Disable compile time evaluation of import.meta.url

[pavelsavara]

Problem

Current webpack 5 evaluates import.meta.url to file://some/path/to/source of the build machine.

Fixes #14445

Proposed changes

add new parser setting importMeta - enable/disable import.meta parsing

module.exports = {
  module: {
    parser: {
      javascript : { importMeta: false }
    }
  }
};

Does this PR introduce a breaking change?
No

What needs to be documented once your changes are merged?

New parser.javascript option importMeta - enable/disable import.meta parsing

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ Pavel Savara (73bb431)

[webpack-bot]

For maintainers only:

• This needs to be documented (issue in webpack/webpack.js.org will be filed when merged)
• This needs to be backported to webpack 4 (issue will be created when merged)

[alexander-akait]

This options should be implemented on module level, i.e. you can disable it for some modules, example of new URL(...) https://webpack.js.org/configuration/module/#moduleparserjavascripturl

[alexander-akait]

Looks good, can you accept CLA?

[pavelsavara]

Now I tested it that it works for my use case. I also tested that it keeps doing the original substitution by default.
I'm not sure if the other broken tests are relevant or how to fix them.
Could you please help me ?

[alexander-akait]

SyntaxError: Cannot use 'import.meta' outside a module

I think it is lack supported import.meta in tests, because we use vm.runInThisContext, we can:

• Skip test
• Refactor our tests and support it

[alexander-akait]

Run node_modules/.bin/jest test/TestCasesNormal.basictest.js

[pavelsavara]

• Skip test

it.skip() would not work here as it's issue with parsing the module. Any other ideas ?

• Refactor our tests and support it

I guess that something require individual test files ?
To be able to test ES6 modules, we would need to dynamic import it instead.
That should be ok even in vm.runInThisContext I think.

And that only for tests which are for the es6 module target, because things like __filename don't work in es6 module, so we could not switch all tests.

Could you advise what enumerates the test files?
Is that jest ?
https://jestjs.io/docs/ecmascript-modules

[vankop]

@pavelsavara thanks for starting PR, we discussed internally that importMeta: boolean option would be better. I have improved your PR

[pavelsavara]

Cool, feel free to take it over.
I wonder what fixed the SyntaxError: Cannot use 'import.meta' outside a module in the tests ?

[vankop]

not sure, I think syntax error was in vm context that was running without esm enabled

[sokra]

some nitpicks

[webpack-bot]

@vankop Thanks for your update.

I labeled the Pull Request so reviewers will review it again.

@sokra Please review the new changes.

[webpack-bot]

I've created an issue to document this in webpack/webpack.js.org.