[clang-tools-extra] Symbol tags in SymbolInformation, WorkspaceSymbol, CallHierarchyItem and TypeHierarchyItem (PR #170103)

[via cfe-commits]

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@@ -22,6 +23,15 @@ namespace clangd {
 
 LLVM_ENABLE_BITMASK_ENUMS_IN_NAMESPACE();
 
+/// A bitmask type representing symbol tags supported by LSP.
+/// \see
+/// https://microsoft.github.io/language-server-protocol/specifications/specification-current/#symbolTag
+using SymbolTags = uint32_t;
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timon-ul wrote:

I think we can couple this more deeply to `SymbolTag`, making the below assert also obsolete in the process. For this I see 2 ways to go about this, the first one is we simply operate like `SymbolFlag` (further down in this file), where we directly operate on the enum, making it already represent a combination of enums. Also I like that we have pre defined operators on the enum there. I can understand if you like to have a more clear difference between the enum and the aggregated enum, so the second option would be to simply set `using SymbolTags = SymbolTag` to guarantee the same underlaying type. By the way both of these options want you to then have a enum for `0`, but since you start assigning values with `1` you can easily add a `None` enum with value `0` (again I am referencing `SymbolFlag`) without it costing additional encoding space.

https://github.com/llvm/llvm-project/pull/170103