emscripten-core/emscripten

Faulty assertion in node on .mjs files

Open

#17,465 opened on Jul 18, 2022

View on GitHub
 (4 comments) (0 reactions) (0 assignees)C++ (3,519 forks)batch import
JavaScriptgood first bughelp wanted

Repository metrics

Stars
 (27,361 stars)
PR merge metrics
 (Avg merge 19d 10h) (147 merged PRs in 30d)

Description

It turns out that node will disable the global require function on foo.mjs - that is just not defined there, unlike for foo.js. I guess mjs files are modules and require is not supposed to be used there. This ends up a problem for us since we have an assertion on it:

https://github.com/emscripten-core/emscripten/blob/a3d8979b38d2f655f59b040bfd32f562ebc92d03/src/shell.js#L196-L198

Removing that assertion is necessary to run an .mjs file in node with -sASSERTIONS.

We should probably just remove it?

This happens on binaryen CI which will manually builds an .mjs file by concatenating the emcc output with some extra code.

Contributor guide

Research direction
Inspect the assertion in shell.js line 196-198 and remove it. Verify that the removal does not affect other uses and test with .mjs files in Node with sASSERTIONS.
Tech stack
javascriptnodejs
Domain
tooling
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
1
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Under 1 hour
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
JavaScriptNode.js
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
80