[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, 17 insertions, 0 deletions

diff --git a/clang-tools-extra/clangd/ConfigCompile.cpp b/clang-tools-extra/clangd/ConfigCompile.cpp
index 18afdeb3cb5c..a606b98a2dba 100644
--- a/clang-tools-extra/clangd/ConfigCompile.cpp
+++ b/clang-tools-extra/clangd/ConfigCompile.cpp
@@ -197,6 +197,7 @@ struct FragmentCompiler {
     compile(std::move(F.Diagnostics));
     compile(std::move(F.Completion));
     compile(std::move(F.Hover));
+    compile(std::move(F.InlayHints));
   }
 
   void compile(Fragment::IfBlock &&F) {
@@ -526,6 +527,22 @@ struct FragmentCompiler {
     }
   }
 
+  void compile(Fragment::InlayHintsBlock &&F) {
+    if (F.Enabled)
+      Out.Apply.push_back([Value(**F.Enabled)](const Params &, Config &C) {
+        C.InlayHints.Enabled = Value;
+      });
+    if (F.ParameterNames)
+      Out.Apply.push_back(
+          [Value(**F.ParameterNames)](const Params &, Config &C) {
+            C.InlayHints.Parameters = Value;
+          });
+    if (F.DeducedTypes)
+      Out.Apply.push_back([Value(**F.DeducedTypes)](const Params &, Config &C) {
+        C.InlayHints.DeducedTypes = Value;
+      });
+  }
+
   constexpr static llvm::SourceMgr::DiagKind Error = llvm::SourceMgr::DK_Error;
   constexpr static llvm::SourceMgr::DiagKind Warning =
       llvm::SourceMgr::DK_Warning;