struggling with relative imports

[dckc]

I have the following layout:

src/kernel/index.js
test/test-kernel-xs/main.js
test/test-kernel-xs/manifest.json

In main.js I'd like to use import buildKernel from '../../src/kernel/index'; because that way my editor (vs-code) will know what I'm talking about.

I can't figure out what to put in manifest.json to get mcconfig to play along (with cwd = test/test-kernel-xs). Clues?

With manifest 1 below, I can build and run, but I get:

# Break: (host): module "../../src/kernel/index" not found

with manifest 2, mcconfig -d -m -p lin says ### Error: No such file or directory.
strace output includes:

[pid 27019] mkdir("/home/connolly/projects/moddable/build/tmp/lin/debug/mc/test-kernel-xs", 0755) = -1 EEXIST (File exists)
[pid 27019] mkdir("/home/connolly/projects/moddable/build/tmp/lin/debug/mc/test-kernel-xs/modules", 0755) = -1 EEXIST (File exists)
[pid 27019] mkdir("/home/connolly/projects/moddable/build/tmp/lin/debug/mc/test-kernel-xs/modules/../../src/kernel", 0755) = -1 ENOENT (No such file or directory)

Manfest 1

{
    "include": [
        "$(MODDABLE)/examples/manifest_base.json"
    ],
    "modules": {
        "*": [
            "./main",
            "../../src/kernel/*"
        ],
        "@agoric/harden": "../../node_modules/@agoric/harden/dist/harden.esm",
        "@agoric/make-hardener": "../../node_modules/@agoric/make-hardener/index",
        "@agoric/nat": "../../node_modules/@agoric/nat/dist/nat.esm",
        "tape-promise/tape": "../../node_modules/tape-promise/index.compiled",
        "onetime": "../../node_modules/onetime/index"
    }
}

Manifest 2

{
    "include": [
        "$(MODDABLE)/examples/manifest_base.json"
    ],
    "modules": {
        "*": [
            "./main"
        ],
        "../../src/kernel/*": "../../src/kernel/*",
        "@agoric/harden": "../../node_modules/@agoric/harden/dist/harden.esm",
        "@agoric/make-hardener": "../../node_modules/@agoric/make-hardener/index",
        "@agoric/nat": "../../node_modules/@agoric/nat/dist/nat.esm",
        "tape-promise/tape": "../../node_modules/tape-promise/index.compiled",
        "onetime": "../../node_modules/onetime/index"
    }
}

I guess I can attach a .zip of my working dir...

[dckc]

SwingSet.zip

[phoddie]

I'd like to use import buildKernel from '../../src/kernel/index';

The module specifier in the Moddable SDK is not a path. Trying to make it behave as one isn't going to be easy.

Environment variables are supported in the manifest (the use of $(MODDABLE) is an example of that). Perhaps define one for your src/kernel directory (e.g. $SK), then your editor can resolve that (import foo from "$SK/foo").

[dckc]

vs-code doesn't seem to grok environment variables... but using jsconfig.json looks feasible.

[dckc]

I can do stuff like $SK in the xs-specific parts of what I'm doing, but the goal I'm working on is to get a bunch of existing code, originally developed using node.js, to work in xs.

Maybe there's a way to transpile the import paths... the inverse of babel-plugin-module-resolver... maybe babel-plugin-import-redirect.

Ouch.

[phoddie]

...but the goal I'm working on is to get a bunch of existing code, originally developed using node.js, to work in xs.

Good luck. Moving code written for a large environment with a countless runtime options and a huge tooling ecosystem to a small environment designed embedded devices is a perilous undertaking. Going the other way is generally easier.

Consequently, I would start by finding a away to make the code work well for the more constrained target (e.g. XS). Once that works well, then go back to figure out how to create a single code base that works well for both environments.

[dckc]

It was more the linter than the editor that was confused about relative imports. I found a way to make it happy. It involves changes such as the following in kernel/kernel.js, but my collaborators seem OK with it:

-import { makeLiveSlots } from './liveSlots';
+import { makeLiveSlots } from 'kernel/liveSlots';

dckc/SwingSet@bcc368e

[dckc]

The platform docs show that fxFindModule is platform-specific. The default implementation seems to handle ./ and ../ but stops there, without support for ../../:

https://github.com/Moddable-OpenSource/moddable/blob/public/xs/sources/xsPlatforms.c#L177-L187