54 lines
1.2 KiB
Rust
54 lines
1.2 KiB
Rust
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// run-pass
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// This file checks that `PhantomData` is considered structurally matchable.
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use std::marker::PhantomData;
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fn main() {
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let mut count = 0;
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// A type which is not structurally matchable:
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struct NotSM;
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// And one that is:
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#[derive(PartialEq, Eq)]
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struct SM;
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// Check that SM is #[structural_match]:
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const CSM: SM = SM;
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match SM {
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CSM => count += 1,
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};
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// Check that PhantomData<T> is #[structural_match] even if T is not.
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const CPD1: PhantomData<NotSM> = PhantomData;
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match PhantomData {
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CPD1 => count += 1,
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};
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// Check that PhantomData<T> is #[structural_match] when T is.
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const CPD2: PhantomData<SM> = PhantomData;
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match PhantomData {
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CPD2 => count += 1,
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};
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// Check that a type which has a PhantomData is `#[structural_match]`.
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#[derive(PartialEq, Eq, Default)]
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struct Foo {
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alpha: PhantomData<NotSM>,
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beta: PhantomData<SM>,
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}
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const CFOO: Foo = Foo {
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alpha: PhantomData,
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beta: PhantomData,
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};
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match Foo::default() {
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CFOO => count += 1,
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};
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// Final count must be 4 now if all
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assert_eq!(count, 4);
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}
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