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Cyclic dependencies are broken with module instance objects

See original GitHub issue

The following code works fine:

// a.js
import {b} from "./b.js";

export function a() {
  console.log(b);
}

//b.js
import {a} from "./a.js";

export function b() {
  console.log(a);
}

But if we rewrite this using module instance objects the compiler iloops:

// a.js
import * as m from "./b.js";

export function a() {
  console.log(m.b);
}

//b.js
import * as m from "./a.js";

export function b() {
  console.log(m.a);
}

And here is the part of the stack trace that keeps getting called over and over again.

...
	at com.google.javascript.jscomp.modules.EsModuleProcessor$UnresolvedEsModule.resolve(EsModuleProcessor.java:318)
	at com.google.javascript.jscomp.modules.EsModuleProcessor$UnresolvedEsModule.resolveImportImpl(EsModuleProcessor.java:415)
	at com.google.javascript.jscomp.modules.EsModuleProcessor$UnresolvedEsModule.resolveImport(EsModuleProcessor.java:378)
	at com.google.javascript.jscomp.modules.EsModuleProcessor$UnresolvedEsModule.resolveImport(EsModuleProcessor.java:385)
	at com.google.javascript.jscomp.modules.EsModuleProcessor$UnresolvedEsModule.getAllResolvedImports(EsModuleProcessor.java:360)
	at com.google.javascript.jscomp.modules.EsModuleProcessor$UnresolvedEsModule.resolve(EsModuleProcessor.java:318)
	at com.google.javascript.jscomp.modules.EsModuleProcessor$UnresolvedEsModule.resolveImportImpl(EsModuleProcessor.java:415)
	at com.google.javascript.jscomp.modules.EsModuleProcessor$UnresolvedEsModule.resolveImport(EsModuleProcessor.java:378)
	at com.google.javascript.jscomp.modules.EsModuleProcessor$UnresolvedEsModule.resolveImport(EsModuleProcessor.java:385)
	at com.google.javascript.jscomp.modules.EsModuleProcessor$UnresolvedEsModule.getAllResolvedImports(EsModuleProcessor.java:360)
...

Issue Analytics

State:
Created 4 years ago
Comments:6 (6 by maintainers)

Top GitHub Comments

1reaction

jplaistedcommented, May 2, 2019

Just to update: I’ve not really had time to look at this, or so I thought. I was over-complicating a solution, but I think there’s a simpler one. Fix should be out soon.

1reaction

jplaistedcommented, Apr 9, 2019

Thanks, I’ll take a look!

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