diff --git a/src/analysis.zig b/src/analysis.zig
index ba53a93..f290cec 100644
--- a/src/analysis.zig
+++ b/src/analysis.zig
@@ -399,11 +399,20 @@ pub fn resolveTypeOfNode(analysis_ctx: *AnalysisContext, node: *ast.Node) ?*ast.
         },
         .Call => {
             const call = node.cast(ast.Node.Call).?;
+            const previous_tree = analysis_ctx.tree();
+
             const decl = resolveTypeOfNode(analysis_ctx, call.lhs) orelse return null;
             if (decl.cast(ast.Node.FnProto)) |fn_decl| {
+                if (previous_tree != analysis_ctx.tree()) {
+                    return resolveReturnType(analysis_ctx, fn_decl);
+                }
+
                 // Add type param values to the scope nodes
                 const param_len = std.math.min(call.params_len, fn_decl.params_len);
+                var scope_nodes = std.ArrayList(*ast.Node).fromOwnedSlice(&analysis_ctx.arena.allocator, analysis_ctx.scope_nodes);
+                var analysis_ctx_clone = analysis_ctx.clone() catch return null;
                 for (fn_decl.paramsConst()) |decl_param, param_idx| {
+                    if (param_idx >= param_len) break;
                     if (decl_param.name_token == null) continue;
 
                     // @TODO
@@ -420,9 +429,10 @@ pub fn resolveTypeOfNode(analysis_ctx: *AnalysisContext, node: *ast.Node) ?*ast.
                     // TODO This may invalidate the analysis context so we copy it.
                     //      However, if the argument hits an import we just ignore it for now.
                     //      Once we return our own types instead of directly using nodes we can fix this.
-                    var analysis_ctx_clone = analysis_ctx.clone() catch return null;
+                    std.debug.warn("Arg {} of fn {}\n", .{param_idx, analysis_ctx.tree().tokenSlice(fn_decl.name_token.?)});
                     const call_param_type = resolveTypeOfNode(&analysis_ctx_clone, call.paramsConst()[param_idx]) orelse continue;
                     if (analysis_ctx_clone.handle != analysis_ctx.handle) {
+                        analysis_ctx_clone = analysis_ctx.clone() catch return null;
                         continue;
                     }
 
@@ -444,7 +454,6 @@ pub fn resolveTypeOfNode(analysis_ctx: *AnalysisContext, node: *ast.Node) ?*ast.
                         .semicolon_token = decl_param.name_token.?,
                     };
 
-                    var scope_nodes = std.ArrayList(*ast.Node).fromOwnedSlice(&analysis_ctx.arena.allocator, analysis_ctx.scope_nodes);
                     scope_nodes.append(&var_decl_node.base) catch return null;
                     analysis_ctx.scope_nodes = scope_nodes.items;
                 }
diff --git a/src/main.zig b/src/main.zig
index 48a23c8..f986dcb 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -25,7 +25,7 @@ const ClientCapabilities = struct {
 var client_capabilities = ClientCapabilities{};
 
 const initialize_response =
-    \\,"result":{"capabilities":{"signatureHelpProvider":{"triggerCharacters":["(",","]},"textDocumentSync":1,"completionProvider":{"resolveProvider":false,"triggerCharacters":[".",":","@"]},"documentHighlightProvider":false,"hoverProvider":true,"codeActionProvider":false,"declarationProvider":true,"definitionProvider":true,"typeDefinitionProvider":true,"implementationProvider":false,"referencesProvider":false,"documentSymbolProvider":true,"colorProvider":false,"documentFormattingProvider":false,"documentRangeFormattingProvider":false,"foldingRangeProvider":false,"selectionRangeProvider":false,"workspaceSymbolProvider":false,"workspace":{"workspaceFolders":{"supported":true,"changeNotifications":true}}}}}
+    \\,"result":{"capabilities":{"signatureHelpProvider":{"triggerCharacters":["(",","]},"textDocumentSync":1,"completionProvider":{"resolveProvider":false,"triggerCharacters":[".",":","@"]},"documentHighlightProvider":false,"hoverProvider":true,"codeActionProvider":false,"declarationProvider":true,"definitionProvider":true,"typeDefinitionProvider":true,"implementationProvider":false,"referencesProvider":false,"documentSymbolProvider":true,"colorProvider":false,"documentFormattingProvider":false,"documentRangeFormattingProvider":false,"foldingRangeProvider":false,"selectionRangeProvider":false,"workspaceSymbolProvider":false,"semanticTokensProvider":{"legend":{"tokenTypes":["type","struct","enum","parameter","variable","enumMember","function","member","keyword","modifier","comment","string","number","operator"],"tokenModifiers":["definition","async","documentation"]},"rangeProvider":false,"documentProvider":true},"workspace":{"workspaceFolders":{"supported":true,"changeNotifications":true}}}}}
 ;
 
 const not_implemented_response =
@@ -744,6 +744,11 @@ fn processJsonRpc(parser: *std.json.Parser, json: []const u8, config: Config) !v
 
         document_store.closeDocument(uri);
     }
+    // Semantic highlighting
+    else if (std.mem.eql(u8, method, "textDocument/semanticTokens")) {
+        // @TODO Implement this (we dont get here from vscode atm even when we get the client capab.)
+        return try respondGeneric(id, empty_array_response);
+    }
     // Autocomplete / Signatures
     else if (std.mem.eql(u8, method, "textDocument/completion")) {
         const text_document = params.getValue("textDocument").?.Object;