From 4cb608e92143b00c46eb5dd479a92ab6763a6a05 Mon Sep 17 00:00:00 2001
From: Hila Friedman <red.black.liquorice@gmail.com>
Date: Wed, 24 Jun 2026 13:42:58 +0300
Subject: [PATCH] add test coverage for overlapping assignment

---
 test/behavior.zig                    |  1 +
 test/behavior/overlapping_assign.zig | 37 ++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)
 create mode 100644 test/behavior/overlapping_assign.zig

diff --git a/test/behavior.zig b/test/behavior.zig
index 32be1951bcd7359632884683ca6b2108bd18a717..26333758086ae14904d9c275e4afcb55eb3176f7 100644
--- a/test/behavior.zig
+++ b/test/behavior.zig
@@ -60,6 +60,7 @@ test {
     _ = @import("behavior/nan.zig");
     _ = @import("behavior/null.zig");
     _ = @import("behavior/optional.zig");
+    _ = @import("behavior/overlapping_assign.zig");
     _ = @import("behavior/packed-struct.zig");
     _ = @import("behavior/packed_struct_explicit_backing_int.zig");
     _ = @import("behavior/packed-union.zig");
diff --git a/test/behavior/overlapping_assign.zig b/test/behavior/overlapping_assign.zig
new file mode 100644
index 0000000000000000000000000000000000000000..42e11b20fea2006f660c4ae818d3c16972e1f63c
--- /dev/null
+++ b/test/behavior/overlapping_assign.zig
@@ -0,0 +1,37 @@
+const std = @import("std");
+const expectEqualSlices = std.testing.expectEqualSlices;
+
+test "assignment to overlapping memory" {
+    try theTest();
+    try comptime theTest();
+}
+
+fn theTest() !void {
+    var a1: [3]usize = .{ 0, 1, 2 };
+    a1[1..3].* = a1[0..2].*;
+    try expectEqualSlices(usize, &.{ 0, 0, 1 }, &a1);
+
+    var a2: [3]usize = .{ 0, 1, 2 };
+    a2[0..2].* = a2[1..3].*;
+    try expectEqualSlices(usize, &.{ 1, 2, 2 }, &a2);
+
+    var a3: [16]u8 = .{
+        0, 1, 2,  3,  4,  5,  6,  7,
+        8, 9, 10, 11, 12, 13, 14, 15,
+    };
+    a3[1..16].* = a3[0..15].*;
+    try expectEqualSlices(u8, &.{
+        0, 0, 1, 2,  3,  4,  5,  6,
+        7, 8, 9, 10, 11, 12, 13, 14,
+    }, &a3);
+
+    var a4: [16]u8 = .{
+        0, 1, 2,  3,  4,  5,  6,  7,
+        8, 9, 10, 11, 12, 13, 14, 15,
+    };
+    a4[0..15].* = a4[1..16].*;
+    try expectEqualSlices(u8, &.{
+        1, 2,  3,  4,  5,  6,  7,  8,
+        9, 10, 11, 12, 13, 14, 15, 15,
+    }, &a4);
+}
-- 
2.54.0