Positive coverage: prove_existential_var_eq / existential-nonvar

31 tests exercised this rule:

Source location: crates/formality-rust/src/prove/prove/test/eq_assumptions.rs:24

#[test]
fn test_b() {
    test_prove(
        Program::empty(),
        term("exists<A> {} => {for<T, U> if {T = u32, U = Vec<T>} A = U}"),
    )
    .assert_ok(expect!["{Constraints { env: Env { variables: [?ty_2, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => Vec<u32>, ?ty_2 => u32} }}"]);
}

Source location: crates/formality-rust/src/prove/prove/test/exists_constraints.rs:24

#[test]
fn exists_u_for_t() {
    test_prove(decls(), term("exists<U> {} => {Foo(U)}")).assert_ok(expect!["{Constraints { env: Env { variables: [?ty_2, ?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => Vec<?ty_2>} }}"]);
}

Source location: crates/formality-rust/src/prove/prove/test/occurs_check.rs:36

#[test]
fn eq_variable_to_rigid() {
    test_prove(decls(), term("exists<X, Y> {} => {X = Vec<Y>}")).assert_ok(expect!["{Constraints { env: Env { variables: [?ty_3, ?ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => Vec<?ty_3>, ?ty_2 => ?ty_3} }}"]);
}

Source location: crates/formality-rust/src/prove/prove/test/occurs_check.rs:42

#[test]
fn eq_rigid_to_variable() {
    test_prove(decls(), term("exists<X, Y> {} => {Vec<Y> = X}")).assert_ok(expect!["{Constraints { env: Env { variables: [?ty_3, ?ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => Vec<?ty_3>, ?ty_2 => ?ty_3} }}"]);
}

Source location: crates/formality-rust/src/prove/prove/test/simple_impl.rs:24

#[test]
fn vec_u32_debug() {
    let goal: Wc = term("Debug(Vec<u32>)");
    prove(decls(), (), (), goal).assert_ok(expect!["{Constraints { env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]);
}

Source location: crates/formality-rust/src/prove/prove/test/simple_impl.rs:30

#[test]
fn vec_vec_u32_debug() {
    let goal: Wc = term("Debug(Vec<Vec<u32>>)");
    prove(decls(), (), (), goal).assert_ok(expect!["{Constraints { env: Env { variables: [], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]);
}

Source location: tests/associated_type_normalization.rs:19

#[test]
fn test_mirror_normalizes_u32_to_u32() {
    test_where_clause(MIRROR, "exists<T> {} => {<u32 as Mirror>::Assoc = T}")
        .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => u32} }, Constraints { env: Env { variables: [?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => <u32 as Mirror>::Assoc} }}"]);
}

Source location: tests/borrowck.rs:1968

fn min_problem_case_3<'a>(m: &mut 'a Map) -> &mut 'a Map {
    exists<'r0, 'r1> {
        let n: &mut 'r0 Map = &mut 'r0 *m;
        if true {
            return n;
        } else {
            let o: &mut 'r1 Map = &mut 'r1 *m;
            return o;
        }
    }
}

Source location: tests/borrowck.rs:2041

fn foo() -> i32 {
    exists<'r0, 'r1> {
        let result: i32;
        {
            let v1: i32 = 22 _ i32;
            let v2: &'r0 i32 = &'r1 v1;
            result = *v2;
        }
        return result;
    }
}

Source location: tests/borrowck.rs:2156

fn min_problem_case_3<'a>(m: &mut 'a Map) -> &mut 'a Map {
    exists<'r0, 'r1> {
        let n: &mut 'r0 Map = &mut 'r0 *m;
        if true {
        } else {
        }
        let o: &mut 'r1 Map = &mut 'r1 *m;
        return o;
    }
}

Source location: tests/borrowck.rs:2277

fn min_problem_case_4<'a>(list: &mut 'a Map, list2: &mut 'a Map) -> u32 {
    exists<'r0> {
        let num: &mut 'r0 u32 = &mut 'r0 (*list).value;
        list = &mut 'a *list2;
        num;
        return 0 _ u32;
    }
}

Proof trees omitted for the remaining 21 tests.

Source location: tests/borrowck.rs:2410

fn foo () -> u32 {
    exists<'l_p, 'l_q, 'loan_0, 'loan_1, 'loan_2, 'loan_3> {
        let a: u32 = 0 _ u32;
        let b: u32 = 0 _ u32;
        // In Rustc, the 1-tuple is needed for some reason
        // Niko does not 100% understand, else rustc is able to
        // see that this program is safe.
        let q: &mut 'l_q u32 = &mut 'loan_0 a;
        let p: &mut 'l_p u32 = &mut 'loan_1 a;
        if true {
            p = &mut 'loan_1 a;
            q = &mut 'loan_2 b;
        } else {
            p = &mut 'loan_3 b;
        }
        *q = 1 _ u32;
        return *p;
    }
}

Source location: tests/borrowck.rs:2600

fn foo() -> u32 {
    exists<'r0, 'r1> {
        'a: loop {
            let x: i32 = 0 _ i32;
            let r: &'r0 i32 = &'r1 x;
            let _y: i32 = *r;
            continue 'a;
        }
    }
}

Source location: tests/borrowck.rs:2733

fn foo<'a>(m: &mut 'a Map) -> &mut 'a Map {
    exists<'r0, 'r1> {
        let n: &mut 'r0 Map = &mut 'r0 *m;
        if false {
            return n;
        } else {
            let o: &mut 'r1 Map = &mut 'r1 *m;
            return o;
        }
    }
}

Source location: tests/borrowck.rs:2828

fn bar() -> u32 {
    exists<'r1> {
        let v: u32 = 7 _ u32;
        let r: u32 = foo::<'r1>(&'r1 v);
        return r;
    }
}

Source location: tests/borrowck.rs:2922

fn bar() -> u32 {
    exists<'r0, 'r1> {
        let v: u32 = 1 _ u32;
        let p: &'r0 u32 = &'r1 v;
        foo(0 _ u32);
        return *p;
    }
}

Source location: tests/borrowck.rs:2976

fn foo() -> u32 {
    exists<'r0, 'r1, 'r2, 'r3> {
        let p: Point = Point { x: 0 _ u32, y: 0 _ u32 };
        let b1: &mut 'r0 u32 = &mut 'r1 p.x;
        let b2: &mut 'r2 u32 = &mut 'r3 p.y;
        *b1 = 1 _ u32;
        *b2 = 2 _ u32;
        return 0 _ u32;
    }
}

Source location: tests/borrowck.rs:3095

fn reborrow<'a>(a: &mut 'a u8) -> &mut 'a u8 {
    exists<'r0, 'r1, 'r2, 'r3> {
        if true {
            let b: &mut 'r1 u8 = &mut 'r0 *a;
            return b;
        } else { }

        let c: &mut 'r3 u8 = &mut 'r2 *a;
        return c;
    }
}

Source location: tests/borrowck.rs:3120

fn reborrow<'a>(a: &mut 'a u8) -> &mut 'a u8 {
    exists<'r0, 'r1, 'r2, 'r3> {
        // This creates an outlives constraint
        let b: &mut 'r1 u8 = &mut 'r0 *a;
        if true {
            return b;
        } else {
            // this means the loan remains live
        }

        // If the outlives constraint propagated here,
        // we would get an error.
        let c: &mut 'r3 u8 = &mut 'r2 *a;
        return c;
    }
}

Source location: tests/borrowck.rs:3137

fn reborrow<'a>(a: &mut 'a u8) -> &mut 'a u8 {
    exists<'r0, 'r1, 'r2, 'r3> {
        let b: &mut 'r1 u8 = &mut 'r0 *a;
        return b;
        let c: &mut 'r3 u8 = &mut 'r2 *a;
        return c;
    }
}

Source location: tests/borrowck.rs:3157

fn reborrow<'a>(a: &mut 'a u8) -> &mut 'a u8 {
    exists<'r0, 'r1, 'r2, 'r3> {
        if true {
            let b: &mut 'r1 u8 = &mut 'r0 *a;
            return b;
        } else {
            let c: &mut 'r3 u8 = &mut 'r2 *a;
            return c;
        }
    }
}

Source location: tests/coherence_orphan.rs:84

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

        trait Mirror {
            type Assoc : [];
        }

        impl<T> Mirror for T {
            type Assoc = T;
        }
    },
    crate foo {
        struct FooStruct {}
        impl CoreTrait for <FooStruct as Mirror>::Assoc {}
    }])
    .skip_execute()
    .ok()
}

Source location: tests/coherence_orphan.rs:196

#[test]
fn CoreTraitLocal_for_AliasToKnown_in_Foo() {
    // TODO: see comment in `orphan_check` from prev commit
    FormalityTest::new(crates![crate core {
        trait CoreTrait<T> {}

        trait Unit {
            type Assoc : [];
        }

        impl<T> Unit for T {
            type Assoc = ();
        }
    },
    crate foo {
        struct FooStruct {}
        impl CoreTrait<FooStruct> for <() as Unit>::Assoc {}
    }])
    .skip_execute()
    .ok()
}

Source location: tests/mir_typeck.rs:710

fn foo () -> u32 {
    exists<'a> {
        let v0: u32 = 0 _ u32;
        let v1: &'a u32 = &'a v0;
        let v2: u32 = *v1;
        return v2;
    }
}

Source location: tests/mir_typeck.rs:857

fn foo<'a>(v1: &'a Pair) -> u32 {
    exists<'r0> {
        let v2: u32 = (*v1).value;
        return v2;
    }
}

Source location: tests/projection.rs:25

#[test]
fn normalize_basic() {
    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> exists<U> {} => { <Vec<T> as Iterator>::Item = U }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => <Vec<!ty_1> as Iterator>::Item} }, Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => !ty_1} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> {} => { Iterator(Vec<T>), <Vec<T> as Iterator>::Item = T }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> { Iterator(T), <T as Iterator>::Item = Foo } => { <T as Iterator>::Item = Foo }",
    ).assert_ok(
        expect_test::expect!["{Constraints { env: Env { variables: [!ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]
    );

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> exists<U> { Iterator(T) } => { <T as Iterator>::Item = U }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => <!ty_1 as Iterator>::Item} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> { Iterator(T) } => { <T as Iterator>::Item = <T as Iterator>::Item }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> exists<U> { Iterator(T) } => { <T as Iterator>::Item = <U as Iterator>::Item }",
    ).assert_ok(
    expect_test::expect!["{Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => !ty_1} }, Constraints { env: Env { variables: [!ty_1, ?ty_3, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => Vec<<!ty_1 as Iterator>::Item>, ?ty_3 => <!ty_1 as Iterator>::Item} }}"]);
}

Source location: tests/projection.rs:44

#[test]
fn normalize_basic() {
    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> exists<U> {} => { <Vec<T> as Iterator>::Item = U }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => <Vec<!ty_1> as Iterator>::Item} }, Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => !ty_1} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> {} => { Iterator(Vec<T>), <Vec<T> as Iterator>::Item = T }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> { Iterator(T), <T as Iterator>::Item = Foo } => { <T as Iterator>::Item = Foo }",
    ).assert_ok(
        expect_test::expect!["{Constraints { env: Env { variables: [!ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]
    );

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> exists<U> { Iterator(T) } => { <T as Iterator>::Item = U }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => <!ty_1 as Iterator>::Item} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> { Iterator(T) } => { <T as Iterator>::Item = <T as Iterator>::Item }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> exists<U> { Iterator(T) } => { <T as Iterator>::Item = <U as Iterator>::Item }",
    ).assert_ok(
    expect_test::expect!["{Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => !ty_1} }, Constraints { env: Env { variables: [!ty_1, ?ty_3, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => Vec<<!ty_1 as Iterator>::Item>, ?ty_3 => <!ty_1 as Iterator>::Item} }}"]);
}

Source location: tests/projection.rs:55

#[test]
fn normalize_basic() {
    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> exists<U> {} => { <Vec<T> as Iterator>::Item = U }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => <Vec<!ty_1> as Iterator>::Item} }, Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => !ty_1} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> {} => { Iterator(Vec<T>), <Vec<T> as Iterator>::Item = T }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> { Iterator(T), <T as Iterator>::Item = Foo } => { <T as Iterator>::Item = Foo }",
    ).assert_ok(
        expect_test::expect!["{Constraints { env: Env { variables: [!ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]
    );

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> exists<U> { Iterator(T) } => { <T as Iterator>::Item = U }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => <!ty_1 as Iterator>::Item} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> { Iterator(T) } => { <T as Iterator>::Item = <T as Iterator>::Item }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {} }}"]);

    test_where_clause(
        NORMALIZE_BASIC,
        "forall<T> exists<U> { Iterator(T) } => { <T as Iterator>::Item = <U as Iterator>::Item }",
    ).assert_ok(
    expect_test::expect!["{Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => !ty_1} }, Constraints { env: Env { variables: [!ty_1, ?ty_3, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => Vec<<!ty_1 as Iterator>::Item>, ?ty_3 => <!ty_1 as Iterator>::Item} }}"]);
}

Source location: tests/projection.rs:89

#[test]
fn normalize_into_iterator() {
    test_where_clause(
        NORMALIZE_INTO_ITERATOR,
        "forall<T> exists<U> {} => { <Vec<T> as IntoIterator>::Item = U }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => <Vec<!ty_1> as IntoIterator>::Item} }, Constraints { env: Env { variables: [!ty_1, ?ty_2], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_2 => !ty_1} }}"]);
}

Source location: tests/projection.rs:112

#[test]
fn projection_equality() {
    test_where_clause(
        PROJECTION_EQUALITY,
        "exists<U> {} => { Trait1(S), <S as Trait1<>>::Type = U }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => u32} }, Constraints { env: Env { variables: [?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => <S as Trait1>::Type} }}"]);

    test_where_clause(PROJECTION_EQUALITY, "exists<U> {} => { Trait2(S, U) }")
        .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => u32} }, Constraints { env: Env { variables: [?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => <S as Trait1>::Type} }}"]);
}

Source location: tests/projection.rs:115

#[test]
fn projection_equality() {
    test_where_clause(
        PROJECTION_EQUALITY,
        "exists<U> {} => { Trait1(S), <S as Trait1<>>::Type = U }",
    )
    .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => u32} }, Constraints { env: Env { variables: [?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => <S as Trait1>::Type} }}"]);

    test_where_clause(PROJECTION_EQUALITY, "exists<U> {} => { Trait2(S, U) }")
        .assert_ok(expect_test::expect!["{Constraints { env: Env { variables: [?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => u32} }, Constraints { env: Env { variables: [?ty_1], bias: Soundness, pending: [], allow_pending_outlives: false }, known_true: true, substitution: {?ty_1 => <S as Trait1>::Type} }}"]);
}