Fix a bunch of auto-complete issues

actions-languageservice/src/expression-validation/functions.ts

@@ -0,0 +1,13 @@
+import {data, wellKnownFunctions} from "@github/actions-expressions";
+
+// Custom implementations for standard actions-expression functions used during validation and auto-completion.
+// For example, for fromJson we'll most likely not have a valid input. In order to not throw, we'll always
+// return an empty dictionary.
+export const validatorFunctions = new Map(
+  Object.entries({
+    fromjson: {
+      ...wellKnownFunctions.fromjson,
+      call: () => new data.Dictionary()
+    }
+  })
+);