[llvm] [llvm/CAS] Improve layering and decouple `UnifiedOnDiskCache` from the builtin hash implementation (PR #177280)

[Nico Weber via llvm-commits]

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@@ -44,6 +81,31 @@ static CASTestingEnv createOnDisk(int I) {
   return CASTestingEnv{std::move(CAS), std::move(Cache), std::move(Temp)};
 }
 INSTANTIATE_TEST_SUITE_P(OnDiskCAS, CASTest, ::testing::Values(createOnDisk));
+
+static void builtinDigest(ArrayRef<ArrayRef<uint8_t>> Refs, ArrayRef<char> Data,
+                          SmallVectorImpl<uint8_t> &Result) {
+  llvm::unittest::cas::HashType Digest =
+      llvm::unittest::cas::digest(toStringRef(Data), Refs);
+  Result.assign(Digest.begin(), Digest.end());
+}
+
+INSTANTIATE_TEST_SUITE_P(Builtin, CustomHasherOnDiskCASTest,
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nico wrote:

Oh, here it is, apologies! I expected it in the same file.

https://github.com/llvm/llvm-project/pull/177280