48 lines
1022 B
Rust
48 lines
1022 B
Rust
//@ run-pass
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#![allow(dead_code, enum_intrinsics_non_enums)]
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#![feature(variant_count)]
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#![feature(never_type)]
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use std::mem::variant_count;
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enum Void {}
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enum Foo {
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A,
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B,
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C,
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}
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enum Bar {
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A,
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B,
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C,
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D(usize),
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E { field_1: usize, field_2: Foo },
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}
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struct Baz {
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a: u32,
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b: *const u8,
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}
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const TEST_VOID: usize = variant_count::<Void>();
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const TEST_FOO: usize = variant_count::<Foo>();
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const TEST_BAR: usize = variant_count::<Bar>();
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const NO_ICE_STRUCT: usize = variant_count::<Baz>();
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const NO_ICE_BOOL: usize = variant_count::<bool>();
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const NO_ICE_PRIM: usize = variant_count::<*const u8>();
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fn main() {
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assert_eq!(TEST_VOID, 0);
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assert_eq!(TEST_FOO, 3);
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assert_eq!(TEST_BAR, 5);
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assert_eq!(variant_count::<Void>(), 0);
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assert_eq!(variant_count::<Foo>(), 3);
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assert_eq!(variant_count::<Bar>(), 5);
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assert_eq!(variant_count::<Option<char>>(), 2);
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assert_eq!(variant_count::<Option<!>>(), 2);
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assert_eq!(variant_count::<Result<!, !>>(), 2);
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}
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