diff options
Diffstat (limited to 'src/test/ui/lint/lint-enum-intrinsics-non-enums.rs')
-rw-r--r-- | src/test/ui/lint/lint-enum-intrinsics-non-enums.rs | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/src/test/ui/lint/lint-enum-intrinsics-non-enums.rs b/src/test/ui/lint/lint-enum-intrinsics-non-enums.rs new file mode 100644 index 000000000..8ad337064 --- /dev/null +++ b/src/test/ui/lint/lint-enum-intrinsics-non-enums.rs @@ -0,0 +1,67 @@ +// Test the enum_intrinsics_non_enums lint. + +#![feature(variant_count)] + +use std::mem::{discriminant, variant_count}; + +enum SomeEnum { + A, + B, +} + +struct SomeStruct; + +fn generic_discriminant<T>(v: &T) { + discriminant::<T>(v); +} + +fn generic_variant_count<T>() -> usize { + variant_count::<T>() +} + +fn test_discriminant() { + discriminant(&SomeEnum::A); + generic_discriminant(&SomeEnum::B); + + discriminant(&()); + //~^ error: the return value of `mem::discriminant` is unspecified when called with a non-enum type + + discriminant(&&SomeEnum::B); + //~^ error: the return value of `mem::discriminant` is unspecified when called with a non-enum type + + discriminant(&SomeStruct); + //~^ error: the return value of `mem::discriminant` is unspecified when called with a non-enum type + + discriminant(&123u32); + //~^ error: the return value of `mem::discriminant` is unspecified when called with a non-enum type + + discriminant(&&123i8); + //~^ error: the return value of `mem::discriminant` is unspecified when called with a non-enum type +} + +fn test_variant_count() { + variant_count::<SomeEnum>(); + generic_variant_count::<SomeEnum>(); + + variant_count::<&str>(); + //~^ error: the return value of `mem::variant_count` is unspecified when called with a non-enum type + + variant_count::<*const u8>(); + //~^ error: the return value of `mem::variant_count` is unspecified when called with a non-enum type + + variant_count::<()>(); + //~^ error: the return value of `mem::variant_count` is unspecified when called with a non-enum type + + variant_count::<&SomeEnum>(); + //~^ error: the return value of `mem::variant_count` is unspecified when called with a non-enum type +} + +fn main() { + test_discriminant(); + test_variant_count(); + + // The lint ignores cases where the type is generic, so these should be + // allowed even though their return values are unspecified + generic_variant_count::<SomeStruct>(); + generic_discriminant::<SomeStruct>(&SomeStruct); +} |