Merge remote-tracking branch 'rust-lang/master' into hermit

16 files changed, 271 insertions, 8 deletions

diff --git a/src/test/ui/pattern/usefulness/match-byte-array-patterns-2.stderr b/src/test/ui/pattern/usefulness/match-byte-array-patterns-2.stderr
index d53e2e25b3d..6e52072e3bf 100644
--- a/src/test/ui/pattern/usefulness/match-byte-array-patterns-2.stderr
+++ b/src/test/ui/pattern/usefulness/match-byte-array-patterns-2.stderr
@@ -6,11 +6,11 @@ LL |     match buf {
    |
    = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
 
-error[E0004]: non-exhaustive patterns: `&[]`, `&[_]`, `&[_, _]` and 3 more not covered
+error[E0004]: non-exhaustive patterns: `&[..]` not covered
   --> $DIR/match-byte-array-patterns-2.rs:10:11
    |
 LL |     match buf {
-   |           ^^^ patterns `&[]`, `&[_]`, `&[_, _]` and 3 more not covered
+   |           ^^^ pattern `&[..]` not covered
    |
    = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
 
diff --git a/src/test/ui/pattern/usefulness/match-slice-patterns.rs b/src/test/ui/pattern/usefulness/match-slice-patterns.rs
index afbeb61e441..af7fd53a1f1 100644
--- a/src/test/ui/pattern/usefulness/match-slice-patterns.rs
+++ b/src/test/ui/pattern/usefulness/match-slice-patterns.rs
@@ -2,7 +2,7 @@
 
 fn check(list: &[Option<()>]) {
     match list {
-    //~^ ERROR `&[_, Some(_), None, _]` not covered
+    //~^ ERROR `&[_, Some(_), .., None, _]` not covered
         &[] => {},
         &[_] => {},
         &[_, _] => {},
diff --git a/src/test/ui/pattern/usefulness/match-slice-patterns.stderr b/src/test/ui/pattern/usefulness/match-slice-patterns.stderr
index 24769db34c9..72ae5d5fe3b 100644
--- a/src/test/ui/pattern/usefulness/match-slice-patterns.stderr
+++ b/src/test/ui/pattern/usefulness/match-slice-patterns.stderr
@@ -1,8 +1,8 @@
-error[E0004]: non-exhaustive patterns: `&[_, Some(_), None, _]` not covered
+error[E0004]: non-exhaustive patterns: `&[_, Some(_), .., None, _]` not covered
   --> $DIR/match-slice-patterns.rs:4:11
    |
 LL |     match list {
-   |           ^^^^ pattern `&[_, Some(_), None, _]` not covered
+   |           ^^^^ pattern `&[_, Some(_), .., None, _]` not covered
    |
    = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
 
diff --git a/src/test/ui/pattern/usefulness/non-exhaustive-match.rs b/src/test/ui/pattern/usefulness/non-exhaustive-match.rs
index 0e5a9203c5f..bfca5352353 100644
--- a/src/test/ui/pattern/usefulness/non-exhaustive-match.rs
+++ b/src/test/ui/pattern/usefulness/non-exhaustive-match.rs
@@ -44,7 +44,7 @@ fn main() {
     }
     let vec = vec![0.5f32];
     let vec: &[f32] = &vec;
-    match *vec { //~ ERROR non-exhaustive patterns: `[_, _, _, _]` not covered
+    match *vec { //~ ERROR non-exhaustive patterns: `[_, _, _, _, ..]` not covered
         [0.1, 0.2, 0.3] => (),
         [0.1, 0.2] => (),
         [0.1] => (),
diff --git a/src/test/ui/pattern/usefulness/non-exhaustive-match.stderr b/src/test/ui/pattern/usefulness/non-exhaustive-match.stderr
index 5dba05e1642..577867e4e71 100644
--- a/src/test/ui/pattern/usefulness/non-exhaustive-match.stderr
+++ b/src/test/ui/pattern/usefulness/non-exhaustive-match.stderr
@@ -66,11 +66,11 @@ LL |     match *vec {
    |
    = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
 
-error[E0004]: non-exhaustive patterns: `[_, _, _, _]` not covered
+error[E0004]: non-exhaustive patterns: `[_, _, _, _, ..]` not covered
   --> $DIR/non-exhaustive-match.rs:47:11
    |
 LL |     match *vec {
-   |           ^^^^ pattern `[_, _, _, _]` not covered
+   |           ^^^^ pattern `[_, _, _, _, ..]` not covered
    |
    = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
 
diff --git a/src/test/ui/pattern/slice-pattern-const-2.rs b/src/test/ui/pattern/usefulness/slice-pattern-const-2.rs
index a36c550f530..a36c550f530 100644
--- a/src/test/ui/pattern/slice-pattern-const-2.rs
+++ b/src/test/ui/pattern/usefulness/slice-pattern-const-2.rs
diff --git a/src/test/ui/pattern/slice-pattern-const-2.stderr b/src/test/ui/pattern/usefulness/slice-pattern-const-2.stderr
index 0c7401269df..0c7401269df 100644
--- a/src/test/ui/pattern/slice-pattern-const-2.stderr
+++ b/src/test/ui/pattern/usefulness/slice-pattern-const-2.stderr
diff --git a/src/test/ui/pattern/slice-pattern-const-3.rs b/src/test/ui/pattern/usefulness/slice-pattern-const-3.rs
index 8805c43ba02..8805c43ba02 100644
--- a/src/test/ui/pattern/slice-pattern-const-3.rs
+++ b/src/test/ui/pattern/usefulness/slice-pattern-const-3.rs
diff --git a/src/test/ui/pattern/slice-pattern-const-3.stderr b/src/test/ui/pattern/usefulness/slice-pattern-const-3.stderr
index eab4fc3f086..eab4fc3f086 100644
--- a/src/test/ui/pattern/slice-pattern-const-3.stderr
+++ b/src/test/ui/pattern/usefulness/slice-pattern-const-3.stderr
diff --git a/src/test/ui/pattern/slice-pattern-const.rs b/src/test/ui/pattern/usefulness/slice-pattern-const.rs
index f0a04513f91..f0a04513f91 100644
--- a/src/test/ui/pattern/slice-pattern-const.rs
+++ b/src/test/ui/pattern/usefulness/slice-pattern-const.rs
diff --git a/src/test/ui/pattern/slice-pattern-const.stderr b/src/test/ui/pattern/usefulness/slice-pattern-const.stderr
index 2dd10a0478a..2dd10a0478a 100644
--- a/src/test/ui/pattern/slice-pattern-const.stderr
+++ b/src/test/ui/pattern/usefulness/slice-pattern-const.stderr
diff --git a/src/test/ui/pattern/usefulness/slice-patterns-exhaustiveness.rs b/src/test/ui/pattern/usefulness/slice-patterns-exhaustiveness.rs
new file mode 100644
index 00000000000..86cdf160618
--- /dev/null
+++ b/src/test/ui/pattern/usefulness/slice-patterns-exhaustiveness.rs
@@ -0,0 +1,75 @@
+#![feature(slice_patterns)]
+
+fn main() {
+    let s: &[bool] = &[true; 0];
+    let s1: &[bool; 1] = &[false; 1];
+    let s2: &[bool; 2] = &[false; 2];
+    let s3: &[bool; 3] = &[false; 3];
+
+    match s1 {
+        [true, ..] => {}
+        [.., false] => {}
+    }
+    match s2 {
+    //~^ ERROR `&[false, true]` not covered
+        [true, ..] => {}
+        [.., false] => {}
+    }
+    match s3 {
+    //~^ ERROR `&[false, _, true]` not covered
+        [true, ..] => {}
+        [.., false] => {}
+    }
+    match s {
+    //~^ ERROR `&[false, .., true]` not covered
+        [] => {}
+        [true, ..] => {}
+        [.., false] => {}
+    }
+
+    match s3 {
+    //~^ ERROR `&[false, _, _]` not covered
+        [true, .., true] => {}
+    }
+    match s {
+    //~^ ERROR `&[_, ..]` not covered
+        [] => {}
+    }
+    match s {
+    //~^ ERROR `&[_, _, ..]` not covered
+        [] => {}
+        [_] => {}
+    }
+    match s {
+    //~^ ERROR `&[false, ..]` not covered
+        [] => {}
+        [true, ..] => {}
+    }
+    match s {
+    //~^ ERROR `&[false, _, ..]` not covered
+        [] => {}
+        [_] => {}
+        [true, ..] => {}
+    }
+    match s {
+    //~^ ERROR `&[_, .., false]` not covered
+        [] => {}
+        [_] => {}
+        [.., true] => {}
+    }
+
+    match s {
+    //~^ ERROR `&[_, _, .., true]` not covered
+        [] => {}
+        [_] => {}
+        [_, _] => {}
+        [.., false] => {}
+    }
+    match s {
+    //~^ ERROR `&[true, _, .., _]` not covered
+        [] => {}
+        [_] => {}
+        [_, _] => {}
+        [false, .., false] => {}
+    }
+}
diff --git a/src/test/ui/pattern/usefulness/slice-patterns-exhaustiveness.stderr b/src/test/ui/pattern/usefulness/slice-patterns-exhaustiveness.stderr
new file mode 100644
index 00000000000..1391b520556
--- /dev/null
+++ b/src/test/ui/pattern/usefulness/slice-patterns-exhaustiveness.stderr
@@ -0,0 +1,91 @@
+error[E0004]: non-exhaustive patterns: `&[false, true]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:13:11
+   |
+LL |     match s2 {
+   |           ^^ pattern `&[false, true]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: `&[false, _, true]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:18:11
+   |
+LL |     match s3 {
+   |           ^^ pattern `&[false, _, true]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: `&[false, .., true]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:23:11
+   |
+LL |     match s {
+   |           ^ pattern `&[false, .., true]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: `&[false, _, _]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:30:11
+   |
+LL |     match s3 {
+   |           ^^ pattern `&[false, _, _]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: `&[_, ..]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:34:11
+   |
+LL |     match s {
+   |           ^ pattern `&[_, ..]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: `&[_, _, ..]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:38:11
+   |
+LL |     match s {
+   |           ^ pattern `&[_, _, ..]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: `&[false, ..]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:43:11
+   |
+LL |     match s {
+   |           ^ pattern `&[false, ..]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: `&[false, _, ..]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:48:11
+   |
+LL |     match s {
+   |           ^ pattern `&[false, _, ..]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: `&[_, .., false]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:54:11
+   |
+LL |     match s {
+   |           ^ pattern `&[_, .., false]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: `&[_, _, .., true]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:61:11
+   |
+LL |     match s {
+   |           ^ pattern `&[_, _, .., true]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: `&[true, _, .., _]` not covered
+  --> $DIR/slice-patterns-exhaustiveness.rs:68:11
+   |
+LL |     match s {
+   |           ^ pattern `&[true, _, .., _]` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error: aborting due to 11 previous errors
+
+For more information about this error, try `rustc --explain E0004`.
diff --git a/src/test/ui/pattern/usefulness/slice-patterns-irrefutable.rs b/src/test/ui/pattern/usefulness/slice-patterns-irrefutable.rs
new file mode 100644
index 00000000000..3b716bae772
--- /dev/null
+++ b/src/test/ui/pattern/usefulness/slice-patterns-irrefutable.rs
@@ -0,0 +1,27 @@
+// check-pass
+#![feature(slice_patterns)]
+
+fn main() {
+    let s: &[bool] = &[true; 0];
+    let s0: &[bool; 0] = &[];
+    let s1: &[bool; 1] = &[false; 1];
+    let s2: &[bool; 2] = &[false; 2];
+
+    let [] = s0;
+    let [_] = s1;
+    let [_, _] = s2;
+
+    let [..] = s;
+    let [..] = s0;
+    let [..] = s1;
+    let [..] = s2;
+
+    let [_, ..] = s1;
+    let [.., _] = s1;
+    let [_, ..] = s2;
+    let [.., _] = s2;
+
+    let [_, _, ..] = s2;
+    let [_, .., _] = s2;
+    let [.., _, _] = s2;
+}
diff --git a/src/test/ui/pattern/usefulness/slice-patterns-reachability.rs b/src/test/ui/pattern/usefulness/slice-patterns-reachability.rs
new file mode 100644
index 00000000000..35d9dc91aee
--- /dev/null
+++ b/src/test/ui/pattern/usefulness/slice-patterns-reachability.rs
@@ -0,0 +1,26 @@
+#![feature(slice_patterns)]
+#![deny(unreachable_patterns)]
+
+fn main() {
+    let s: &[bool] = &[true; 0];
+
+    match s {
+        [true, ..] => {}
+        [true, ..] => {} //~ ERROR unreachable pattern
+        [true] => {} //~ ERROR unreachable pattern
+        [..] => {}
+    }
+    match s {
+        [.., true] => {}
+        [.., true] => {} //~ ERROR unreachable pattern
+        [true] => {} //~ ERROR unreachable pattern
+        [..] => {}
+    }
+    match s {
+        [false, .., true] => {}
+        [false, .., true] => {} //~ ERROR unreachable pattern
+        [false, true] => {} //~ ERROR unreachable pattern
+        [false] => {}
+        [..] => {}
+    }
+}
diff --git a/src/test/ui/pattern/usefulness/slice-patterns-reachability.stderr b/src/test/ui/pattern/usefulness/slice-patterns-reachability.stderr
new file mode 100644
index 00000000000..333ce170283
--- /dev/null
+++ b/src/test/ui/pattern/usefulness/slice-patterns-reachability.stderr
@@ -0,0 +1,44 @@
+error: unreachable pattern
+  --> $DIR/slice-patterns-reachability.rs:9:9
+   |
+LL |         [true, ..] => {}
+   |         ^^^^^^^^^^
+   |
+note: lint level defined here
+  --> $DIR/slice-patterns-reachability.rs:2:9
+   |
+LL | #![deny(unreachable_patterns)]
+   |         ^^^^^^^^^^^^^^^^^^^^
+
+error: unreachable pattern
+  --> $DIR/slice-patterns-reachability.rs:10:9
+   |
+LL |         [true] => {}
+   |         ^^^^^^
+
+error: unreachable pattern
+  --> $DIR/slice-patterns-reachability.rs:15:9
+   |
+LL |         [.., true] => {}
+   |         ^^^^^^^^^^
+
+error: unreachable pattern
+  --> $DIR/slice-patterns-reachability.rs:16:9
+   |
+LL |         [true] => {}
+   |         ^^^^^^
+
+error: unreachable pattern
+  --> $DIR/slice-patterns-reachability.rs:21:9
+   |
+LL |         [false, .., true] => {}
+   |         ^^^^^^^^^^^^^^^^^
+
+error: unreachable pattern
+  --> $DIR/slice-patterns-reachability.rs:22:9
+   |
+LL |         [false, true] => {}
+   |         ^^^^^^^^^^^^^
+
+error: aborting due to 6 previous errors
+