[llvm] [llvm][ADT] Use ADL to find begin()/end() in interleave* (PR #87669)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,38 @@
+//===- unittests/ADT/Interleave.cpp - Interleave unit tests ---------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+TEST(InterleaveTest, Interleave) {
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MaskRay wrote:

Surround `TEST` with `namespace { ... }`

https://github.com/llvm/llvm-project/pull/87669