[clangd] Support configuration of inlay hints.maain

The idea is that the feature will always be advertised at the LSP level, but
depending on config we'll return partial or no responses.

We try to avoid doing the analysis for hints we're not going to return.

Examples of syntax:
```
InlayHints:
  Enabled: No
---
InlayHints:
  ParameterNames: No
---
InlayHints:
  ParameterNames: Yes
  DeducedTypes: Yes
```

Differential Revision: https://reviews.llvm.org/D116713

1 files changed, 12 insertions, 0 deletions

diff --git a/clang-tools-extra/clangd/ConfigFragment.h b/clang-tools-extra/clangd/ConfigFragment.h
index 31c4636efa0b..d165b6305aa5 100644
--- a/clang-tools-extra/clangd/ConfigFragment.h
+++ b/clang-tools-extra/clangd/ConfigFragment.h
@@ -283,6 +283,18 @@ struct Fragment {
     llvm::Optional<Located<bool>> ShowAKA;
   };
   HoverBlock Hover;
+
+  /// Configures labels shown inline with the code.
+  struct InlayHintsBlock {
+    /// Enables/disables the inlay-hints feature.
+    llvm::Optional<Located<bool>> Enabled;
+
+    /// Show parameter names before function arguments.
+    llvm::Optional<Located<bool>> ParameterNames;
+    /// Show deduced types for `auto`.
+    llvm::Optional<Located<bool>> DeducedTypes;
+  };
+  InlayHintsBlock InlayHints;
 };
 
 } // namespace config