[loadable-components] Skipping transform for `ssr: false` breaks SSR with every published `@loadable/component`

[Themezv]

Summary

Since #592 ("fix(loadable-components): skip transformation when ssr: false is specified"), @swc/plugin-loadable-components no longer transforms loadable(fn, { ssr: false }) call sites. This breaks server-side rendering at runtime for every published version of @loadable/component (checked 5.15.3 and latest 5.16.7): the server throws

Invariant Violation: loadable: SSR requires `@loadable/babel-plugin`, please install it

for any ssr: false component rendered under a ChunkExtractor, turning whole pages into HTTP 500s.

The skip is present in all releases containing #592, including the current latest 11.19.0.

Root cause

@loadable/component's runtime checks the transform metadata before it looks at options.ssr. From dist/cjs/loadable.cjs.js (identical in 5.15.3 and 5.16.7):

function InnerLoadable(props) {
  // ...
  invariant(!props.__chunkExtractor || ctor.requireSync,
    'SSR requires `@loadable/babel-plugin`, please install it'); // <-- fires first

  if (props.__chunkExtractor) {
    // This module has been marked with no SSR
    if (options.ssr === false) {
      return _assertThisInitialized(_this);   // <-- ssr:false handled only after the invariant
    }
    // ...
  }
}

So under SSR (__chunkExtractor present), an untransformed ssr: false call site hits the invariant and throws. ssr: false is a runtime rendering decision (render the fallback on the server); it does not mean the call site may be left untransformed.

The reference implementation agrees: @loadable/babel-plugin (5.16.0, latest) transforms these call sites unconditionally — its source does not mention ssr at all. The client-side runtime also uses the metadata (isReady/chunkName) that the transform provides.

Reproduction

Input:

import loadable from '@loadable/component';
const A = loadable(() => import('./a'), { ssr: false });
export default A;

Transform with @swc/plugin-loadable-components >= the release containing #592:

• Actual: the call is left untouched (no requireAsync/requireSync/chunkName object). Rendering <A /> inside ChunkExtractor.collectChunks() then throws Invariant Violation: loadable: SSR requires @loadable/babel-plugin → 500.
• Expected (matches @loadable/babel-plugin and this plugin before fix(loadable-components): skip transformation when ssr: false is specified #592): the first argument is replaced with the metadata object; at runtime ssr: false makes the server render the fallback, as documented.

The same input through @loadable/babel-plugin@5.16.0 produces the full transform.

Note on #465

#592 was made to fix #465 ("loadable-components plugin does not support ssr false"), but the linked docs feature ("Disable SSR on a specific loadable") does not require skipping the transform — with @loadable/babel-plugin the call site is transformed and the runtime handles ssr: false by rendering the fallback on the server. Skipping the transform is what actually breaks ssr: false support: before #592 the plugin handled ssr: false exactly like babel does; after #592 it crashes SSR.

Suggested fix

Revert #592 (i.e. remove has_ssr_false and the early return in transform_import_expr). If skipping is ever desired as an optimization, it can only be done together with a runtime that checks options.ssr === false before the invariant — no published @loadable/component does that.

Happy to send a PR with the revert.