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Test T_and_Local_Bar_T

Source location: tests/coherence_overlap.rs:415

#[test]
fn T_and_Local_Bar_T() {
    FormalityTest::new(crates![crate core {
        trait Foo { }

        trait Bar<U> { }

        impl<T> Foo for T { }

        impl<T> Foo for T where LocalType: Bar<T> { }

        struct LocalType { }
    }])
    .err(expect_test::expect![[r#"
        the rule "different trait" at (coherence.rs) failed because
          condition evaluated to false: `impl_a.trait_id() != impl_b.trait_id()`

        crates/formality-rust/src/prove/prove_via.rs:8:1: no applicable rules for prove_via { goal: ! Bar(LocalType, !ty_1), via: !ty_0 = !ty_1, assumptions: {!ty_0 = !ty_1, Bar(LocalType, !ty_1)}, env: Env { variables: [!ty_0, !ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:8:1: no applicable rules for prove_via { goal: ! Bar(LocalType, !ty_1), via: Bar(LocalType, !ty_1), assumptions: {!ty_0 = !ty_1, Bar(LocalType, !ty_1)}, env: Env { variables: [!ty_0, !ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        the rule "negative impl" at (prove_wc.rs) failed because
          expression evaluated to an empty collection: `decls.neg_impl_decls(&trait_ref.trait_id)`

        the rule "not goal" at (coherence.rs) failed because
          failed to prove {!ty_1 = !ty_2, Bar(LocalType, !ty_2)} given {}, got [Constraints { env: Env { variables: [!ty_1, !ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: false, substitution: {} }]

        the rule "same impl" at (coherence.rs) failed because
          condition evaluated to false: `impl_a == impl_b`
            impl_a = impl <ty> Foo for ^ty0_0 { }
            impl_b = impl <ty> Foo for ^ty0_0 where LocalType : Bar <^ty0_0> { }"#]])
}

Rules proved (0)

This test records no positive coverage.

Premises failed (10)

The last column links to the premise’s page when the judgment view counts this failure against that premise. It does not when the premise is read as infallible, or when the failure was blamed inside a multi-line premise that carries no record on its own first line.

JudgmentRulePremiseAll tests of this premise
check_coherencecheck_coherencefor_all(impl_a in current_crate_impls) (for_all(… (line 16, blamed at line 18)not counted by the judgment view
overlap_check_implsame implif impl_a == impl_b (line 72)6 tests
overlap_check_impldifferent traitif impl_a.trait_id() != impl_b.trait_id() (line 79)6 tests
overlap_check_implnot goalprove_not_goal(program, env, (), (Wcs::all_eq(&a… (line 106)6 tests
overlap_check_implinvertedprove_goal(program, env, (Wcs::all_eq(&a.trait_r… (line 119)5 tests
check_all_cratescheck all prefixesfor_all(i in 0..crates.len()) (let program = cra… (line 51, blamed at line 53)not counted by the judgment view
check_cratecheck cratecheck_coherence(program, c) => () (line 74)12 tests
prove_wcassumptionprove_via(decls, env, assumptions, a, goal) => c (line 48)26 tests
prove_wcnegative impli in decls.neg_impl_decls(&trait_ref.trait_id) (line 93)5 tests
prove_wc_listsomeprove_wc(decls, env, assumptions, wc0) => c (line 26)47 tests

Proof trees

Failed proof tree