4 files changed, 183 insertions, 0 deletions
diff --git a/tests/ui/rfcs/rfc-0000-never_patterns/check.rs b/tests/ui/rfcs/rfc-0000-never_patterns/check.rs
new file mode 100644
index 000000000..e29811224
--- /dev/null
+++ b/tests/ui/rfcs/rfc-0000-never_patterns/check.rs
@@ -0,0 +1,33 @@
+#![feature(never_patterns)]
+#![allow(incomplete_features)]
+
+enum Void {}
+
+fn main() {}
+
+macro_rules! never {
+    () => { ! }
+}
+
+fn no_arms_or_guards(x: Void) {
+    match None::<Void> {
+        Some(!) => {}
+        //~^ ERROR a never pattern is always unreachable
+        None => {}
+    }
+    match None::<Void> {
+        Some(!) if true,
+        //~^ ERROR guard on a never pattern
+        None => {}
+    }
+    match None::<Void> {
+        Some(!) if true => {}
+        //~^ ERROR a never pattern is always unreachable
+        None => {}
+    }
+    match None::<Void> {
+        Some(never!()) => {},
+        //~^ ERROR a never pattern is always unreachable
+        None => {}
+    }
+}
diff --git a/tests/ui/rfcs/rfc-0000-never_patterns/check.stderr b/tests/ui/rfcs/rfc-0000-never_patterns/check.stderr
new file mode 100644
index 000000000..bfbc7a1b5
--- /dev/null
+++ b/tests/ui/rfcs/rfc-0000-never_patterns/check.stderr
@@ -0,0 +1,35 @@
+error: a never pattern is always unreachable
+  --> $DIR/check.rs:14:20
+   |
+LL |         Some(!) => {}
+   |                    ^^
+   |                    |
+   |                    this will never be executed
+   |                    help: remove this expression
+
+error: a guard on a never pattern will never be run
+  --> $DIR/check.rs:19:20
+   |
+LL |         Some(!) if true,
+   |                    ^^^^ help: remove this guard
+
+error: a never pattern is always unreachable
+  --> $DIR/check.rs:24:28
+   |
+LL |         Some(!) if true => {}
+   |                            ^^
+   |                            |
+   |                            this will never be executed
+   |                            help: remove this expression
+
+error: a never pattern is always unreachable
+  --> $DIR/check.rs:29:27
+   |
+LL |         Some(never!()) => {},
+   |                           ^^
+   |                           |
+   |                           this will never be executed
+   |                           help: remove this expression
+
+error: aborting due to 4 previous errors
+
diff --git a/tests/ui/rfcs/rfc-0000-never_patterns/parse.rs b/tests/ui/rfcs/rfc-0000-never_patterns/parse.rs
new file mode 100644
index 000000000..1b23e60e0
--- /dev/null
+++ b/tests/ui/rfcs/rfc-0000-never_patterns/parse.rs
@@ -0,0 +1,71 @@
+#![feature(never_patterns)]
+#![allow(incomplete_features)]
+
+enum Void {}
+
+fn main() {}
+
+macro_rules! never {
+    () => { ! }
+}
+
+fn parse(x: Void) {
+    match None::<Void> {
+        None => {}
+        Some(!),
+    }
+    match None::<Void> {
+        Some(!),
+        None => {}
+    }
+    match None::<Void> {
+        None => {}
+        Some(!)
+    }
+    match None::<Void> {
+        Some(!)
+        //~^ ERROR expected `,` following `match` arm
+        None => {}
+    }
+    match None::<Void> {
+        Some(!) if true
+        //~^ ERROR expected `,` following `match` arm
+        //~| ERROR guard on a never pattern
+        None => {}
+    }
+    match None::<Void> {
+        Some(!) if true,
+        //~^ ERROR guard on a never pattern
+        None => {}
+    }
+    match None::<Void> {
+        Some(!) <=
+        //~^ ERROR expected one of
+    }
+    match x {
+        never!(),
+    }
+    match x {
+        never!() if true,
+        //~^ ERROR guard on a never pattern
+    }
+    match x {
+        never!()
+    }
+    match &x {
+        &never!(),
+    }
+    match None::<Void> {
+        Some(never!()),
+        None => {}
+    }
+    match x { ! }
+    match &x { &! }
+
+    let res: Result<bool, Void> = Ok(false);
+    let Ok(_) = res;
+    let Ok(_) | Err(!) = &res; // Disallowed; see #82048.
+    //~^ ERROR top-level or-patterns are not allowed in `let` bindings
+    let (Ok(_) | Err(!)) = &res;
+    let (Ok(_) | Err(&!)) = res.as_ref();
+}
diff --git a/tests/ui/rfcs/rfc-0000-never_patterns/parse.stderr b/tests/ui/rfcs/rfc-0000-never_patterns/parse.stderr
new file mode 100644
index 000000000..e81a13a39
--- /dev/null
+++ b/tests/ui/rfcs/rfc-0000-never_patterns/parse.stderr
@@ -0,0 +1,44 @@
+error: expected `,` following `match` arm
+  --> $DIR/parse.rs:26:16
+   |
+LL |         Some(!)
+   |                ^ help: missing a comma here to end this `match` arm: `,`
+
+error: expected `,` following `match` arm
+  --> $DIR/parse.rs:31:24
+   |
+LL |         Some(!) if true
+   |                        ^ help: missing a comma here to end this `match` arm: `,`
+
+error: expected one of `,`, `=>`, `if`, `|`, or `}`, found `<=`
+  --> $DIR/parse.rs:42:17
+   |
+LL |         Some(!) <=
+   |                 ^^ expected one of `,`, `=>`, `if`, `|`, or `}`
+
+error: top-level or-patterns are not allowed in `let` bindings
+  --> $DIR/parse.rs:67:9
+   |
+LL |     let Ok(_) | Err(!) = &res; // Disallowed; see #82048.
+   |         ^^^^^^^^^^^^^^ help: wrap the pattern in parentheses: `(Ok(_) | Err(!))`
+
+error: a guard on a never pattern will never be run
+  --> $DIR/parse.rs:31:20
+   |
+LL |         Some(!) if true
+   |                    ^^^^ help: remove this guard
+
+error: a guard on a never pattern will never be run
+  --> $DIR/parse.rs:37:20
+   |
+LL |         Some(!) if true,
+   |                    ^^^^ help: remove this guard
+
+error: a guard on a never pattern will never be run
+  --> $DIR/parse.rs:49:21
+   |
+LL |         never!() if true,
+   |                     ^^^^ help: remove this guard
+
+error: aborting due to 7 previous errors
+