fix(setGlobalConfig): merge multiple levels deep

Merges config multiple levels deep. Also fixes docs and tests.

docs/other/setGlobalConfig.md

@@ -1,6 +1,6 @@
 # setGlobalConfig
 
-This util function sets global config options, merging (1 level deep only) with the defaults. These options are then the defaults used for every request. It is the **recommended** way of setting global config. Setting global config directly is not recommended.
+This util function sets global config options, merging with the defaults. These options are then the defaults used for every request. It is the **recommended** way of setting global config. Setting global config directly is not recommended.
 
 ## Usage:
 
@@ -16,14 +16,16 @@ yahooFinance.setGlobalConfig({
 
 Notes:
 
-- Options are merged only one level deep:
+- Config provided to this function is validated.
+
+- Options are merged infinite levels deep:
 ```js
 import yahooFinance from 'yahoo-finance2';
 
 yahooFinance.setGlobalConfig({
     queue: {
         concurrency: 2,
-        // timeout not set anymore, may/will cause errors
+        // timeout is still set
     }
 });
 ```

src/lib/setGlobalConfig.spec.ts

@@ -1,11 +1,30 @@
 import testYf from "../../tests/testYf";
+import options from "./options";
 import setGlobalConfig from "./setGlobalConfig";
 const yf = testYf({ setGlobalConfig });
 
 describe("setGlobalConfig", () => {
-  it("sets config options", () => {
+  const optionsBackup = JSON.parse(JSON.stringify(options));
+  beforeEach(() => {
+    yf._opts = JSON.parse(JSON.stringify(optionsBackup));
+  });
+
+  it("sets config options and passes validation", () => {
     const configOverrides = { queue: { concurrency: 10, timeout: 90 } };
     yf.setGlobalConfig(configOverrides);
-    expect(yf._opts.queue).toEqual(configOverrides.queue);
+    expect(yf._opts).toEqual({ ...optionsBackup, ...configOverrides });
+  });
+  it("sets config options multiple levels deep", () => {
+    const configOverrides = { queue: { concurrency: 10 } };
+    yf.setGlobalConfig(configOverrides);
+    expect(yf._opts.queue).toEqual({
+      concurrency: 10,
+      timeout: optionsBackup.queue.timeout,
+    });
+  });
+  it("should throw on invalid config", () => {
+    expect(() => yf.setGlobalConfig({ queue: { abc: "" } })).toThrow(
+      /yahooFinance.setGlobalConfig called with invalid options\./
+    );
   });
 });

src/lib/setGlobalConfig.ts

@@ -13,7 +13,24 @@ export default function setGlobalConfig(
     options: this._opts.validation,
     schemaKey: "#/definitions/PartialOptions",
   });
-  for (const key of Reflect.ownKeys(config)) {
-    this._opts[key] = config[key as keyof Options];
+  mergeObjects(this._opts, config as Obj);
+}
+
+type Obj = Record<string, string | ObjRecurse>;
+
+// This is fine, since this is just a hack for recursive types
+// eslint-disable-next-line @typescript-eslint/no-empty-interface
+interface ObjRecurse extends Obj {}
+
+function mergeObjects(original: Obj, objToMerge: Obj) {
+  const ownKeys: (keyof typeof objToMerge)[] = Reflect.ownKeys(
+    objToMerge
+  ) as string[];
+  for (const key of ownKeys) {
+    if (typeof objToMerge[key] === "object") {
+      mergeObjects(original[key] as Obj, objToMerge[key] as Obj);
+    } else {
+      original[key] = objToMerge[key];
+    }
   }
 }