Stabilize unit tests with non-() return type

src/libsyntax/feature_gate.rs

@@ -398,9 +398,6 @@ declare_features! (
     // `foo.rs` as an alternative to `foo/mod.rs`
     (active, non_modrs_mods, "1.24.0", Some(44660), Some(Edition::Edition2018)),
 
-    // Termination trait in tests (RFC 1937)
-    (active, termination_trait_test, "1.24.0", Some(48854), Some(Edition::Edition2018)),
-
     // `extern` in paths
     (active, extern_in_paths, "1.23.0", Some(44660), None),
 
@@ -475,6 +472,9 @@ declare_features! (
 
     // 'a: { break 'a; }
     (active, label_break_value, "1.28.0", Some(48594), None),
+
+    // Termination trait in tests (RFC 1937)
+    (accepted, termination_trait_test, "1.28.0", Some(48854), Some(Edition::Edition2018)),
 );
 
 declare_features! (

src/libsyntax/test.rs

@@ -351,15 +351,15 @@ fn is_test_fn(cx: &TestCtxt, i: &ast::Item) -> bool {
                     return No(BadTestSignature::NoArgumentsAllowed);
                 }
 
-                match (has_output, cx.features.termination_trait_test, has_should_panic_attr) {
-                    (true, true, true) => No(BadTestSignature::ShouldPanicOnlyWithNoArgs),
-                    (true, true, false) => if generics.is_parameterized() {
+                match (has_output, has_should_panic_attr) {
+                    (true, true) => No(BadTestSignature::ShouldPanicOnlyWithNoArgs),
+                    (true, false) => if generics.is_parameterized() {
                         No(BadTestSignature::WrongTypeSignature)
                     } else {
                         Yes
                     },
-                    (true, false, _) => No(BadTestSignature::WrongTypeSignature),
-                    (false, _, _) => Yes
+                    (true, _) => No(BadTestSignature::WrongTypeSignature),
+                    (false, _) => Yes
                 }
             }
             _ => No(BadTestSignature::NotEvenAFunction),
@@ -398,28 +398,9 @@ fn is_bench_fn(cx: &TestCtxt, i: &ast::Item) -> bool {
     fn has_bench_signature(cx: &TestCtxt, i: &ast::Item) -> bool {
         match i.node {
             ast::ItemKind::Fn(ref decl, _, _, _, ref generics, _) => {
-                let input_cnt = decl.inputs.len();
-
-                // If the termination trait is active, the compiler will check that the output
-                // type implements the `Termination` trait as `libtest` enforces that.
-                let output_matches = if cx.features.termination_trait_test {
-                    true
-                } else {
-                    let no_output = match decl.output {
-                        ast::FunctionRetTy::Default(..) => true,
-                        ast::FunctionRetTy::Ty(ref t) if t.node == ast::TyKind::Tup(vec![]) => true,
-                        _ => false
-                    };
-                    let tparm_cnt = generics.params.iter()
-                        .filter(|param| param.is_type_param())
-                        .count();
-
-                    no_output && tparm_cnt == 0
-                };
-
                 // NB: inadequate check, but we're running
                 // well before resolve, can't get too deep.
-                input_cnt == 1 && output_matches
+                decl.inputs.len() == 1
             }
             _ => false
         }
@@ -430,13 +411,8 @@ fn is_bench_fn(cx: &TestCtxt, i: &ast::Item) -> bool {
     if has_bench_attr && !has_bench_signature {
         let diag = cx.span_diagnostic;
 
-        if cx.features.termination_trait_test {
-            diag.span_err(i.span, "functions used as benches must have signature \
+        diag.span_err(i.span, "functions used as benches must have signature \
                                    `fn(&mut Bencher) -> impl Termination`");
-        } else {
-            diag.span_err(i.span, "functions used as benches must have signature \
-                                   `fn(&mut Bencher) -> ()`");
-        }
     }
 
     has_bench_attr && has_bench_signature

src/test/compile-fail/feature-gate-termination_trait_test.rs

@@ -1,22 +0,0 @@
-// Copyright 2017 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 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-// compile-flags: --test
-
-fn main() {}
-
-#[cfg(test)]
-mod tests {
-    #[test]
-    fn it_works() -> Result<(), ()> {
-    //~^ ERROR functions used as tests must have signature fn() -> ()
-        Ok(())
-    }
-}

src/test/ui/rfc-1937-termination-trait/termination-trait-in-test-should-panic.rs

@@ -10,7 +10,6 @@
 
 // compile-flags: --test
 
-#![feature(termination_trait_test)]
 #![feature(test)]
 
 extern crate test;

src/test/ui/rfc-1937-termination-trait/termination-trait-in-test.rs

@@ -11,7 +11,6 @@
 // compile-flags: --test
 // run-pass
 
-#![feature(termination_trait_test)]
 #![feature(test)]
 
 extern crate test;

src/test/ui/rfc-1937-termination-trait/termination-trait-test-wrong-type.rs

@@ -10,8 +10,6 @@
 
 // compile-flags: --test
 
-#![feature(termination_trait_test)]
-
 use std::num::ParseIntError;
 
 #[test]