[Bug]: mainFiles autoExtensions bad case "./components/button/index.js"

[SoonIter]

Version

rslib 0.0.8

Details

.
├── src
│   ├── button
│   │   └── index.tsx
│   └── index.ts
└── tsconfig.json

input

// index.ts
import button from './button';

expected behavior

import button from './button/index.mjs';

actual behavior

import button from './button.mjs';

Reproduce link

none

Reproduce Steps

none

[SoonIter]

By the way, in bundless mode, if cannot resolve, error message should be emitted

[fi3ework]

Does other tools support patch mainFiles in bundleless mode as of now? For bundle mode, support index in mainFields is fine. In bundleless mode, I feel it's too lose somehow.

[SoonIter]

Does other tools support patch mainFiles in bundleless mode as of now? For bundle mode, support index in mainFields is fine. In bundleless mode, I feel it's too lose somehow.

modernjs module does not support it yet, but its autoExtensions default value is false

[fi3ework]

esbuild by default could handle index mainFiles, but when the target module is externalized, it will not adding index as well.

https://esbuild.github.io/try/#YgAwLjI0LjAALS1idW5kbGUgLS1mb3JtYXQ9ZXNtIC0tZXh0ZXJuYWw6Jy4vYScAZQBlbnRyeS5qcwBpbXBvcnQgeCBmcm9tICcuL2EnCmV4cG9ydCB7IHggfQAAYS9pbmRleC5qcwBleHBvcnQgZGVmYXVsdCA1

If we wish to support this feature, we need to use getResolve in the external function to get the resolved path, but currently getResolve is not supported.

I think we can temporarily disable mainFiles in bundleless mode to avoid this too loose behavior.

[Timeless0911]

Same as #238, we should check whether getResolve hook in Rspack will be supported in the nearly future.

[Timeless0911]

We should also handle when ./folder/index.ts and ./folder.ts exists at the same time, there may also be .ts, .tsx, .jsx file existing.

[fi3ework]

We should also handle when ./folder/index.ts and ./folder.ts exists at the same time

We could just follow Rspack's default order.

there may also be .ts, .tsx, .jsx file existing.

getResolve could handle all of these.

[joshwooding]

Is there an issue to follow for this? Or a quick way to catch this issue? You mentioned disabling mainFiles?

[Timeless0911]

Is there an issue to follow for this? Or a quick way to catch this issue? You mentioned disabling mainFiles?

You can write the full path when writing source code to avoid this issue.

- import button from './button';
+ import button from './button/index';

[joshwooding]

Is there an issue to follow for this? Or a quick way to catch this issue? You mentioned disabling mainFiles?

You can write the full path when writing source code to avoid this issue.

• import button from './button';

• import button from './button/index';

The hard part is finding them all :) So was wondering if there was a quick way, I'll look into it thanks!

[fi3ework]

There's not a rational way to find the /index by leveraging Rspack without getResolve function, there are some workarounds such as manually check before resolving, but that's a bypass implementation which is an alternative to mainFiles. We haven't decided the implementation as getResolve might can't be supported due to the perf consideration.

[joshwooding]

Thanks for the quick response, makes sense. I guess #251 will help flag these issues.