[clang-tools-extra] [clangd] Add background index path mapping (PR #180285)

[Aleksandr Platonov via cfe-commits]

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@@ -444,6 +444,176 @@ TEST(SerializationTest, NoCrashOnBadStringTableSize) {
               testing::HasSubstr("bytes is implausible"));
 }
 
+// Verify path remapping is applied to all URI fields during load/store.
+// An index is generated at /home/project. A second client at /workarea/project
+// loads and re-stores the shards. On-disk content always contains the
+// /home/project paths so the index remains portable.
+TEST(SerializationTest, PathTransformRoundTrip) {
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ArcsinX wrote:

I think that for serialization test we should not focus on paths, but on strings transformation. I.e. just check that path transformation is applied to each(?) string in strings table. I hope this can reduce the test size

https://github.com/llvm/llvm-project/pull/180285