Deno.bundle causes Assertion error in the TS compiler

[littledivy]

Error

Steps to reproduce

const code: string = `
// foo.ts
export * from "./a.ts";
export * from "./b.ts";
`
await Deno.bundle(
        "/foo.ts",
        {
          "/foo.ts": code,
        },
        {
          target: "es3",
          module: "esnext",
        },
  );

where a.ts and b.ts can be any valid typescript module

Deno - 1.4.0
v8 - 8.7.75
typescript - 4.0.2

[kitsonk]

I thought we had an issue for this, but we don't. The title should be deno bundle doesnt support export * exports.

[JordanMajd]

TLDR: I suspect export * from "./a.ts" counts as a redirect, but buildLocalSourceFileCache doesn't respect it.

Additional Notes: Things like export {pickle} from "./jar.ts"; also are affected by this issue.

Pull Request: #7607

Wall of text:
runtimeBundle calls buildLocalSourceFileCache(sourceFileMap) but an assertion fails because the entries in sourceFileMap don't contain any sourceCode.

Removing the assertion removes the error, but the bundle still won't contain the expected exports from foo.ts.

While debugging, I found this could be overcome by replacing the call to buildLocalSourceFileCache with buildSourceFileCache and ensuring that the return's output was never empty output: state.bundleOutput ? state.bundleOutput : {},.

It looks like there are two differences between the functions:

1. buildSourceFileCache ensures that if the imported file is a redirect, the mappedUrl will reflect the redirect.
2. buildLocalSourceFileCache modifies the imports mappedUrl by removing memmory://.

After testing I found that 1. was the issue; export * from "./a.ts"; counts as a redirect, but buildLocalSourceFileCache isn't updating the mappedURL to reflect that.

The solution was:

1. remove the offending assert(entry.sourceCode.length > 0); on line 493.
2. add the following right below line 505's assert(importedFile); to buildLocalSourceFileCache

if (importedFile.redirect) {
  mappedUrl = importedFile.redirect;
}

Repro'd tested the fix with the following: \deno.exe run --unstable --allow-all .\comp.ts

//comp.ts
const code = `
// foo.ts
export * from "./a.ts";
export * from "./b.ts";
`;
await Deno.bundle(
  "/foo.ts",
  {
    "/foo.ts": code,
  },
  {
    target: "es3",
    module: "esnext",
  },
);

//a.ts
export default function(){
}

//b.ts
export default function(){
}

[kitsonk]

For deno bundle this now works, but for Deno.bundle() it requires #8060 so we should keep this open until that.

[kitsonk]

#8060 is resolved... closing.