Graph does not support multiple imports of the same specifier

[kitsonk]

When doing something like this:

import a from "./a.js";
import * as b from "./a.js";
const c = await import("./a.js");

The dependencies for the module only include one import site. They should actually be two seperate dependency objects, as they "may" differ in ways (like import assertions or type definitions).

That being said, it still works and adding support for it would make everything related to it fairly complex, as knowing the import location would become essential for accessing information (unless we stored a vec of locations, and associated information, like it being a dynamic import and any import assertions).

[devingfx]

Yes I had got the issue with https://esm.sh 's redirect packages:

/* esm.sh - [email protected] */
export * from "https://esm.sh/v117/[email protected]/deno/index.mjs"
export { default } from "https://esm.sh/v117/[email protected]/deno/index.mjs"

With a simple custom naive replacer, you are not able to know the existence of other instance in text, so url replacement fail here:

(pseudo code)

graph.modules.map( m=> {
    m.content = load file in cache folder
    for( const dep of m.dependencies )
        replaceBetweenStartEnd( m.content, dep.code.span, makeLocalhost(dep.specfier) )
})

Produces

/* esm.sh - [email protected] */
export * from "http://localhost:8117/cache/deps/https/..."   << only this one is replaced
export { default } from "https://esm.sh/v117/[email protected]/deno/index.mjs"

[dsherret]

This also matters for doing stuff like:

async function main() {
  const mod1 = require("./a.js");
  const mod2 = await import("./a.js");
}

Or:

import type something from "some-package" with { "resolution-mode": "import" };
import type something from "some-package" with { "resolution-mode": "require" };