rename & add test

Author: mydea

packages/browser/src/sdk.ts

@@ -51,7 +51,8 @@ export function getDefaultIntegrations(options: Options): Integration[] {
   return integrations;
 }
 
-function applyDefaultOptions(optionsArg: BrowserOptions = {}): BrowserOptions {
+/** Exported only for tests. */
+export function applyDefaultOptions(optionsArg: BrowserOptions = {}): BrowserOptions {
   const defaultOptions: BrowserOptions = {
     defaultIntegrations: getDefaultIntegrations(optionsArg),
     release:
@@ -66,15 +67,15 @@ function applyDefaultOptions(optionsArg: BrowserOptions = {}): BrowserOptions {
 
   return {
     ...defaultOptions,
-    ...dropUndefinedKeysFlat(optionsArg),
+    ...dropTopLevelUndefinedKeys(optionsArg),
   };
 }
 
 /**
  * In contrast to the regular `dropUndefinedKeys` method,
  * this one does not deep-drop keys, but only on the top level.
  */
-function dropUndefinedKeysFlat<T extends object>(obj: T): Partial<T> {
+function dropTopLevelUndefinedKeys<T extends object>(obj: T): Partial<T> {
   const mutatetedObj: Partial<T> = {};
 
   for (const k of Object.getOwnPropertyNames(obj)) {

packages/browser/test/sdk.test.ts

@@ -13,7 +13,7 @@ import type { Client, Integration } from '@sentry/core';
 
 import type { BrowserOptions } from '../src';
 import { WINDOW } from '../src';
-import { init } from '../src/sdk';
+import { applyDefaultOptions, getDefaultIntegrations, init } from '../src/sdk';
 
 const PUBLIC_DSN = 'https://username@domain/123';
 
@@ -277,3 +277,100 @@ describe('init', () => {
     expect(client).not.toBeUndefined();
   });
 });
+
+describe('applyDefaultOptions', () => {
+  test('it works with empty options', () => {
+    const options = {};
+    const actual = applyDefaultOptions(options);
+
+    expect(actual).toEqual({
+      defaultIntegrations: expect.any(Array),
+      release: undefined,
+      autoSessionTracking: true,
+      sendClientReports: true,
+    });
+
+    expect(actual.defaultIntegrations && actual.defaultIntegrations.map(i => i.name)).toEqual(
+      getDefaultIntegrations(options).map(i => i.name),
+    );
+  });
+
+  test('it works with options', () => {
+    const options = {
+      tracesSampleRate: 0.5,
+      release: '1.0.0',
+      autoSessionTracking: false,
+    };
+    const actual = applyDefaultOptions(options);
+
+    expect(actual).toEqual({
+      defaultIntegrations: expect.any(Array),
+      release: '1.0.0',
+      autoSessionTracking: false,
+      sendClientReports: true,
+      tracesSampleRate: 0.5,
+    });
+
+    expect(actual.defaultIntegrations && actual.defaultIntegrations.map(i => i.name)).toEqual(
+      getDefaultIntegrations(options).map(i => i.name),
+    );
+  });
+
+  test('it works with defaultIntegrations=false', () => {
+    const options = {
+      defaultIntegrations: false,
+    } as const;
+    const actual = applyDefaultOptions(options);
+
+    expect(actual.defaultIntegrations).toStrictEqual(false);
+  });
+
+  test('it works with defaultIntegrations=[]', () => {
+    const options = {
+      defaultIntegrations: [],
+    };
+    const actual = applyDefaultOptions(options);
+
+    expect(actual.defaultIntegrations).toEqual([]);
+  });
+
+  test('it works with tracesSampleRate=undefined', () => {
+    const options = {
+      tracesSampleRate: undefined,
+    } as const;
+    const actual = applyDefaultOptions(options);
+
+    // Not defined, not even undefined
+    expect('tracesSampleRate' in actual).toBe(false);
+  });
+
+  test('it works with tracesSampleRate=null', () => {
+    const options = {
+      tracesSampleRate: null,
+    } as any;
+    const actual = applyDefaultOptions(options);
+
+    expect(actual.tracesSampleRate).toStrictEqual(null);
+  });
+
+  test('it works with tracesSampleRate=0', () => {
+    const options = {
+      tracesSampleRate: 0,
+    } as const;
+    const actual = applyDefaultOptions(options);
+
+    expect(actual.tracesSampleRate).toStrictEqual(0);
+  });
+
+  test('it does not deep-drop undefined keys', () => {
+    const options = {
+      obj: {
+        prop: undefined,
+      },
+    } as any;
+    const actual = applyDefaultOptions(options) as any;
+
+    expect('prop' in actual.obj).toBe(true);
+    expect(actual.obj.prop).toStrictEqual(undefined);
+  });
+});