Provide an optional argument for loadConfigFromFile() to avoid leaving temporary file in user workspace

[zhangyx1998]

Description

Although current implementation is already invulnerable to exceptions from the imported userConfig (using finally statememt), it can still leave the temporary file undeleted when user hits CTRL-C on server start (this happens randomly)

See this issue: vuejs/vitepress#3382

Suggested solution

Provide an additional optional parameter to specify where to save the temporary file so downstream frameworks can save temp file to their cache folder.

Example:

export async function loadConfigFromFile(
  configEnv: ConfigEnv,
  configFile?: string,
  configRoot: string = process.cwd(),
  logLevel?: LogLevel,
  tempDir?: string = configRoot, // 👈 suggested change
): Promise<{
  path: string
  config: UserConfig
  dependencies: string[]
} | null> { /* ... */ }

Alternative

1. Instead of writing the file to disk and then importing it back dynamically, transform the code into an IIFE and use eval() to run it.

2. Mask SIGINT before import and unmask it in the finally block.

Additional context

As discussed in the issue (link above), moving bundled file to a different path could mess up relative imports (or requires).

However, it seems like the bundling process always produces a monolithic file without any external dependency (as it is supposed to). My theory is, as long as the process's current working directory doesn't change, nothing should break.

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[sapphi-red]

We cannot just write to a different directory otherwise the relative/bare imports will be resolved to a different file.
There an issue about the temporary file and I believe solving the issue rather than adding an option is better.
See #13269 and #13267 (comment) for the idea of using data: import specifier.

[zhangyx1998]

We cannot just write to a different directory otherwise the relative/bare imports will be resolved to a different file. There an issue about the temporary file and I believe solving the issue rather than adding an option is better. See #13269 and #13267 (comment) for the idea of using data: import specifier.

Thanks for the information!

BTW, may I ask about the rationale of bundling user config? That is, if user config is also ESM, why not use dynamic import directly?

[sapphi-red]

BTW, may I ask about the rationale of bundling user config? That is, if user config is also ESM, why not use dynamic import directly?

It is to collect the dependency information (#5779).