introduce indirection to be able to mock UrlFetchApp methods

src-test/callFunctionInTest.ts

@@ -12,7 +12,7 @@ export function callFunctionInTest(functionName: string, testName: string, ...pa
     console.log(`calling ${functionName} in test "${testName}"`);
 
     // there is no global object (like window) in apps script, so this is how we get a global function by name
-    const fn = eval(functionName);
+    const fn = (new Function(`return ${functionName};`))();
     const result = fn(...params);
     return JSON.stringify(result);
   } catch (e) {
@@ -29,7 +29,7 @@ export function callFunctionInTestWithMockFixture(
   const fixtureInstance = (ALL_FIXTURES[fixture.name])(...params);
   console.log(fixture.name);
   console.log(ALL_FIXTURES[fixture.name].toString());
-  console.log(UrlFetchApp.fetchAll.toString());
+  console.log((new Function('return getServices;'))()().UrlFetchApp.fetchAll);
   fixtureInstance.setUp();
   try {
     return callFunctionInTest(functionName, testName, ...params);

src-test/mock-fixtures/urlfetchapp-mock.ts

@@ -6,27 +6,37 @@
  */
 
 export default function urlFetchAppMock(errorToThrow: string, throwAsString: boolean = false) {
-  const previousFetchAll = UrlFetchApp.fetchAll;
   let isThrown = false;
 
-  return {
-    setUp() {
-      UrlFetchApp.fetchAll = function (...args) {
-        if (!isThrown) {
-          isThrown = true;
+  const mockUrlFetchApp = new Proxy(UrlFetchApp, {
+    get(target, prop) {
+      if (prop === 'fetchAll') {
+        return function (...args) {
+          if (!isThrown) {
+            isThrown = true;
 
-          if (throwAsString) {
-            throw errorToThrow;
+            if (throwAsString) {
+              throw errorToThrow;
+            } else {
+              throw new Error(errorToThrow);
+            }
           } else {
-            throw new Error(errorToThrow);
+            return target[prop].call(this, ...args);
           }
-        } else {
-          return previousFetchAll.call(this, ...args);
-        }
-      };
+        };
+      }
+      return target[prop];
+    }
+  });
+
+  return {
+    setUp() {
+      const getServices = (new Function('return getServices;'))();
+      getServices().UrlFetchApp = mockUrlFetchApp;
     },
     tearDown() {
-      UrlFetchApp.fetchAll = previousFetchAll;
+      const getServices = (new Function('return getServices;'))();
+      getServices().UrlFetchApp = UrlFetchApp;
     },
   };
 }

src/api.ts

@@ -10,6 +10,7 @@ import { getScriptElapsedTime } from './connector';
 import { throwUnexpectedError, throwUserError } from './error';
 import URLFetchRequest = GoogleAppsScript.URL_Fetch.URLFetchRequest;
 import { debugLog, log, logError } from './log';
+import { getServices } from './services';
 
 const SCRIPT_RUNTIME_LIMIT = parseInt(env.SCRIPT_RUNTIME_LIMIT) || 0;
 const API_REQUEST_RETRY_LIMIT_IN_SECS = parseInt(env.API_REQUEST_RETRY_LIMIT_IN_SECS) || 0;
@@ -212,7 +213,7 @@ export function fetchAll(requests: MatomoRequestParams[], options: ApiFetchOptio
 
     let responses = [];
     try {
-      responses = UrlFetchApp.fetchAll(urlsToFetch);
+      responses = getServices().UrlFetchApp.fetchAll(urlsToFetch);
     } catch (e) {
       const errorMessage = e.message || e;
 

src/index.ts

@@ -9,3 +9,4 @@ export { extractBasicAuthFromUrl, fetchAll, isApiErrorNonRandom } from './api';
 export * from './auth';
 export * from './config';
 export * from './data';
+export * from './services';

src/services.ts

@@ -0,0 +1,14 @@
+/**
+ * Matomo - free/libre analytics platform
+ *
+ * @link https://matomo.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ */
+
+const SERVICES = {
+  UrlFetchApp,
+};
+
+export function getServices() {
+  return SERVICES;
+}