diff --git a/clang-tools-extra/clangd/index/Background.cpp b/clang-tools-extra/clangd/index/Background.cpp
--- a/clang-tools-extra/clangd/index/Background.cpp
+++ b/clang-tools-extra/clangd/index/Background.cpp
@@ -243,7 +243,7 @@
       // this thread sees the older version but finishes later. This should be
       // rare in practice.
       IndexedSymbols.update(
-          Path, std::make_unique<SymbolSlab>(std::move(*IF->Symbols)),
+          Uri, std::make_unique<SymbolSlab>(std::move(*IF->Symbols)),
           std::make_unique<RefSlab>(std::move(*IF->Refs)),
           std::make_unique<RelationSlab>(std::move(*IF->Relations)),
           Path == MainFile);
@@ -390,8 +390,9 @@
       SV.HadErrors = LS.HadErrors;
       ++LoadedShards;
 
-      IndexedSymbols.update(LS.AbsolutePath, std::move(SS), std::move(RS),
-                            std::move(RelS), LS.CountReferences);
+      IndexedSymbols.update(URI::create(LS.AbsolutePath).toString(),
+                            std::move(SS), std::move(RS), std::move(RelS),
+                            LS.CountReferences);
     }
   }
   Rebuilder.loadedShard(LoadedShards);
diff --git a/clang-tools-extra/clangd/index/FileIndex.cpp b/clang-tools-extra/clangd/index/FileIndex.cpp
--- a/clang-tools-extra/clangd/index/FileIndex.cpp
+++ b/clang-tools-extra/clangd/index/FileIndex.cpp
@@ -463,7 +463,8 @@
 void FileIndex::updateMain(PathRef Path, ParsedAST &AST) {
   auto Contents = indexMainDecls(AST);
   MainFileSymbols.update(
-      Path, std::make_unique<SymbolSlab>(std::move(std::get<0>(Contents))),
+      URI::create(Path).toString(),
+      std::make_unique<SymbolSlab>(std::move(std::get<0>(Contents))),
       std::make_unique<RefSlab>(std::move(std::get<1>(Contents))),
       std::make_unique<RelationSlab>(std::move(std::get<2>(Contents))),
       /*CountReferences=*/true);
diff --git a/clang-tools-extra/clangd/index/MemIndex.cpp b/clang-tools-extra/clangd/index/MemIndex.cpp
--- a/clang-tools-extra/clangd/index/MemIndex.cpp
+++ b/clang-tools-extra/clangd/index/MemIndex.cpp
@@ -112,14 +112,7 @@
 llvm::unique_function<IndexContents(llvm::StringRef) const>
 MemIndex::indexedFiles() const {
   return [this](llvm::StringRef FileURI) {
-    if (Files.empty())
-      return IndexContents::None;
-    auto Path = URI::resolve(FileURI, Files.begin()->first());
-    if (!Path) {
-      vlog("Failed to resolve the URI {0} : {1}", FileURI, Path.takeError());
-      return IndexContents::None;
-    }
-    return Files.contains(*Path) ? IdxContents : IndexContents::None;
+    return Files.contains(FileURI) ? IdxContents : IndexContents::None;
   };
 }
 
diff --git a/clang-tools-extra/clangd/index/dex/Dex.cpp b/clang-tools-extra/clangd/index/dex/Dex.cpp
--- a/clang-tools-extra/clangd/index/dex/Dex.cpp
+++ b/clang-tools-extra/clangd/index/dex/Dex.cpp
@@ -316,14 +316,7 @@
 llvm::unique_function<IndexContents(llvm::StringRef) const>
 Dex::indexedFiles() const {
   return [this](llvm::StringRef FileURI) {
-    if (Files.empty())
-      return IndexContents::None;
-    auto Path = URI::resolve(FileURI, Files.begin()->first());
-    if (!Path) {
-      vlog("Failed to resolve the URI {0} : {1}", FileURI, Path.takeError());
-      return IndexContents::None;
-    }
-    return Files.contains(*Path) ? IdxContents : IndexContents::None;
+    return Files.contains(FileURI) ? IdxContents : IndexContents::None;
   };
 }
 
diff --git a/clang-tools-extra/clangd/test/memory_tree.test b/clang-tools-extra/clangd/test/memory_tree.test
--- a/clang-tools-extra/clangd/test/memory_tree.test
+++ b/clang-tools-extra/clangd/test/memory_tree.test
@@ -23,7 +23,9 @@
 # CHECK-NEXT:             "_total": {{[0-9]+}}
 # CHECK-NEXT:           },
 # CHECK-NEXT:           "slabs": {
-# CHECK-NEXT:             "{{.*}}main.cpp": {
+# CHECK-NEXT:             "_self": {{[0-9]+}},
+# CHECK-NEXT:             "_total": {{[0-9]+}},
+# CHECK-NEXT:             "test:///main.cpp": {
 # CHECK-NEXT:               "_self": {{[0-9]+}},
 # CHECK-NEXT:               "_total": {{[0-9]+}},
 # CHECK-NEXT:               "references": {
@@ -38,9 +40,7 @@
 # CHECK-NEXT:                 "_self": {{[0-9]+}},
 # CHECK-NEXT:                 "_total": {{[0-9]+}}
 # CHECK-NEXT:               }
-# CHECK-NEXT:             },
-# CHECK-NEXT:             "_self": {{[0-9]+}},
-# CHECK-NEXT:             "_total": {{[0-9]+}}
+# CHECK-NEXT:             }
 # CHECK-NEXT:           }
 # CHECK-NEXT:         },
 # CHECK-NEXT:         "preamble": {
diff --git a/clang-tools-extra/clangd/unittests/DexTests.cpp b/clang-tools-extra/clangd/unittests/DexTests.cpp
--- a/clang-tools-extra/clangd/unittests/DexTests.cpp
+++ b/clang-tools-extra/clangd/unittests/DexTests.cpp
@@ -737,7 +737,7 @@
   RefSlab Refs;
   auto Size = Symbols.bytes() + Refs.bytes();
   auto Data = std::make_pair(std::move(Symbols), std::move(Refs));
-  llvm::StringSet<> Files = {testPath("foo.cc"), testPath("bar.cc")};
+  llvm::StringSet<> Files = {"unittest:///foo.cc", "unittest:///bar.cc"};
   Dex I(std::move(Data.first), std::move(Data.second), RelationSlab(),
         std::move(Files), IndexContents::All, std::move(Data), Size);
   auto ContainsFile = I.indexedFiles();
diff --git a/clang-tools-extra/clangd/unittests/FileIndexTests.cpp b/clang-tools-extra/clangd/unittests/FileIndexTests.cpp
--- a/clang-tools-extra/clangd/unittests/FileIndexTests.cpp
+++ b/clang-tools-extra/clangd/unittests/FileIndexTests.cpp
@@ -352,14 +352,14 @@
   Test.Code = std::string(MainCode.code());
   Test.Filename = "test.cc";
   auto AST = Test.build();
-  Index.updateMain(Test.Filename, AST);
+  Index.updateMain(testPath(Test.Filename), AST);
   // Add test2.cc
   TestTU Test2;
   Test2.HeaderCode = HeaderCode;
   Test2.Code = std::string(MainCode.code());
   Test2.Filename = "test2.cc";
   AST = Test2.build();
-  Index.updateMain(Test2.Filename, AST);
+  Index.updateMain(testPath(Test2.Filename), AST);
 
   EXPECT_THAT(getRefs(Index, Foo.ID),
               RefsAre({AllOf(RefRange(MainCode.range("foo")),
@@ -387,7 +387,7 @@
   Test.Code = std::string(MainCode.code());
   Test.Filename = "test.cc";
   auto AST = Test.build();
-  Index.updateMain(Test.Filename, AST);
+  Index.updateMain(testPath(Test.Filename), AST);
 
   auto HeaderMacro = findSymbol(Test.headerSymbols(), "HEADER_MACRO");
   EXPECT_THAT(getRefs(Index, HeaderMacro.ID),
diff --git a/clang-tools-extra/clangd/unittests/IndexTests.cpp b/clang-tools-extra/clangd/unittests/IndexTests.cpp
--- a/clang-tools-extra/clangd/unittests/IndexTests.cpp
+++ b/clang-tools-extra/clangd/unittests/IndexTests.cpp
@@ -229,7 +229,7 @@
   RefSlab Refs;
   auto Size = Symbols.bytes() + Refs.bytes();
   auto Data = std::make_pair(std::move(Symbols), std::move(Refs));
-  llvm::StringSet<> Files = {testPath("foo.cc"), testPath("bar.cc")};
+  llvm::StringSet<> Files = {"unittest:///foo.cc", "unittest:///bar.cc"};
   MemIndex I(std::move(Data.first), std::move(Data.second), RelationSlab(),
              std::move(Files), IndexContents::All, std::move(Data), Size);
   auto ContainsFile = I.indexedFiles();
@@ -506,7 +506,7 @@
   RefSlab DynRefs;
   auto DynSize = DynSymbols.bytes() + DynRefs.bytes();
   auto DynData = std::make_pair(std::move(DynSymbols), std::move(DynRefs));
-  llvm::StringSet<> DynFiles = {testPath("foo.cc")};
+  llvm::StringSet<> DynFiles = {"unittest:///foo.cc"};
   MemIndex DynIndex(std::move(DynData.first), std::move(DynData.second),
                     RelationSlab(), std::move(DynFiles), IndexContents::Symbols,
                     std::move(DynData), DynSize);
@@ -514,7 +514,7 @@
   RefSlab StaticRefs;
   auto StaticData =
       std::make_pair(std::move(StaticSymbols), std::move(StaticRefs));
-  llvm::StringSet<> StaticFiles = {testPath("foo.cc"), testPath("bar.cc")};
+  llvm::StringSet<> StaticFiles = {"unittest:///foo.cc", "unittest:///bar.cc"};
   MemIndex StaticIndex(
       std::move(StaticData.first), std::move(StaticData.second), RelationSlab(),
       std::move(StaticFiles), IndexContents::References, std::move(StaticData),