[clang] Introduce paged vector (PR #66430)

[Shafik Yaghmour via cfe-commits]

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@@ -0,0 +1,84 @@
+//===- llvm/unittest/ADT/PagedVectorTest.cpp ------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// PagedVector unit tests.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/PagedVector.h"
+#include "gtest/gtest.h"
+
+namespace llvm {
+TEST(PagedVectorTest, FunctionalityTest) {
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shafik wrote:

I don't see tests for `clear()`, `empty()` or `at(..)` and I think we should have `EXPECT_DEATH` tests for assertions that are testable.

https://github.com/llvm/llvm-project/pull/66430