Negative array indexing

2 files changed, 26 insertions, 6 deletions

diff --git a/tests/typ/code/array.typ b/tests/typ/code/array.typ
index df37dd45..cd163175 100644
--- a/tests/typ/code/array.typ
+++ b/tests/typ/code/array.typ
@@ -31,21 +31,33 @@
 
 ---
 // Test rvalue out of bounds.
+// Error: 2-14 array index out of bounds (index: 5, len: 3)
+{(1, 2, 3)(5)}
+
+---
+// Test lvalue out of bounds.
 {
   let array = (1, 2, 3)
-  // Error: 3-11 array index out of bounds (index: 5, len: 3)
-  array(5)
+  // Error: 3-11 array index out of bounds (index: 3, len: 3)
+  array(3) = 5
 }
 
 ---
-// Test lvalue out of bounds.
+// Test negative indices.
 {
-  let array = (1, 2, 3)
-  // Error: 3-12 array index out of bounds (index: -1, len: 3)
-  array(-1) = 5
+  let array = (1, 2, 3, 4)
+  test(array(0), 1)
+  test(array(-1), 4)
+  test(array(-2), 3)
+  test(array(-3), 2)
+  test(array(-4), 1)
 }
 
 ---
+// Error: 2-15 array index out of bounds (index: -4, len: 3)
+{(1, 2, 3)(-4)}
+
+---
 // Test non-collection indexing.
 
 {
diff --git a/tests/typ/utility/collection.typ b/tests/typ/utility/collection.typ
index 924200cb..3414f0a9 100644
--- a/tests/typ/utility/collection.typ
+++ b/tests/typ/utility/collection.typ
@@ -38,12 +38,20 @@
 #test((1, 2, 3, 4).slice(2), (3, 4))
 #test(range(10).slice(2, 6), (2, 3, 4, 5))
 #test(range(10).slice(4, count: 3), (4, 5, 6))
+#test((1, 2, 3).slice(2, -2), ())
+#test((1, 2, 3).slice(-2, 2), (2,))
+#test((1, 2, 3).slice(-3, 2), (1, 2))
+#test("ABCD".split("").slice(1, -1).join("-"), "A-B-C-D")
 
 ---
 // Error: 3-31 array index out of bounds (index: 12, len: 10)
 { range(10).slice(9, count: 3) }
 
 ---
+// Error: 3-25 array index out of bounds (index: -4, len: 3)
+{ (1, 2, 3).slice(0, -4) }
+
+---
 // Error: 2:17-2:19 missing argument: index
 #let numbers = ()
 { numbers.insert() }