fix(nitro): Handle non-boolean sourcemap values ('hidden', 'inline')

Nitro types `sourcemap` as `boolean`, but the value is forwarded to Vite
which also accepts `'hidden'` and `'inline'`. The previous logic treated
any non-`true`/`false` value as unset and overwrote it with `'hidden'`
plus default deletion, which (1) clobbered an explicit `'inline'` choice
and (2) auto-deleted `.map` files the user had configured via `'hidden'`.

Now we keep `'hidden'` and `true` as-is (upload, no deletion), warn and
skip upload for `'inline'` (no `.map` files exist to upload), and only
enable hidden + deletion when `sourcemap` is unset.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: logaretm

packages/nitro/src/sourceMaps.ts

@@ -26,6 +26,7 @@ function shouldSkipSourcemapUpload(nitro: Nitro, options?: SentryNitroOptions):
     nitro.options.dev ||
     nitro.options.preset === 'nitro-prerender' ||
     nitro.options.sourcemap === false ||
+    (nitro.options.sourcemap as unknown) === 'inline' ||
     options?.sourcemaps?.disable === true
   );
 }
@@ -141,23 +142,35 @@ export function configureSourcemapSettings(
     return { sentryEnabledSourcemaps: false };
   }
 
-  if (config.sourcemap === false) {
+  // Nitro types `sourcemap` as `boolean`, but it forwards the value to Vite which also accepts `'hidden'` and `'inline'`.
+  const userSourcemap = (config as { sourcemap?: boolean | 'hidden' | 'inline' }).sourcemap;
+
+  if (userSourcemap === false) {
     // eslint-disable-next-line no-console
     console.warn(
       '[@sentry/nitro] You have explicitly disabled source maps (`sourcemap: false`). Sentry will not upload source maps, and errors will not be unminified. To let Sentry handle source maps, remove the `sourcemap` option from your Nitro config, or use `sourcemaps: { disable: true }` in your Sentry options to silence this warning.',
     );
     return { sentryEnabledSourcemaps: false };
   }
 
+  if (userSourcemap === 'inline') {
+    // eslint-disable-next-line no-console
+    console.warn(
+      '[@sentry/nitro] You have set `sourcemap: "inline"`. Inline source maps are embedded in the output bundle, so there are no `.map` files to upload. Sentry will not upload source maps. Set `sourcemap: "hidden"` (or leave it unset) to let Sentry upload source maps and un-minify errors.',
+    );
+    return { sentryEnabledSourcemaps: false };
+  }
+
   let sentryEnabledSourcemaps = false;
-  if (config.sourcemap === true) {
+  if (userSourcemap === true || userSourcemap === 'hidden') {
     if (moduleOptions?.debug) {
       // eslint-disable-next-line no-console
-      console.log('[@sentry/nitro] Source maps are already enabled. Sentry will upload them for error unminification.');
+      console.log(
+        `[@sentry/nitro] Source maps are already enabled (\`sourcemap: ${JSON.stringify(userSourcemap)}\`). Sentry will upload them for error unminification.`,
+      );
     }
   } else {
     // User did not explicitly set sourcemap, enable hidden source maps for Sentry.
-    // Nitro types `sourcemap` as `boolean`, but it forwards the value to Vite which supports `'hidden'`.
     // `'hidden'` emits .map files without adding a `//# sourceMappingURL=` comment to the output, avoiding public exposure.
     (config as { sourcemap?: unknown }).sourcemap = 'hidden';
     sentryEnabledSourcemaps = true;

packages/nitro/test/sourceMaps.test.ts

@@ -215,6 +215,25 @@ describe('configureSourcemapSettings', () => {
     expect(result.sentryEnabledSourcemaps).toBe(false);
   });
 
+  it('keeps sourcemap "hidden" when user already set it and does not enable deletion', () => {
+    const config = { sourcemap: 'hidden' } as unknown as NitroConfig;
+    const result = configureSourcemapSettings(config);
+
+    expect((config as { sourcemap?: unknown }).sourcemap).toBe('hidden');
+    expect(result.sentryEnabledSourcemaps).toBe(false);
+  });
+
+  it('keeps sourcemap "inline", warns, and does not enable uploads', () => {
+    const warnSpy = vi.spyOn(console, 'warn').mockImplementation(() => {});
+    const config = { sourcemap: 'inline' } as unknown as NitroConfig;
+    const result = configureSourcemapSettings(config);
+
+    expect((config as { sourcemap?: unknown }).sourcemap).toBe('inline');
+    expect(result.sentryEnabledSourcemaps).toBe(false);
+    expect(warnSpy).toHaveBeenCalledWith(expect.stringContaining('`sourcemap: "inline"`'));
+    warnSpy.mockRestore();
+  });
+
   it('disables experimental sourcemapMinify', () => {
     const config: NitroConfig = {};
     configureSourcemapSettings(config);