Avoid injecting unnecessary preload function if no dependencies are found in glob import

[felixcicatt]

Description

I have a very small entry file, which does a lazy glob import. None of the files that are resolved by this glob import have dependencies.

Vite injects a function in the output, that allows preloading any dependencies. However, this code is never used. This results in the output size being doubled, so this seems wasteful.

Suggested solution

It seems this code is injected as part of the buildImportAnalysisPlugin. It would be nice if the plugin was smart enough to detect if no async imports have any dependencies. In that case, the values of the object that import.meta.glob injects would not need to be wrapped with the preload function, and the preload function itself would not need to be injected. The following example is minified, but I think it's still sufficiently readable:

In stead of:

// ... injected preload functions
p = Object.assign({
    "./components/tab-list.js": () => h(() => import("./tab-list-941ff699.js"), []),
}),

You would just get:

p = Object.assign({
    "./components/tab-list.js": () => import("./tab-list-941ff699.js"),
}),

Alternative

No response

Additional context

No response

Validations

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[sapphi-red]

Duplicate of #13952