From 1c7706b58cf964082568861327ea416a24381c47 Mon Sep 17 00:00:00 2001
From: Faizan <fai1ggj@gmail.com>
Date: Wed, 14 Oct 2026 14:47:45 +0530
Subject: [PATCH 1/2] feat(browser): add LoaderSentry type

---
 packages/browser/src/exports.ts        |  1 +
 packages/browser/src/loader.ts         | 27 +++++++++++++++++++++
 packages/browser/test/loader.test-d.ts | 33 ++++++++++++++++++++++++++
 3 files changed, 61 insertions(+)
 create mode 100644 packages/browser/src/loader.ts
 create mode 100644 packages/browser/test/loader.test-d.ts

diff --git a/packages/browser/src/exports.ts b/packages/browser/src/exports.ts
index 48b09d3c1acc..f7d96bb5f872 100644
--- a/packages/browser/src/exports.ts
+++ b/packages/browser/src/exports.ts
@@ -23,6 +23,7 @@ export type {
 } from '@sentry/core';
 
 export type { BrowserOptions } from './client';
+export type { LoaderSentry } from './loader';
 
 export {
   addEventProcessor,
diff --git a/packages/browser/src/loader.ts b/packages/browser/src/loader.ts
new file mode 100644
index 000000000000..654812b39d18
--- /dev/null
+++ b/packages/browser/src/loader.ts
@@ -0,0 +1,27 @@
+
+type LoaderApi = typeof import('@sentry/core') &
+  typeof import('./sdk') &
+  typeof import('./report-dialog');
+
+type VoidReturningFunction<T> = T extends (...args: infer Args) => unknown
+  ? (...args: Args) => void
+  : never;
+
+type LoaderQueuedMethod =
+  | 'init'
+  | 'addBreadcrumb'
+  | 'captureMessage'
+  | 'captureException'
+  | 'captureEvent'
+  | 'withScope'
+  | 'showReportDialog';
+
+/**
+ * The subset of the Sentry browser API supported by the CDN loader.
+ *
+ * Queued calls do not synchronously return the result of the underlying SDK
+ * method, so their return types are void.
+ */
+export type LoaderSentry = {
+  [Method in LoaderQueuedMethod]: VoidReturningFunction<LoaderApi[Method]>;
+} & Pick<LoaderApi, 'onLoad' | 'forceLoad'>;
diff --git a/packages/browser/test/loader.test-d.ts b/packages/browser/test/loader.test-d.ts
new file mode 100644
index 000000000000..c06eb393fa9b
--- /dev/null
+++ b/packages/browser/test/loader.test-d.ts
@@ -0,0 +1,33 @@
+import { expectTypeOf, it, describe } from 'vitest';
+import type { LoaderSentry } from '../src/loader';
+
+describe('LoaderSentry', () => {
+  it('exposes the APIs supported by the loader', () => {
+    expectTypeOf<LoaderSentry>().toHaveProperty('init');
+    expectTypeOf<LoaderSentry>().toHaveProperty('addBreadcrumb');
+    expectTypeOf<LoaderSentry>().toHaveProperty('captureMessage');
+    expectTypeOf<LoaderSentry>().toHaveProperty('captureException');
+    expectTypeOf<LoaderSentry>().toHaveProperty('captureEvent');
+    expectTypeOf<LoaderSentry>().toHaveProperty('withScope');
+    expectTypeOf<LoaderSentry>().toHaveProperty('showReportDialog');
+    expectTypeOf<LoaderSentry>().toHaveProperty('onLoad');
+    expectTypeOf<LoaderSentry>().toHaveProperty('forceLoad');
+  });
+
+  it('does not expose unsupported APIs', () => {
+    expectTypeOf<LoaderSentry>().not.toHaveProperty('addIntegration');
+    expectTypeOf<LoaderSentry>().not.toHaveProperty('captureFeedback');
+    expectTypeOf<LoaderSentry>().not.toHaveProperty('flush');
+    expectTypeOf<LoaderSentry>().not.toHaveProperty('close');
+  });
+
+  it('uses void return types for queued methods', () => {
+    expectTypeOf<LoaderSentry['init']>().returns.toBeVoid();
+    expectTypeOf<LoaderSentry['addBreadcrumb']>().returns.toBeVoid();
+    expectTypeOf<LoaderSentry['captureMessage']>().returns.toBeVoid();
+    expectTypeOf<LoaderSentry['captureException']>().returns.toBeVoid();
+    expectTypeOf<LoaderSentry['captureEvent']>().returns.toBeVoid();
+    expectTypeOf<LoaderSentry['withScope']>().returns.toBeVoid();
+    expectTypeOf<LoaderSentry['showReportDialog']>().returns.toBeVoid();
+  });
+});

From 5b2cfb0563239d8230d81b2208e8ded22ff1d4cb Mon Sep 17 00:00:00 2001
From: Faizan <fai1ggj@gmail.com>
Date: Wed, 14 Oct 2026 15:38:00 +0530
Subject: [PATCH 2/2] test(browser): enable loader type tests

---
 packages/browser/tsconfig.loader.test.json | 4 ++++
 packages/browser/vite.config.ts            | 6 ++++++
 2 files changed, 10 insertions(+)
 create mode 100644 packages/browser/tsconfig.loader.test.json

diff --git a/packages/browser/tsconfig.loader.test.json b/packages/browser/tsconfig.loader.test.json
new file mode 100644
index 000000000000..efe243dbdad2
--- /dev/null
+++ b/packages/browser/tsconfig.loader.test.json
@@ -0,0 +1,4 @@
+{
+  "extends": "./tsconfig.test.json",
+  "include": ["test/loader.test-d.ts"]
+}
diff --git a/packages/browser/vite.config.ts b/packages/browser/vite.config.ts
index 0869faa66b74..f29f65d0a6a3 100644
--- a/packages/browser/vite.config.ts
+++ b/packages/browser/vite.config.ts
@@ -1,3 +1,4 @@
+
 import { defineConfig } from 'vitest/config';
 import baseConfig from '../../vite/vite.config';
 
@@ -9,5 +10,10 @@ export default defineConfig({
     fakeTimers: {
       toFake: ['setTimeout', 'clearTimeout', 'setInterval', 'clearInterval', 'setImmediate', 'clearImmediate', 'Date'],
     },
+    typecheck: {
+      enabled: true,
+      include: ['test/loader.test-d.ts'],
+      tsconfig: './tsconfig.loader.test.json',
+    },
   },
 });