context method emitFile() is not supported in serve mode. This plugin is likely not vite-compatible.

[code-masala]

Describe the bug

I try to use this.emitFile like this

transform() {
      const css = sample(allPaths);
      this.emitFile({
        type: "asset",
        source: css,
        id: "",
        fileName: "atomic.css",
      });
    },

but emitfile is not generated a d gives warning:
context method emitFile() is not supported in serve mode. This plugin is likely not vite-compatible.
(In rollup this.emitFile is used with generateBundle instead of transform)

Is there any Changes in vite because I take the reference from rollUp

Reproduction

.

System Info

"vite": "^2.8.1"

Used Package Manager

npm

Logs

No response

Validations

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• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Make sure this is a Vite issue and not a framework-specific issue. For example, if it's a Vue SFC related bug, it should likely be reported to https://github.com/vuejs/core instead.
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• The provided reproduction is a minimal reproducible example of the bug.

[bluwy]

Is emitting the file required in serve/dev mode? Vite logs a warning as emitting a file in serve mode doesn't make sense (all files are kept in memory), but it will work in builds as that's a normal rollup process. If your plugin is for builds only, you can set apply: 'build' in your plugin.

[code-masala]

@bluwy does this only work build mode?
Because this is not even generating the file.

[bluwy]

Yeah emitFile only works in build mode (where rollup is involved). I'm not sure if it's possible to call emitFile in the transform hook, maybe that's the issue. You can try calling it in buildStart or generateBundle according to the docs.

[code-masala]

@bluwy is any alternative of emitFile to use in dev mode

[bluwy]

You can use fs.writeFile, but it really depends on your goal here. In some cases virtual modules would work too (link is from Vite, but it's a general pattern in rollup, just that Vite has more examples).

PS: Closing this as this is expected behaviour from Vite, and is leaning towards a discussion.

[code-masala]

generateBuild is also not calling .
Is this due to dev?

[bluwy]

There is no generateBundle in dev mode.