Test generic_mismatch

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_via.rs:8:1: 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:8:1: 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:54:1: 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:54:1: 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 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 &^lt0_0 mut ^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()`"#]])
}

Rules proved (0)

This test records no positive coverage.

Premises failed (15)

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.

Proof trees