Proposal status: Access AST of the javascript module

[ganeshkbhat]

What is the problem this feature will solve?

Has the Access AST of the javascript module proposal been accepted into tc9 and node.js?

I wish to strongly vote for it, if this is in consideration. I recommend the access using a seperate nodejs module api, if requested for my view. pls consider security and runtime risks based on your immense experience with such an nodejs module api access without a commandline's force access ast option enabled or other secure alternatives.

What is the feature you are proposing to solve the problem?

• Access AST of the javascript module.

What alternatives have you considered?

Using a bundler parser like ESTree, Typescript, and Babel. https://stackoverflow.com/questions/16127985/what-is-javascript-ast-how-to-play-with-it

Seems like a proposal was made to tc9 by babel. [babel](https://github.com/babel/babel/blob/main/packages/babel-parser/ast/spec.md) - supports language features which is have not yet become a standard, but have a [proposal](https://github.com/tc39/proposals). in this answer https://stackoverflow.com/a/66194129/3204942

[bnoordhuis]

I think you misunderstand https://github.com/babel/babel/blob/main/packages/babel-parser/ast/spec.md - it's not a TC39 proposal, it talks about TC39 proposals.

To answer your question: there are no plans to expose a JS parser in node.

Apropos TC39 proposals: once a proposal is accepted, engines start implementing it. Once V8 implements it, it automatically makes its way into node.

I'll go ahead and close this because there's nothing to do on our end but I can convert it to a discussion if you have follow-up questions.

[ganeshkbhat]

@bnoordhuis Can I make a TC39 proposal also?

[bnoordhuis]

See https://tc39.es/ - yes, if you're a member; sort of, if you're not.

[ganeshkbhat]

:) i am in a strong belief that exposing the ast may be beneficial for many other purposes. it is available in python ast

• one use case - capturing runtime dynamic imports (modules) without using a loader like this. access the imported packages cache like require.cache #45206 (comment)
• other use cases being better linters, parsers, runtime checks, runtime manipulation, etc

[ganeshkbhat]

@bnoordhuis I need help to file a TC39. Would you be open to spend a few minutes here to discuss raising the request?

[bnoordhuis]

I'm not involved with TC39 (and don't plan to, either.)

[ganeshkbhat]

@bnoordhuis anyone you recommend me to raise this and help me with this. Do you think considering this for global function and I believe it is a good thought? I do think so. However, this is a risk; but present in python for access. Serious advanced options.

https://docs.python.org/3/library/ast.html

[bnoordhuis]

I don't have any suggestions, I'm afraid.

That said, I strongly suspect a proposal would get rejected, the reasoning being: libraries like acorn and esprima exist so why build that functionality into JS engines?

[ganeshkbhat]

@bnoordhuis acorn and esprima are too big and security concerns are many. I will never use them on live servers. More, having the AST by itself can be a security risk (less a security risk will be a read-only AST), and external packages will even more prone; regardless of who is backing it.

[ganeshkbhat]

+1 Reopening this feature request: #50949

[ganeshkbhat]

+1 Reopening this feature request: v8/v8.dev#717

[ganeshkbhat]

@bnoordhuis adding to this, it seems like/ behaviour none of the variable's, let's, const's, function's declaration made in the code already without using declarations like global.variable is not accessible from globals even as read-only which should not be the case. A presence of this or access to v8/v8.dev#717 or #45158 can lead to better AST or (read-only) access to variables.

I am seeing acorn: 8.10.0 here. What is this and what is the relevance here? Any way to access this in the newer versions of nodejs?

Microsoft Windows [Version 10.0.22631.2861]
(c) Microsoft Corporation. All rights reserved.

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C:\Users\ganes>