1 files changed, 180 insertions, 0 deletions
diff --git a/tests/ui/match/overeager-sub-match-pruning-13027.rs b/tests/ui/match/overeager-sub-match-pruning-13027.rs
new file mode 100644
index 00000000000..c4feb697f7d
--- /dev/null
+++ b/tests/ui/match/overeager-sub-match-pruning-13027.rs
@@ -0,0 +1,180 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/13027
+
+//@ run-pass
+
+// Tests that match expression handles overlapped literal and range
+// properly in the presence of guard function.
+
+fn val() -> usize { 1 }
+
+static CONST: usize = 1;
+
+pub fn main() {
+    lit_shadow_range();
+    range_shadow_lit();
+    range_shadow_range();
+    multi_pats_shadow_lit();
+    multi_pats_shadow_range();
+    lit_shadow_multi_pats();
+    range_shadow_multi_pats();
+    misc();
+}
+
+fn lit_shadow_range() {
+    assert_eq!(2, match 1 {
+        1 if false => 1,
+        1..=2 => 2,
+        _ => 3
+    });
+
+    let x = 0;
+    assert_eq!(2, match x+1 {
+        0 => 0,
+        1 if false => 1,
+        1..=2 => 2,
+        _ => 3
+    });
+
+    assert_eq!(2, match val() {
+        1 if false => 1,
+        1..=2 => 2,
+        _ => 3
+    });
+
+    assert_eq!(2, match CONST {
+        0 => 0,
+        1 if false => 1,
+        1..=2 => 2,
+        _ => 3
+    });
+
+    // value is out of the range of second arm, should match wildcard pattern
+    assert_eq!(3, match 3 {
+        1 if false => 1,
+        1..=2 => 2,
+        _ => 3
+    });
+}
+
+fn range_shadow_lit() {
+    assert_eq!(2, match 1 {
+        1..=2 if false => 1,
+        1 => 2,
+        _ => 3
+    });
+
+    let x = 0;
+    assert_eq!(2, match x+1 {
+        0 => 0,
+        1..=2 if false => 1,
+        1 => 2,
+        _ => 3
+    });
+
+    assert_eq!(2, match val() {
+        1..=2 if false => 1,
+        1 => 2,
+        _ => 3
+    });
+
+    assert_eq!(2, match CONST {
+        0 => 0,
+        1..=2 if false => 1,
+        1 => 2,
+        _ => 3
+    });
+
+    // ditto
+    assert_eq!(3, match 3 {
+        1..=2 if false => 1,
+        1 => 2,
+        _ => 3
+    });
+}
+
+fn range_shadow_range() {
+    assert_eq!(2, match 1 {
+        0..=2 if false => 1,
+        1..=3 => 2,
+        _ => 3,
+    });
+
+    let x = 0;
+    assert_eq!(2, match x+1 {
+        100 => 0,
+        0..=2 if false => 1,
+        1..=3 => 2,
+        _ => 3,
+    });
+
+    assert_eq!(2, match val() {
+        0..=2 if false => 1,
+        1..=3 => 2,
+        _ => 3,
+    });
+
+    assert_eq!(2, match CONST {
+        100 => 0,
+        0..=2 if false => 1,
+        1..=3 => 2,
+        _ => 3,
+    });
+
+    // ditto
+    assert_eq!(3, match 5 {
+        0..=2 if false => 1,
+        1..=3 => 2,
+        _ => 3,
+    });
+}
+
+fn multi_pats_shadow_lit() {
+    assert_eq!(2, match 1 {
+        100 => 0,
+        0 | 1..=10 if false => 1,
+        1 => 2,
+        _ => 3,
+    });
+}
+
+fn multi_pats_shadow_range() {
+    assert_eq!(2, match 1 {
+        100 => 0,
+        0 | 1..=10 if false => 1,
+        1..=3 => 2,
+        _ => 3,
+    });
+}
+
+fn lit_shadow_multi_pats() {
+    assert_eq!(2, match 1 {
+        100 => 0,
+        1 if false => 1,
+        0 | 1..=10 => 2,
+        _ => 3,
+    });
+}
+
+fn range_shadow_multi_pats() {
+    assert_eq!(2, match 1 {
+        100 => 0,
+        1..=3 if false => 1,
+        0 | 1..=10 => 2,
+        _ => 3,
+    });
+}
+
+fn misc() {
+    enum Foo {
+        Bar(#[allow(dead_code)] usize, bool)
+    }
+    // This test basically mimics how trace_macros! macro is implemented,
+    // which is a rare combination of vector patterns, multiple wild-card
+    // patterns and guard functions.
+    let r = match [Foo::Bar(0, false)] {
+        [Foo::Bar(_, pred)] if pred => 1,
+        [Foo::Bar(_, pred)] if !pred => 2,
+        _ => 0,
+    };
+    assert_eq!(2, r);
+}