[clang-tools-extra] Add clangd-index-server support for cross platform indexes (PR #207202)

[Bartosz Wiklak via cfe-commits]

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@@ -449,6 +449,44 @@ TEST(RemoteMarshallingTest, URIToRelativePathTranslation) {
   llvm::consumeError(RelativePath.takeError());
 }
 
+TEST(RemoteMarshallingTest, CrossPlatformPathsRoundTrip) {
+  llvm::BumpPtrAllocator Arena;
+  llvm::UniqueStringSaver Strings(Arena);
+
+  // Simulate a Windows-built index.
+  std::string RemoteIndexRoot = "C:\\remote\\project\\";
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bwiklak wrote:

fixed

https://github.com/llvm/llvm-project/pull/207202