Negative coverage: prove_predicate / trait implied bound / premise ti in decls.trait_invariants()

Premise at line 106. Observed failure causes: empty_collection.

19 tests failed proving this premise:

Source location: crates/formality-rust/src/prove/test/adt_wf.rs:44 (all coverage from this test)

#[test]
fn not_well_formed_adt() {
    let assumptions: Predicates = Predicates::t();
    let goal: Parameter = term("X<u64>");
    prove(
        decls(),
        Env::default(),
        assumptions,
        AtomicPredicate::WellFormed(goal),
    )
    .assert_err(expect![[r#"
        crates/formality-rust/src/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_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_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_predicate.rs) failed because
          expression evaluated to an empty collection: `decls.trait_invariants()`"#]]);
}

Source location: tests/basic_tests.rs:34 (all coverage from this test)

#[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_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_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_predicate.rs) failed because
                  expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}

Source location: tests/basic_tests.rs:85 (all coverage from this test)

#[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_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_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_predicate.rs) failed because
                  expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}

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;
    }
}

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

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

Source location: tests/consts.rs:36 (all coverage from this test)

#[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_normalize.rs:22:1: 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_normalize.rs:22:1: 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_predicate.rs) failed because
                  expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}

Source location: tests/consts.rs:76 (all coverage from this test)

#[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_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_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_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_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_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 u128 { } impl Copy for i8 { } impl Copy for i16 { } impl Copy for i32 { } impl Copy for i64 { } impl Copy for i128 { } impl Copy for bool { } impl Copy for usize { } impl Copy for isize { } impl <lt, ty> Copy for &^lt0_0 ^ty0_1 { } trait Drop <ty> { fn drop <lt> (self : &^lt0_0 mut ^ty1_0) where ^ty1_0 : ^lt0_0 ; } 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 &^lt0_0 mut ^ty0_1 where ^ty0_1 : ^lt0_0 { type Target = ^ty1_1 ; } trait Sized <ty> { } impl Sized for () { } impl Sized for u8 { } impl Sized for u16 { } impl Sized for u32 { } impl Sized for u64 { } impl Sized for u128 { } impl Sized for i8 { } impl Sized for i16 { } impl Sized for i32 { } impl Sized for i64 { } impl Sized for i128 { } impl Sized for bool { } impl Sized for usize { } impl Sized for isize { } impl <lt, ty> Sized for &^lt0_0 ^ty0_1 { } impl <lt, ty> Sized for &^lt0_0 mut ^ty0_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_predicate.rs) failed because
                  expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}

Source location: tests/drop.rs:83 (all coverage from this test)

Source location: tests/drop.rs:250 (all coverage from this test)

Source location: tests/drop.rs:274 (all coverage from this test)

Proof trees omitted for the remaining 9 tests; each one is on its test’s page in Coverage by test.

Source location: tests/drop.rs:313 (all coverage from this test)

Source location: tests/mir_typeck.rs:321 (all coverage from this test)

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

Source location: tests/mir_typeck.rs:1394 (all coverage from this test)

fn main() -> () { require_marker::<S>; }
}])
tc_err(expect_test::expect![[r#"
error[E0277]: the trait bound `S: Marker` is not satisfied
  --> lib.rs
   |
13 |     require_marker::<S>;
   |                      ^ unsatisfied trait bound
   |
help: the trait `Marker` is not implemented for `S`
  --> lib.rs
   |
 3 | pub struct S {}
   | ^^^^^^^^^^^^
help: this trait has no implementations, consider adding one
  --> lib.rs
   |
 1 | pub trait Marker {}
   | ^^^^^^^^^^^^^^^^
note: required by a bound in `require_marker`
  --> lib.rs
   |
 5 | pub fn require_marker<T00>() -> ()
   |        -------------- required by a bound in this function
 6 | where
 7 |     T00: Marker,
   |          ^^^^^^ required by this bound in `require_marker`

For more information about this error, try `rustc --explain E0277`.
error: could not compile `test` (lib) due to 1 previous error
)
(expect_test::expect![[r#"
the rule "trait implied bound" at (prove_predicate.rs) failed because
  expression evaluated to an empty collection: `decls.trait_invariants()`"#]]);
}

ing the same function is still rejected. The where-clauses are now
ked both for the function name and by the call.
#[test]
generic_fn_call_with_unsatisfied_where_clause() {
alityTest::new(crates![crate test {
trait Marker {}
struct S {}
fn require_marker<T>() -> () where T: Marker { trusted }
fn main() -> () { require_marker::<S>(); }
}])
tc_err(expect_test::expect![[r#"
error[E0277]: the trait bound `S: Marker` is not satisfied
  --> lib.rs
   |
13 |     require_marker::<S>();
   |                      ^ unsatisfied trait bound
   |
help: the trait `Marker` is not implemented for `S`
  --> lib.rs
   |
 3 | pub struct S {}
   | ^^^^^^^^^^^^
help: this trait has no implementations, consider adding one
  --> lib.rs
   |
 1 | pub trait Marker {}
   | ^^^^^^^^^^^^^^^^
note: required by a bound in `require_marker`
  --> lib.rs
   |
 5 | pub fn require_marker<T00>() -> ()
   |        -------------- required by a bound in this function
 6 | where
 7 |     T00: Marker,
   |          ^^^^^^ required by this bound in `require_marker`

For more information about this error, try `rustc --explain E0277`.
error: could not compile `test` (lib) due to 1 previous error
)
(expect_test::expect![[r#"
the rule "trait implied bound" at (prove_predicate.rs) failed because
  expression evaluated to an empty collection: `decls.trait_invariants()`"#]]);
}

ng the function with a type that implements `Marker` is accepted.
#[test]
generic_fn_value_with_satisfied_where_clause() {
alityTest::new(crates![crate test {
trait Marker {}
impl Marker for u32 {}
fn require_marker<T>() -> () where T: Marker {}
fn main() -> () { require_marker::<u32>; }
}])
tc_ok()
);
}

#[test]
fn_value_with_forwarded_trait_bound() {
alityTest::new(crates![crate Foo {
trait Marker {}
impl Marker for u32 {}
fn require<T>() -> () where T: Marker {}
fn outer<T>() -> () where T: Marker { require::<T>; }
fn main() -> () { outer::<u32>(); }
}])
tc_ok()
);
}

#[test]
bare_fn_value_with_satisfied_where_clause() {
alityTest::new(crates![crate Foo {
trait Marker {}
impl Marker for u32 {}
fn require() -> () where u32: Marker {}
fn main() -> () { require; }
}])
tc_ok()
);
}

#[test]
fn_value_with_forwarded_lifetime_bound() {
alityTest::new(crates![crate Foo {
fn require<'a, 'b>() -> () where 'a: 'b {}
fn outer<'a, 'b>() -> () where 'a: 'b { require::<'a, 'b>; }
fn main() -> () { outer::<'static, 'static>(); }
}])
tc_ok()
);
}

#[test]
fn_value_with_unsatisfied_lifetime_bound() {
alityTest::new(crates![crate Foo {
fn require<'a, 'b>() -> () where 'a: 'b {}
fn outer<'a, 'b>() -> () { require::<'a, 'b>; }
fn main() -> () {}
}])
tc_err(expect_test::expect![[r#"
error: lifetime may not live long enough
 --> lib.rs
  |
7 | pub fn outer<'a00, 'a01>() -> () {
  |              ----  ---- lifetime `'a01` defined here
  |              |
  |              lifetime `'a00` defined here
8 |     require::<'a00, 'a01>;
  |     ^^^^^^^^^^^^^^^^^^^^^ requires that `'a00` must outlive `'a01`
  |
  = help: consider adding the following bound: `'a00: 'a01`

error: could not compile `Foo` (lib) due to 1 previous error
)
(expect_test::expect!["crates/formality-rust/src/prove/prove_outlives.rs:8:1: no applicable rules for prove_outlives { a: !lt_0, b: !lt_1, assumptions: {}, env: Env { variables: [!lt_0, !lt_1], bias: Soundness, pending: [], allow_pending_outlives: false } }"]);
}

ound assignment of an integer of a different type should fail.
#[test]
compound_add_mismatched_int_types() {
alityTest::new(crates![crate Foo {
fn foo() -> () {
    let x: u32 = 1_u32;
    x += 2_u8;
}

Source location: tests/mir_typeck.rs:1438 (all coverage from this test)

fn main() -> () { require_marker::<S>(); }
}])
tc_err(expect_test::expect![[r#"
error[E0277]: the trait bound `S: Marker` is not satisfied
  --> lib.rs
   |
13 |     require_marker::<S>();
   |                      ^ unsatisfied trait bound
   |
help: the trait `Marker` is not implemented for `S`
  --> lib.rs
   |
 3 | pub struct S {}
   | ^^^^^^^^^^^^
help: this trait has no implementations, consider adding one
  --> lib.rs
   |
 1 | pub trait Marker {}
   | ^^^^^^^^^^^^^^^^
note: required by a bound in `require_marker`
  --> lib.rs
   |
 5 | pub fn require_marker<T00>() -> ()
   |        -------------- required by a bound in this function
 6 | where
 7 |     T00: Marker,
   |          ^^^^^^ required by this bound in `require_marker`

For more information about this error, try `rustc --explain E0277`.
error: could not compile `test` (lib) due to 1 previous error
)
(expect_test::expect![[r#"
the rule "trait implied bound" at (prove_predicate.rs) failed because
  expression evaluated to an empty collection: `decls.trait_invariants()`"#]]);
}

ng the function with a type that implements `Marker` is accepted.
#[test]
generic_fn_value_with_satisfied_where_clause() {
alityTest::new(crates![crate test {
trait Marker {}
impl Marker for u32 {}
fn require_marker<T>() -> () where T: Marker {}
fn main() -> () { require_marker::<u32>; }
}])
tc_ok()
);
}

#[test]
fn_value_with_forwarded_trait_bound() {
alityTest::new(crates![crate Foo {
trait Marker {}
impl Marker for u32 {}
fn require<T>() -> () where T: Marker {}
fn outer<T>() -> () where T: Marker { require::<T>; }
fn main() -> () { outer::<u32>(); }
}])
tc_ok()
);
}

#[test]
bare_fn_value_with_satisfied_where_clause() {
alityTest::new(crates![crate Foo {
trait Marker {}
impl Marker for u32 {}
fn require() -> () where u32: Marker {}
fn main() -> () { require; }
}])
tc_ok()
);
}

#[test]
fn_value_with_forwarded_lifetime_bound() {
alityTest::new(crates![crate Foo {
fn require<'a, 'b>() -> () where 'a: 'b {}
fn outer<'a, 'b>() -> () where 'a: 'b { require::<'a, 'b>; }
fn main() -> () { outer::<'static, 'static>(); }
}])
tc_ok()
);
}

#[test]
fn_value_with_unsatisfied_lifetime_bound() {
alityTest::new(crates![crate Foo {
fn require<'a, 'b>() -> () where 'a: 'b {}
fn outer<'a, 'b>() -> () { require::<'a, 'b>; }
fn main() -> () {}
}])
tc_err(expect_test::expect![[r#"
error: lifetime may not live long enough
 --> lib.rs
  |
7 | pub fn outer<'a00, 'a01>() -> () {
  |              ----  ---- lifetime `'a01` defined here
  |              |
  |              lifetime `'a00` defined here
8 |     require::<'a00, 'a01>;
  |     ^^^^^^^^^^^^^^^^^^^^^ requires that `'a00` must outlive `'a01`
  |
  = help: consider adding the following bound: `'a00: 'a01`

error: could not compile `Foo` (lib) due to 1 previous error
)
(expect_test::expect!["crates/formality-rust/src/prove/prove_outlives.rs:8:1: no applicable rules for prove_outlives { a: !lt_0, b: !lt_1, assumptions: {}, env: Env { variables: [!lt_0, !lt_1], bias: Soundness, pending: [], allow_pending_outlives: false } }"]);
}

ound assignment of an integer of a different type should fail.
#[test]
compound_add_mismatched_int_types() {
alityTest::new(crates![crate Foo {
fn foo() -> () {
    let x: u32 = 1_u32;
    x += 2_u8;
}

Source location: tests/references.rs:13 (all coverage from this test)

Source location: tests/sized_trait.rs:27 (all coverage from this test)

#[test]
fn sized_bound_not_met_by_unimplemented_type() {
    FormalityTest::new(crates![crate Foo {
        struct S {}
        trait Needs<T> where T: Sized {}
        impl Needs<S> for u32 {}
    }])
    .rustc_ok()
    .err(expect_test::expect![[r#"
        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = &?lt_0 ?ty_1, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [?lt_0, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: S, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [?lt_0, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: &?lt_0 ?ty_1, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [?lt_0, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = &?lt_0 mut ?ty_1, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [?lt_0, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: S, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [?lt_0, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: &?lt_0 mut ?ty_1, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [?lt_0, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

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

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

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

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

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

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = i128, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: i128, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = i16, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: i16, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = i32, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: i32, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = i64, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: i64, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = i8, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: i8, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

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

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

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = u128, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u128, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = u16, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u16, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

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

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

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = u64, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

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

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: S = u8, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u8, via: Sized(S), assumptions: {Sized(S)}, env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

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

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

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

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

Source location: tests/sized_trait.rs:187 (all coverage from this test)

#[test]
fn generic_parameter_requires_explicit_sized_bound() {
    // Generated Rust still gives T an implicit Sized bound until #500 lands.
    // Formality must already require an explicit bound on this impl.
    FormalityTest::new(crates![crate Foo {
        trait Needs<T> where T: Sized {}
        impl<T> Needs<T> for u32 {}
    }])
    .rustc_ok()
    .err(expect_test::expect![[r#"
        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = &?lt_1 ?ty_2, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0, ?lt_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: !ty_0, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0, ?lt_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: &?lt_1 ?ty_2, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0, ?lt_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = &?lt_1 mut ?ty_2, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0, ?lt_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: !ty_0, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0, ?lt_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: &?lt_1 mut ?ty_2, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0, ?lt_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

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

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

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

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

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

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = i128, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: i128, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = i16, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: i16, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = i32, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: i32, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = i64, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: i64, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = i8, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: i8, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

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

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

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = u128, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u128, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = u16, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u16, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

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

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

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = u64, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u64, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_via.rs:9:1: no applicable rules for prove_via { goal: !ty_0 = u8, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

        crates/formality-rust/src/prove/prove_normalize.rs:55:1: no applicable rules for prove_normalize_via { goal: u8, via: Sized(!ty_0), assumptions: {Sized(!ty_0)}, env: Env { variables: [!ty_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

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

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

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

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

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

Source location: tests/well_formed_trait_ref.rs:37 (all coverage from this test)

#[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_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_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_predicate.rs) failed because
          expression evaluated to an empty collection: `decls.trait_invariants()`"#]])
}

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