Positive coverage: can_outlive / existential target

29 tests exercised this rule:

Source location: tests/borrowck.rs:2025

#[test]
fn min_problem_case_3() {
    FormalityTest::new(feature_gate_program(NLL_GATE, MIN_PROBLEM_CASE_3))
        .skip_execute()
        .err(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"#]]);

    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        MIN_PROBLEM_CASE_3,
    ))
    .skip_execute()
    .ok();

    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        MIN_PROBLEM_CASE_3,
    ))
    .skip_execute()
    .ok();
}

Source location: tests/borrowck.rs:2032

#[test]
fn min_problem_case_3() {
    FormalityTest::new(feature_gate_program(NLL_GATE, MIN_PROBLEM_CASE_3))
        .skip_execute()
        .err(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"#]]);

    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        MIN_PROBLEM_CASE_3,
    ))
    .skip_execute()
    .ok();

    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        MIN_PROBLEM_CASE_3,
    ))
    .skip_execute()
    .ok();
}

Source location: tests/borrowck.rs:2220

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

Source location: tests/borrowck.rs:2341

fn min_problem_case_4<'a>(list: &'a mut Map, list2: &'a mut Map) -> u32 {
    exists<'r0> {
        let num: &'r0 mut u32 = &mut 'r0 (*list).value;
        list = &mut 'a *list2;
        num;
        return 0_u32;
    }
}