diagnostics for simple infoview

server/leanserver/GameServer/RpcHandlers.lean

@@ -147,4 +147,34 @@ builtin_initialize
     (Option PlainGoal)
     getGoals
 
+
+structure Diagnostic where
+  severity : Option Lean.Lsp.DiagnosticSeverity
+  message : String
+deriving FromJson, ToJson
+
+open RequestM in
+def getDiagnostics (params : GetInteractiveDiagnosticsParams) : RequestM (RequestTask (Array Diagnostic)) := do
+  let doc ← readDoc
+  let rangeEnd := params.lineRange?.map fun range =>
+    doc.meta.text.lspPosToUtf8Pos ⟨range.«end», 0⟩
+  let t := doc.cmdSnaps.waitAll fun snap => rangeEnd.all (snap.beginPos < ·)
+  pure <| t.map fun (snaps, _) =>
+    let diags? := snaps.getLast?.map fun snap =>
+      snap.interactiveDiags.toArray.filterMap fun diag =>
+        if params.lineRange?.all fun ⟨s, e⟩ =>
+          -- does [s,e) intersect [diag.fullRange.start.line,diag.fullRange.end.line)?
+          s ≤ diag.fullRange.start.line ∧ diag.fullRange.start.line < e ∨
+          diag.fullRange.start.line ≤ s ∧ s < diag.fullRange.end.line
+        then some {message := diag.message.stripTags, severity := diag.severity?}
+        else none
+    pure <| diags?.getD #[]
+
+builtin_initialize
+  registerBuiltinRpcProcedure
+    `Game.getDiagnostics
+    GetInteractiveDiagnosticsParams
+    (Array Diagnostic)
+    getDiagnostics
+
 end GameServer