`[suspicious-nullish-coalescing]` warning from dead `?? []` fallback in virtual module codegen

[cameronraysmith]

Astro Info

Astro                    v5.16.7
Node                     v24.12.0
System                   macOS (arm64)
Package Manager          bun
Output                   static
Adapter                  @astrojs/cloudflare
Integrations             @astrojs/starlight

If this issue only occurs in one browser, which browser is a problem?

No response

Describe the Bug

JSON.stringify() always returns a string, so nullish coalescing on its interpolated output is dead code.

astro/packages/astro/src/assets/vite-plugin-assets.ts

Line 155 in e73deb8

export const viteFSConfig = ${JSON.stringify(resolvedConfig.server.fs)} ?? {};

astro/packages/astro/src/assets/vite-plugin-assets.ts

Lines 157 to 160 in e73deb8

	export const safeModulePaths = new Set(${JSON.stringify(
	// @ts-expect-error safeModulePaths is internal to Vite
	Array.from(resolvedConfig.safeModulePaths),
	)} ?? []);

When safeModulePaths is empty, this generates:

new Set([] ?? []);

esbuild flags this during bundling (e.g., via wrangler):

▲ [WARNING] The "??" operator here will always return the left operand [suspicious-nullish-coalescing]

Likely introduced in

• fix(assets): Use Vite's isFileLoadingAllowed to check if a file can be loaded #15052

Runtime behavior seems correct.

This could probably be fixed by removing the ?? {} and ?? [] fallbacks entirely, or by guarding the template with emptiness checks.

What's the expected result?

No warning.

Link to Minimal Reproducible Example

decline

Participation

• I am willing to submit a pull request for this issue.

[Princesseuh]

Ah, my fault. If you have the time a PR would be welcome, otherwise I can get to it in the coming days, hopefully!

[kedarvartak]

Hi! I’d like to work on this issue. Could you please assign it to me?

[trueberryless]

Hi! I’d like to work on this issue. Could you please assign it to me?

I am afraid, cameronraysmith already created the fix for this issue in #15140. But feel free to review those changes if you want 🙌