[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 +449,39 @@ TEST(RemoteMarshallingTest, URIToRelativePathTranslation) {
   llvm::consumeError(RelativePath.takeError());
 }
 
+TEST(RemoteMarshallingTest, CrossPlatformPathsRoundTrip) {
+  llvm::BumpPtrAllocator Arena;
+  llvm::UniqueStringSaver Strings(Arena);
+
+  // Simulate a Windows-built index
+  Marshaller ProtobufMarshaller("C:/remote/project/",
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bwiklak wrote:

You're right about first point but, looking at the code, URI::createFile won't work here. On a Unix host, it uses the native path style internally, so it doesn't recognize C:\\remote\\project\\ (or even C:/remote/project/) as having a Windows root. Specifically, in uriFromAbsolutePath which this function calls.

I wanted those test to still be cross-platform.



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