Surprising require('./file') behavior when ran from REPL

[eridal]

Where?

• Version: v10.15.3, v12.13.1, v13.3.0
• Platform: x86_64 GNU/Linux
• Subsystem: require

Repo Steps

Given the following tree:

mkdir testrequire
cd testrequire

mkdir node_modules
echo 'module.exports = `yes`' > node_modules/foo.js

The following code will produce different behavior when executed as a main module, required module, or from the REPL

require('./foo') // this should always throw an error, but works on the REPL

Tests

1. As main module:

↪ echo 'require(`./foo`)' > main.js; node main.js
internal/modules/cjs/loader.js:800
    throw err;
    ^

Error: Cannot find module './foo'

2. As stdin input:

↪ echo 'require(`./foo`)' | node
internal/modules/cjs/loader.js:800
    throw err;
    ^

Error: Cannot find module './foo'

3. As REPL commands:

This is the surprising behavior

↪ node
Welcome to Node.js v12.13.1.
Type ".help" for more information.
> require('./foo')
'yes'

4. As REPL but indirectly loaded

↪ echo 'require(`./foo`)' > main.js
↪ node
Welcome to Node.js v12.13.1.
Type ".help" for more information.
> require('./main')
Thrown:
Error: Cannot find module './foo'

Is this a bug?

I'm not sure if this is a bug or not, but it is quite surprising to me.

I'd expect require to behave the same no matter from where it is being executed. Why is that the REPL behaves differently?

[addaleax]

@eridal I would consider this a bug as well.

(I’ve modified the title since “cli” would more typically refer to node --print .../node --eval ... rather than the REPL interface.)

@nodejs/repl

[ZYSzys]

I think #30835 is able to fix this.