diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs index 4e0f455e36238..6596311bdf364 100644 --- a/src/librustc_typeck/check/mod.rs +++ b/src/librustc_typeck/check/mod.rs @@ -3252,6 +3252,16 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> { } Def::Struct(..) | Def::Union(..) | Def::TyAlias(..) | Def::AssociatedTy(..) | Def::SelfTy(..) => { + match def { + Def::AssociatedTy(..) | Def::SelfTy(..) + if !self.tcx.sess.features.borrow().more_struct_aliases => { + emit_feature_err(&self.tcx.sess.parse_sess, + "more_struct_aliases", path.span, GateIssue::Language, + "`Self` and associated types in struct \ + expressions and patterns are unstable"); + } + _ => {} + } match ty.sty { ty::TyAdt(adt, substs) if !adt.is_enum() => { Some((adt.struct_variant(), adt.did, substs)) diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs index 129e4a8233803..69dfe8e862095 100644 --- a/src/libsyntax/feature_gate.rs +++ b/src/libsyntax/feature_gate.rs @@ -309,6 +309,9 @@ declare_features! ( // Allows field shorthands (`x` meaning `x: x`) in struct literal expressions. (active, field_init_shorthand, "1.14.0", Some(37340)), + + // Allows using `Self` and associated types in struct expressions and patterns. + (active, more_struct_aliases, "1.14.0", Some(37544)), ); declare_features! ( diff --git a/src/test/compile-fail/struct-path-associated-type.rs b/src/test/compile-fail/struct-path-associated-type.rs index 660ac44ce0b53..ecaf269fcb1ae 100644 --- a/src/test/compile-fail/struct-path-associated-type.rs +++ b/src/test/compile-fail/struct-path-associated-type.rs @@ -8,6 +8,8 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. +#![feature(more_struct_aliases)] + struct S; trait Tr { diff --git a/src/test/compile-fail/struct-path-self-feature-gate.rs b/src/test/compile-fail/struct-path-self-feature-gate.rs new file mode 100644 index 0000000000000..a2050182a7e30 --- /dev/null +++ b/src/test/compile-fail/struct-path-self-feature-gate.rs @@ -0,0 +1,29 @@ +// Copyright 2016 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +struct S; + +trait Tr { + type A; +} + +fn f>() { + let _ = T::A {}; + //~^ ERROR `Self` and associated types in struct expressions and patterns are unstable +} + +impl S { + fn f() { + let _ = Self {}; + //~^ ERROR `Self` and associated types in struct expressions and patterns are unstable + } +} + +fn main() {} diff --git a/src/test/compile-fail/struct-path-self-type-mismatch.rs b/src/test/compile-fail/struct-path-self-type-mismatch.rs index f694e7d277c7f..8352bd6751f50 100644 --- a/src/test/compile-fail/struct-path-self-type-mismatch.rs +++ b/src/test/compile-fail/struct-path-self-type-mismatch.rs @@ -8,6 +8,8 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. +#![feature(more_struct_aliases)] + struct Foo { inner: A } trait Bar { fn bar(); } diff --git a/src/test/compile-fail/struct-path-self.rs b/src/test/compile-fail/struct-path-self.rs index 067d6ac22dc6f..aeac199227b75 100644 --- a/src/test/compile-fail/struct-path-self.rs +++ b/src/test/compile-fail/struct-path-self.rs @@ -8,6 +8,8 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. +#![feature(more_struct_aliases)] + struct S; trait Tr { diff --git a/src/test/run-pass/struct-path-associated-type.rs b/src/test/run-pass/struct-path-associated-type.rs index b033ed5c80210..292761dfd005f 100644 --- a/src/test/run-pass/struct-path-associated-type.rs +++ b/src/test/run-pass/struct-path-associated-type.rs @@ -8,6 +8,8 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. +#![feature(more_struct_aliases)] + struct S { a: T, b: U, diff --git a/src/test/run-pass/struct-path-self.rs b/src/test/run-pass/struct-path-self.rs index c7a282c2a2fa0..b569ab62c1bfa 100644 --- a/src/test/run-pass/struct-path-self.rs +++ b/src/test/run-pass/struct-path-self.rs @@ -8,6 +8,8 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. +#![feature(more_struct_aliases)] + use std::ops::Add; struct S {