let v0: u32 = identity(v1);
    return v0;
}

Source location: tests/mir_typeck.rs:488 (all coverage from this test)

fn bar(v1: u32) -> u32 {
    let v0: u32 = identity::<bool>(v1);
    return v0;
}

Source location: tests/mir_typeck.rs:532 (all coverage from this test)

fn bar(v1: u32) -> u32 {
    let v0: u32 = identity::<u32>(v1, v1);
    return v0;
}

Source location: tests/mir_typeck.rs:568 (all coverage from this test)

fn bar(v1: u32) -> u32 {
    let v0: u32 = identity::<u32, u32>(v1);
    return v0;
}

Source location: tests/mir_typeck.rs:848 (all coverage from this test)

fn foo (v1: u32) -> u32 {
    let v2: Dummy = Dummy { value: false };
    return v1;
}

Source location: tests/mir_typeck.rs:876 (all coverage from this test)

fn foo (v1: u32) -> u32 {
    let v2: u32 = Nonexistent { value: false };
    return v1;
}

Source location: tests/mir_typeck.rs:902 (all coverage from this test)

fn main() -> () {
    let s: S = S { x: 1_u32, x: 2_u32 };
}

Source location: tests/mir_typeck.rs:1218 (all coverage from this test)

fn foo() -> () {
    let x: i32 = 1_i32 + 2_u32;
}

Source location: tests/mir_typeck.rs:1270 (all coverage from this test)

fn foo() -> () {
    let x: i32 = 10_i32 - 3_u32;
}

Source location: tests/mir_typeck.rs:1323 (all coverage from this test)

fn foo() -> () {
    let x: i32 = 3_i32 * 4_u32;
}

Source location: tests/mir_typeck.rs:1349 (all coverage from this test)

fn foo() -> () {
    let x: bool = true * false;
}

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