From 6728240f36c7dd1ecb16d396c9c61933d2f01da9 Mon Sep 17 00:00:00 2001
From: Christiaan Dirkx <christiaan@dirkx.email>
Date: Sat, 7 Nov 2020 01:02:15 +0100
Subject: [PATCH] Test structural matching for all range types

Adds structural match tests for all range types.

Note: also adds the otherwise unrelated test `test_range_to_inclusive` for completeness
---
 library/core/tests/ops.rs | 48 ++++++++++++++++++++++++++++++++++++++-
 1 file changed, 47 insertions(+), 1 deletion(-)

diff --git a/library/core/tests/ops.rs b/library/core/tests/ops.rs
index 8f0cd3be4066e..e9d595e65e2b2 100644
--- a/library/core/tests/ops.rs
+++ b/library/core/tests/ops.rs
@@ -1,4 +1,4 @@
-use core::ops::{Bound, Range, RangeFrom, RangeFull, RangeInclusive, RangeTo};
+use core::ops::{Bound, Range, RangeFrom, RangeFull, RangeInclusive, RangeTo, RangeToInclusive};
 
 // Test the Range structs and syntax.
 
@@ -59,6 +59,12 @@ fn test_range_inclusive() {
     assert_eq!(r.next(), None);
 }
 
+#[test]
+fn test_range_to_inclusive() {
+    // Not much to test.
+    let _ = RangeToInclusive { end: 42 };
+}
+
 #[test]
 fn test_range_is_empty() {
     assert!(!(0.0..10.0).is_empty());
@@ -151,3 +157,43 @@ fn test_range_syntax_in_return_statement() {
     }
     // Not much to test.
 }
+
+#[test]
+fn range_structural_match() {
+    // test that all range types can be structurally matched upon
+
+    const RANGE: Range<usize> = 0..1000;
+    match RANGE {
+        RANGE => {}
+        _ => unreachable!(),
+    }
+
+    const RANGE_FROM: RangeFrom<usize> = 0..;
+    match RANGE_FROM {
+        RANGE_FROM => {}
+        _ => unreachable!(),
+    }
+
+    const RANGE_FULL: RangeFull = ..;
+    match RANGE_FULL {
+        RANGE_FULL => {}
+    }
+
+    const RANGE_INCLUSIVE: RangeInclusive<usize> = 0..=999;
+    match RANGE_INCLUSIVE {
+        RANGE_INCLUSIVE => {}
+        _ => unreachable!(),
+    }
+
+    const RANGE_TO: RangeTo<usize> = ..1000;
+    match RANGE_TO {
+        RANGE_TO => {}
+        _ => unreachable!(),
+    }
+
+    const RANGE_TO_INCLUSIVE: RangeToInclusive<usize> = ..=999;
+    match RANGE_TO_INCLUSIVE {
+        RANGE_TO_INCLUSIVE => {}
+        _ => unreachable!(),
+    }
+}