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Negative coverage: borrow_check_statement / if / premise borrow_check_block(env, assumptions, state, else_block, places_live_on_exit) => else_state

Premise at line 221. Observed failure causes: failed_judgment.

if
LineCoverageSource
210(borrow_check_expr_has_ty(
env,
assumptions,
state,
condition,
Ty::bool(),
Either(then_block, else_block).live_before(env, &state, places_live_on_exit),
) => state)
2202(borrow_check_block(env, assumptions, state, then_block, places_live_on_exit) => then_state)
2213(borrow_check_block(env, assumptions, state, else_block, places_live_on_exit) => else_state)
224N/A(let state: FlowState = Union((then_state, else_state)).upcast())
──────── ("if")
22645(borrow_check_statement(env, assumptions, state, Stmt::If { condition, then_block, else_block }, places_live_on_exit) => (env, state))

3 tests failed proving this premise:


Source location: tests/borrowck.rs:1989

#[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();
}
Failed proof tree

Source location: tests/borrowck.rs:2798

#[test]
fn if_false_borrowck() {
    FormalityTest::new(feature_gate_program(NLL_GATE, IF_FALSE_BORROWCK))
        .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, IF_FALSE_BORROWCK))
        .skip_execute()
        .ok();

    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        IF_FALSE_BORROWCK,
    ))
    .skip_execute()
    .ok();
}
Failed proof tree

Source location: tests/mir_typeck.rs:147

fn foo (b: bool) -> u32 {
    if b {
        return 1_u32;
    } else {
        return false;
    }
}
Failed proof tree