Alias plugin not working with swc plugin.

[jpanduro-blackbird]

I might be missing something, but we recently replaced our terser plugin with rollup-plugin-swc and @rollup/plugin-alias stop working.

Here is our configuration

const swcConfig = {
  include: ['src/**/*.ts', '../shared/**/*.ts'],
  exclude: ['src/**/*.test.ts'],
  jsc: {
    parser: {
      syntax: 'typescript',
    },
    target: 'es2015',
    externalHelpers: false,
    minify: { sourceMap: true },
  },
  minify: true,
  sourceMaps: true,
};
const pluginsForNoUAParser = [
  typescript({
    include: ['src/**/*.ts', '../shared/**/*.ts'],
    exclude: ['src/**/*.test.ts'],
  }),
  replace({
    values: replaceConfig[env],
    preventAssignment: true,
  }),
  alias({
    entries: [{ find: 'ua-parser-js', replacement: './src/null.js' }],
  }),
  commonjs(),
  nodeResolve(),
  swc(defineRollupSwcOption(swcConfig)),
];

Any suggestions or ideas would be helpful!

[SukkaW]

rollup-plugin-swc3 acts more as an alternative to @rollup/plugin-typescript rather than rollup-plugin-terser. If you intend to replace terser, you could import swcMinify from rollup-plugin-swc3 instead.

[jpanduro-blackbird]

I think the following config is already doing the minification by lines

jsc: {
    minify: { sourceMap: true }
  },
  minify: true,

Our intent is to not include ua-parser-js library in the bundle in certain cases because of its size. For those purposes we were using @rollup/plugin-alias, which replace it with mocked module, that returned null. And this plugin stopped working after starting using rollup-plugin-swc3

Is there any idea how I can solve this problem?

[SukkaW]

Is there any idea how I can solve this problem?

Could you provide a minimum reproduction so I can pinpoint the issue?

rollup-plugin-swc3 has implemented a customized module resolving to work with TypeScript files while @swc/core can expand aliased imports during the transformation. Although I suspect that this might be the cause of the issue, I can't rectify it without a minimal reproduction.

In the meantime, swcMinify doesn't include a customized module resolving and swc transformation. Therefore simply importing swcMinify from rollup-plugin-swc3 might be the quickest workaround for this issue.

[jpanduro-blackbird]

Thanks for suggestions! Basically, I was able to achieve it by using rollup-plugin-ignore instead