Is there a difference in module creation if I use export * instead of export {Component1,...

I recently ran into a failing test where I received the following error message"

TypeError: Cannot redefine property: getCurrentRouteSnapshot


I read the following StackOverflow and found this could be a result of __esModule being false, leading to the import not being configurable. jest spyOn not working on index file, cannot redefine property.

While the solution there worked, it felt like a bit of a bandaid fix, and I was curious why __esModule was false in the first place.

My index file that exports that helper function contains the following:

export * from './router.tools';


I looked into my tsconfig.spec.json, which looks like the following:

{
"extends": "./tsconfig.json",
"compilerOptions": {
"outDir": "../../dist/out-tsc",
"module": "CommonJS",
"target": "ES2016",
"types": ["jest", "node", "chart.js"],
"allowJs": true,
"esModuleInterop": true,
"allowSyntheticDefaultImports": true
},
"include": ["src/**/*.spec.ts", "../../types/**/*"]
}


I noticed that "module" was set to "CommonJS".

When I was looking into CommonJS export standards, I wasn't seeing anywhere that would use export *.

How export all variable on commonjs from deferent file in one place

I changed my index.ts to instead export the following (All exports individually):

export {getCurrentRouteSnapshot, GetCurrentApplication, routeToProbeFeature, ApplicationType, MonitorableTab} from './router.tools';


This fixed the failing test.

Why would export * lead to this not being configurable, but export {/*All Modules*/} does not?

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