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Negative coverage: prove_after / prove_after / premise prove(decls, c1.env(), assumptions, goal) => c2

Premise at line 19. Observed failure causes: failed_judgment.

prove_after
LineCoverageSource
18N/A(let (assumptions, goal) = c1.substitution().apply((assumptions, goal)))
1917(prove(decls, c1.env(), assumptions, goal) => c2)
──────── ("prove_after")
21137(prove_after(decls, c1, assumptions, goal) => c1.seq(c2))

17 tests failed proving this premise:


Source location: crates/formality-rust/src/prove/prove/test/adt_wf.rs:44

#[test]
fn not_well_formed_adt() {
    let assumptions: Wcs = Wcs::t();
    let goal: Parameter = term("X<u64>");
    prove(
        decls(),
        Env::default(),
        assumptions,
        Relation::WellFormed(goal),
    )
    .assert_err(expect![[r#"
        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: u64 = u32, via: Foo(u64), assumptions: {Foo(u64)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u64, via: Foo(u64), assumptions: {Foo(u64)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u32, via: Foo(u64), assumptions: {Foo(u64)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

        the rule "trait implied bound" at (prove_wc.rs) failed because
          expression evaluated to an empty collection: `decls.trait_invariants()`"#]]);
}
Failed proof tree

Source location: crates/formality-rust/src/prove/prove/test/eq_assumptions.rs:41

#[test]
fn test_normalize_assoc_ty_existential0() {
    test_prove(
        Program::empty(),
        term("exists<A> {} => {for<T> if { <T as Iterator>::Item = u32 } <A as Iterator>::Item = u32}"),
    ).assert_err(
    expect![[r#"
        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: <?ty_0 as Iterator>::Item = u32, via: <!ty_1 as Iterator>::Item = u32, assumptions: {<!ty_1 as Iterator>::Item = u32}, env: Env { variables: [?ty_0, !ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        the rule "existential-nonvar" at (prove_eq.rs) failed because
          pattern `None` did not match value `Some(!ty_1)`

        the rule "existential-universal" at (prove_eq.rs) failed because
          condition evaluated to false: `env.universe(p) < env.universe(v)`

        the rule "existential-nonvar" at (prove_eq.rs) failed because
          pattern `None` did not match value `Some(!ty_1)`

        the rule "existential-universal" at (prove_eq.rs) failed because
          condition evaluated to false: `env.universe(p) < env.universe(v)`

        the rule "normalize-via-impl" at (prove_normalize.rs) failed because
          expression evaluated to an empty collection: `decls.alias_eq_decls(&a.name)`

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: <!ty_0 as Iterator>::Item = <?ty_1 as Iterator>::Item, via: <!ty_0 as Iterator>::Item = u32, assumptions: {<!ty_0 as Iterator>::Item = u32}, env: Env { variables: [?ty_1, !ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = ?ty_1, via: <!ty_0 as Iterator>::Item = u32, assumptions: {<!ty_0 as Iterator>::Item = u32}, env: Env { variables: [?ty_1, !ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        the rule "existential-nonvar" at (prove_eq.rs) failed because
          pattern `None` did not match value `Some(!ty_0)`

        the rule "existential-universal" at (prove_eq.rs) failed because
          condition evaluated to false: `env.universe(p) < env.universe(v)`

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: ?ty_1, via: <!ty_0 as Iterator>::Item = u32, assumptions: {<!ty_0 as Iterator>::Item = u32}, env: Env { variables: [?ty_1, !ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: u32 = <?ty_1 as Iterator>::Item, via: <!ty_0 as Iterator>::Item = u32, assumptions: {<!ty_0 as Iterator>::Item = u32}, env: Env { variables: [?ty_1, !ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        the rule "existential-nonvar" at (prove_eq.rs) failed because
          pattern `None` did not match value `Some(!ty_0)`

        the rule "existential-universal" at (prove_eq.rs) failed because
          condition evaluated to false: `env.universe(p) < env.universe(v)`

        the rule "existential-nonvar" at (prove_eq.rs) failed because
          pattern `None` did not match value `Some(!ty_0)`

        the rule "existential-universal" at (prove_eq.rs) failed because
          condition evaluated to false: `env.universe(p) < env.universe(v)`

        the rule "normalize-via-impl" at (prove_normalize.rs) failed because
          expression evaluated to an empty collection: `decls.alias_eq_decls(&a.name)`

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: ?ty_1 = !ty_0, via: <!ty_0 as Iterator>::Item = u32, assumptions: {<!ty_0 as Iterator>::Item = u32}, env: Env { variables: [?ty_1, !ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        the rule "existential-nonvar" at (prove_eq.rs) failed because
          pattern `None` did not match value `Some(!ty_0)`

        the rule "existential-universal" at (prove_eq.rs) failed because
          condition evaluated to false: `env.universe(p) < env.universe(v)`

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: ?ty_1, via: <!ty_0 as Iterator>::Item = u32, assumptions: {<!ty_0 as Iterator>::Item = u32}, env: Env { variables: [?ty_1, !ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        the rule "existential-nonvar" at (prove_eq.rs) failed because
          pattern `None` did not match value `Some(!ty_0)`

        the rule "existential-universal" at (prove_eq.rs) failed because
          condition evaluated to false: `env.universe(p) < env.universe(v)`

        the rule "existential-nonvar" at (prove_eq.rs) failed because
          pattern `None` did not match value `Some(!ty_0)`

        the rule "existential-universal" at (prove_eq.rs) failed because
          condition evaluated to false: `env.universe(p) < env.universe(v)`

        the rule "normalize-via-impl" at (prove_normalize.rs) failed because
          expression evaluated to an empty collection: `decls.alias_eq_decls(&a.name)`"#]]);
}
Failed proof tree

Source location: crates/formality-rust/src/prove/prove/test/eq_partial_eq.rs:44

#[test]
fn universals_not_eq() {
    let goal: Wc = term("for<T, U> if {Eq(T)} PartialEq(U)");
    prove(decls(), (), (), goal)
    .assert_err(
    expect![[r#"
        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: PartialEq(!ty_2), via: Eq(!ty_1), assumptions: {Eq(!ty_1)}, env: Env { variables: [!ty_1, !ty_2], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = !ty_1, via: Eq(!ty_0), assumptions: {Eq(!ty_0)}, env: Env { variables: [!ty_0, !ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: !ty_0, via: Eq(!ty_0), assumptions: {Eq(!ty_0)}, env: Env { variables: [!ty_0, !ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: !ty_1, via: Eq(!ty_0), assumptions: {Eq(!ty_0)}, env: Env { variables: [!ty_0, !ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: Eq(!ty_1), via: PartialEq(?ty_2), assumptions: {Eq(!ty_0)}, env: Env { variables: [!ty_0, !ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false } }"#]]);
}
Failed proof tree

Source location: crates/formality-rust/src/prove/prove/test/magic_copy.rs:25

#[test]
fn all_t_not_magic() {
    test_prove(decls(), term("{} => {for<T> Magic(T)}")).assert_err(
    expect![[r#"
        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = u32, via: Copy(!ty_0), assumptions: {Copy(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: !ty_0, via: Copy(!ty_0), assumptions: {Copy(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u32, via: Copy(!ty_0), assumptions: {Copy(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: Magic(!ty_0), via: Copy(?ty_1), assumptions: {}, env: Env { variables: [!ty_0, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: Magic(!ty_1), via: Copy(?ty_2), assumptions: {}, env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false } }"#]]);
}
Failed proof tree

Source location: crates/formality-rust/src/prove/prove/test/magic_copy.rs:40

#[test]
fn all_t_not_copy() {
    test_prove(decls(), term("{} => {for<T> Copy(T)}")).assert_err(
    expect![[r#"
        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = u32, via: Copy(!ty_0), assumptions: {Copy(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: !ty_0, via: Copy(!ty_0), assumptions: {Copy(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u32, via: Copy(!ty_0), assumptions: {Copy(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = u32, via: Copy(!ty_0), assumptions: {Copy(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: !ty_0, via: Copy(!ty_0), assumptions: {Copy(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u32, via: Copy(!ty_0), assumptions: {Copy(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: Magic(!ty_0), via: Copy(?ty_1), assumptions: {}, env: Env { variables: [!ty_0, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }"#]]);
}
Failed proof tree

Source location: crates/formality-rust/src/prove/prove/test/occurs_check.rs:48

#[test]
fn indirect_cycle_1() {
    test_prove(decls(), term("exists<A, B> {} => {A = Vec<B>, B = A}")).assert_err(expect![[r#"
        failed at (proven_set.rs) because
          `?ty_0` occurs in `Vec<?ty_0>`

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:19:1: no applicable rules for prove_normalize { p: ?ty_0, assumptions: {}, env: Env { variables: [?ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:19:1: no applicable rules for prove_normalize { p: Vec<?ty_0>, assumptions: {}, env: Env { variables: [?ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }"#]]);
}
Failed proof tree

Source location: crates/formality-rust/src/prove/prove/test/occurs_check.rs:60

#[test]
fn indirect_cycle_2() {
    test_prove(decls(), term("exists<A, B> {} => {B = A, A = Vec<B>}")).assert_err(expect![[r#"
        failed at (proven_set.rs) because
          `?ty_0` occurs in `Vec<?ty_0>`

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:19:1: no applicable rules for prove_normalize { p: ?ty_0, assumptions: {}, env: Env { variables: [?ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:19:1: no applicable rules for prove_normalize { p: Vec<?ty_0>, assumptions: {}, env: Env { variables: [?ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }"#]]);
}
Failed proof tree

Source location: tests/basic_tests.rs:34

#[test]
fn hello_world_fail() {
    FormalityTest::new(crates![crate Foo {
                trait Foo<T> where T: Bar<Self> {}

                trait Bar<T> where T: Baz {}

                trait Baz {}
            }]).err(expect_test::expect![[r#"
                crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: @ WellFormedTraitRef(Bar(!ty_0, !ty_1)), via: Bar(!ty_0, !ty_1), assumptions: {Bar(!ty_0, !ty_1)}, env: Env { variables: [!ty_1, !ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

                crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: Baz(!ty_1), via: Bar(!ty_0, !ty_1), assumptions: {Bar(!ty_0, !ty_1)}, env: Env { variables: [!ty_1, !ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

                the rule "trait implied bound" at (prove_wc.rs) failed because
                  expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}
Failed proof tree

Source location: tests/basic_tests.rs:85

#[test]
fn basic_where_clauses_fail() {
    FormalityTest::new(crates![crate core {
                #![feature(non_lifetime_binders)]
                trait A<T> where T: B { }

                trait B { }

                trait WellFormed where for<T> u32: A<T> { }
            }]).err(expect_test::expect![[r#"
            crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: @ WellFormedTraitRef(A(u32, !ty_1)), via: A(u32, ?ty_2), assumptions: {for <ty> A(u32, ^ty0_0)}, env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false } }

            crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: B(!ty_0), via: A(u32, ?ty_1), assumptions: {for <ty> A(u32, ^ty0_0)}, env: Env { variables: [!ty_0, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

            the rule "trait implied bound" at (prove_wc.rs) failed because
              expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}
Failed proof tree

Source location: tests/borrowck.rs:453

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;
    }
}
Failed proof tree
… (200 of 1023 nodes shown)

Source location: tests/borrowck.rs:1112

fn foo() -> Datum {
    exists<'r0, 'r1> {
        let x: Datum = Datum { value: 0 _ u32 };
        let r: &mut 'r0 Datum = &mut 'r1 x;
        let y: Datum = *r;
        return y;
    }
}

Proof trees omitted for the remaining 7 tests.


Source location: tests/consts.rs:32

#[test]
fn mismatch() {
    FormalityTest::new(crates![crate Foo {
                trait Foo<const C> where type_of_const C is bool {}

                impl Foo<u32(42)> for u32 {}
            }]).err(expect_test::expect![[r#"
                crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:19:1: no applicable rules for prove_normalize { p: u32, assumptions: {}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

                crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:19:1: no applicable rules for prove_normalize { p: bool, assumptions: {}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

                the rule "trait implied bound" at (prove_wc.rs) failed because
                  expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}

Source location: tests/consts.rs:68

#[test]
fn generic_mismatch() {
    FormalityTest::new(crates![crate Foo {
                trait Foo<const C> where type_of_const C is bool {}

                // Here, the impl is assuming C is u32, which mismatches the trait bound.
                impl<const C> Foo<C> for u32 where type_of_const C is u32 {}
            }]).err(expect_test::expect![[r#"
                crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: Foo(u32, !const_0), via: @ ConstHasType(!const_0 , u32), assumptions: {@ ConstHasType(!const_0 , u32)}, env: Env { variables: [!const_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

                crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: u32 = bool, via: @ ConstHasType(!const_0 , u32), assumptions: {@ ConstHasType(!const_0 , u32)}, env: Env { variables: [!const_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

                crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u32, via: @ ConstHasType(!const_0 , u32), assumptions: {@ ConstHasType(!const_0 , u32)}, env: Env { variables: [!const_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

                crates/formality-rust/src/prove/prove/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: bool, via: @ ConstHasType(!const_0 , u32), assumptions: {@ ConstHasType(!const_0 , u32)}, env: Env { variables: [!const_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

                crates/formality-rust/src/prove/prove/prove/prove_const_has_type.rs:11:1: no applicable rules for prove_const_has_type { constant: !const_0, assumptions: {@ ConstHasType(!const_0 , u32)}, env: Env { variables: [!const_0], bias: Soundness, pending: [], allow_pending_outlives: false }, decls: program([crate core { trait Copy <ty> { } impl Copy for () { } impl Copy for u8 { } impl Copy for u16 { } impl Copy for u32 { } impl Copy for u64 { } impl Copy for i8 { } impl Copy for i16 { } impl Copy for i32 { } impl Copy for i64 { } impl Copy for bool { } impl Copy for usize { } impl Copy for isize { } impl <lt, ty> Copy for &^lt0_0 ^ty0_1 { } trait Drop <ty> { } trait Derefable <ty> { type Target : [] ; } impl <lt, ty> Derefable for &^lt0_0 ^ty0_1 where ^ty0_1 : ^lt0_0 { type Target = ^ty1_1 ; } impl <lt, ty> Derefable for &mut ^lt0_0 ^ty0_1 where ^ty0_1 : ^lt0_0 { type Target = ^ty1_1 ; } }, crate Foo { trait Foo <ty, const> where type_of_const ^const0_1 is bool { } impl <const> Foo <^const0_0> for u32 where type_of_const ^const0_0 is u32 { } }], 222) }

                the rule "trait implied bound" at (prove_wc.rs) failed because
                  expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}

Source location: tests/drop.rs:99

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

            struct MyStruct<T> {
                value: T,
            }

            impl<T> Drop for MyStruct<T> where T: Clone {}
        }
    ])
    .err(expect_test::expect![[r#"
        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: Clone(!ty_0), via: Drop(MyStruct<!ty_0>), assumptions: {Drop(MyStruct<!ty_0>)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        the rule "trait implied bound" at (prove_wc.rs) failed because
          expression evaluated to an empty collection: `decls.trait_invariants()`

        the rule "trait implied bound" at (prove_wc.rs) failed because
          expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}

Source location: tests/mir_typeck.rs:266

fn foo() -> () {
    let s2: S2<S1>;
}

Source location: tests/references.rs:13


Source location: tests/well_formed_trait_ref.rs:37

#[test]
fn missing_dependent_where_clause() {
    FormalityTest::new(crates![crate foo {
        trait Trait1 {}

        trait Trait2 {}

        struct S1<T> where T: Trait1 {
            dummy: T,
        }

        struct S2<T> where S1<T> : Trait2 {
            dummy: T,
        }
    }])
    .err(expect_test::expect![[r#"
        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: @ WellFormedTraitRef(Trait2(S1<!ty_0>)), via: Trait2(S1<!ty_0>), assumptions: {Trait2(S1<!ty_0>)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: Trait1(!ty_0), via: Trait2(S1<!ty_0>), assumptions: {Trait2(S1<!ty_0>)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        the rule "trait implied bound" at (prove_wc.rs) failed because
          expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}