[llvm] [CAS] Add OnDiskDataAllocator (PR #161264)

[Paul Kirth via llvm-commits]

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@@ -0,0 +1,55 @@
+//===----------------------------------------------------------------------===//
+//
+// 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/CAS/OnDiskDataAllocator.h"
+#include "llvm/CAS/MappedFileRegionArena.h"
+#include "llvm/Config/llvm-config.h"
+#include "llvm/Support/Alignment.h"
+#include "llvm/Testing/Support/Error.h"
+#include "llvm/Testing/Support/SupportHelpers.h"
+
+#if LLVM_ENABLE_ONDISK_CAS
+
+using namespace llvm;
+using namespace llvm::cas;
+
+TEST(OnDiskDataAllocatorTest, Allocate) {
+  unittest::TempDir Temp("data-allocator", /*Unique=*/true);
+  constexpr size_t MB = 1024u * 1024u;
+
+  std::optional<OnDiskDataAllocator> Allocator;
+  ASSERT_THAT_ERROR(OnDiskDataAllocator::create(
+                        Temp.path("allocator"), "data", /*MaxFileSize=*/MB,
+                        /*NewFileInitialSize=*/std::nullopt)
+                        .moveInto(Allocator),
+                    Succeeded());
+
+  // Allocate.
+  {
+    for (size_t Size = 1; Size < 16; ++Size) {
+      OnDiskDataAllocator::pointer P;
+      ASSERT_THAT_ERROR(Allocator->allocate(Size).moveInto(P), Succeeded());
+      ASSERT_TRUE(
+          isAligned(MappedFileRegionArena::getAlign(), P.getOffset().get()));
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ilovepi wrote:

Shouldn't this be `EXPECT_*`? I don't think you need to abort the test if this fails, do you? I'd guess the rest of them after this point are in the same boat?

https://github.com/llvm/llvm-project/pull/161264