Dynamic import with extra parenthesis not captured

[privatenumber]

When the dynamic import argument is wrapped in a parenthesis, the statement range is not correctly captured:

import { init, parse } from 'es-module-lexer';

await init;

const source = 'import(("asdf"))';

const [imports] = parse(source, 'optional-sourcename');
const [imp] = imports;
const dynamicImportStatement = source.slice(imp.ss, imp.se);
// import(("asdf")
// Expected to be: import(("asdf"))

if (dynamicImportStatement !== source) {
  console.log('Full statement was not captured:', dynamicImportStatement);
}

Reproduction: https://stackblitz.com/edit/stackblitz-starters-zzxwkp?file=index.mjs

[guybedford]

Hey @privatenumber, yes this is by design - we don't parse arbitrary expressions, so from the perspective of the lexer, ('string') is an expression, while 'string' is a direct static string.

In the dynamic expression cases, you always do just need to apply a custom parser, but at least there is an expression range you can apply it to.

[privatenumber]

The problem is that the expression range is incorrect, which results in invalid JS.

e.g. a parser cannot correctly parse import(("asdf") because it's missing the closing parenthesis ).

[guybedford]

Okay, right, if it’s the wrong offset for a slice function then that’s a buf we should fix.

On Sat, Sep 9, 2023 at 19:04 Hiroki Osame @.***> wrote:

The problem is that the expression range is incorrect, which results in invalid JS.

e.g. a parser cannot correctly parse import(("asdf") because it's missing the closing parenthesis ).

— Reply to this email directly, view it on GitHub https://github.com/guybedford/es-module-lexer/issues/156#issuecomment-1712685926, or unsubscribe https://github.com/notifications/unsubscribe-auth/AAESFSQRNMFG6OW7RIO4FBDXZUN3LANCNFSM6AAAAAA4A2CIP4 . You are receiving this because you commented.Message ID: @.***>

[guybedford]

Released in 1.3.1.

[privatenumber]

Thank you @guybedford !