module resolve failed with dynamic import and circulated import

[Fenzland]

Files like this:

// index.js
import ('./b.js');
import ('./a.js');

// a.js
import './b.js';

// b.js
import './c.js';
import './a.js';

// c.js
import './d.js';

// d.js

Then lets run with

deno --allow-read index.js

It crash with:

error: Uncaught Cannot resolve module "./d.js" from "file:///tmp/c.js"

Let's edit b.js to this

// b.js
import './a.js';
import './c.js';

Then run

deno --allow-read index.js

It crash with:

error: Uncaught Cannot resolve module "./c.js" from "file:///tmp/b.js"

• when we dynamically import b.js and a.js in index.js concurrently, and b.js first;
• and a.js and b.js statically import each other;
• then we cannot statically import anything in b.js after import a.js.
• and we cannot statically import anything in c.js that imported by b.js before b.js import a.js.

// b.js
import './a.js';
// cannot statically import anything here

// c.js
// cannot statically import anything here

This BUG exists since we support import(). I've encountered it several times.
The first time is under 0.15 or 0.16. Today I, finally find out how to reproduce it.

[lucacasonato]

@Fenzland Can you still reproduce this? This might have been resolved by the module graph refactor @bartlomieju did a while ago.

[bartlomieju]

It was not, this error is still valid. Waiting on modules refactor in core/ by @piscisaureus