chore: Update and fix config type test

lib/config/builder/config-types.test.ts

@@ -0,0 +1,25 @@
+import {
+  ListValueSpecOf,
+  ValueSpecList,
+  isValueSpecListOf,
+} from "../config-types";
+import { Config } from "./config";
+import { List } from "./list";
+import { Value } from "./value";
+
+describe("Config Types", () => {
+  test("isValueSpecListOf", () => {
+    const options = [List.obj, List.string, List.number];
+    for (const option of options) {
+      const test = option({} as any, { spec: Config.of({}) } as any) as any;
+      const someList = Value.list(test).build();
+      if (isValueSpecListOf(someList, "string")) {
+        someList.spec satisfies ListValueSpecOf<"string">;
+      } else if (isValueSpecListOf(someList, "number")) {
+        someList.spec satisfies ListValueSpecOf<"number">;
+      } else if (isValueSpecListOf(someList, "object")) {
+        someList.spec satisfies ListValueSpecOf<"object">;
+      }
+    }
+  });
+});

lib/config/config-types.ts

@@ -129,9 +129,9 @@ export interface ValueSpecListOf<T extends ListValueSpecType>
 
 // sometimes the type checker needs just a little bit of help
 export function isValueSpecListOf<S extends ListValueSpecType>(
-  t: ValueSpecList,
+  t: ValueSpecListOf<ListValueSpecType>,
   s: S
-): t is ValueSpecListOf<S> {
+): t is ValueSpecListOf<S> & { spec: ListValueSpecOf<S> } {
   return t.spec.type === s;
 }