Support for auto renaming nodes with the same name in the bundle

[gfmio]

Bug report

Input code

// template1.ts
const TEMPLATE = "template1";
export default TEMPLATE;

// template2.ts
const TEMPLATE = "template2";
export default TEMPLATE;

// index.ts
export {default as TEMPLATE1} from "./template1";
export {default as TEMPLATE2} from "./template2";

Expected output

// Generated by dts-bundle-generator v4.3.0

export declare const TEMPLATE1 = "TEMPLATE1";
export declare const TEMPLATE2 = "TEMPLATE2";

export {};

or

// Generated by dts-bundle-generator v4.3.0

declare const TEMPLATE$1 = "TEMPLATE1"
declare const TEMPLATE$2 = "TEMPLATE2"

export declare const TEMPLATE1 = TEMPLATE$1;
export declare const TEMPLATE2 = TEMPLATE$2;

export {};

Actual output

// Generated by dts-bundle-generator v4.3.0

export declare const TEMPLATE = "TEMPLATE1";
export declare const TEMPLATE = "TEMPLATE2";

export {};

Console output:

$ dts-bundle-generator ./src/index.ts
Compiling input files...
Processing ./src/index.ts
Writing ./src/index.ts -> src/index.d.ts
Checking generated files...
src/index.d.ts(3,22): error TS2451: Cannot redeclare block-scoped variable 'TEMPLATE'.
src/index.d.ts(4,22): error TS2451: Cannot redeclare block-scoped variable 'TEMPLATE'.

Error: Compiled with errors
error Command failed with exit code 1.

Additional context
Add any other context about the problem here (CLI options, etc)

dts-bundle-generator will throw errors when you use the same variable name more than once. This is presumably, because the script only concatenates the files and does not perform an analysis of name collisions.

However, the API surface of the module is also incorrect, because the wrong names are exported. I'm not sure if this is just due to the name clash or because of an underlying issue.

I'm using dts-bundle-generator 4.3.0 and typescript 3.8.3.

[gfmio]

I just renamed my variables and the bundle is constructed properly, but the exported names are still wrong.

Input code

// template1.ts
const TEMPLATE$1 = "template1";
export default TEMPLATE$1;

// template2.ts
const TEMPLATE$2 = "template2";
export default TEMPLATE$2;

// index.ts
export {default as TEMPLATE1} from "./template1";
export {default as TEMPLATE2} from "./template2";

Actual output:

// Generated by dts-bundle-generator v4.3.0

export declare const TEMPLATE$1 = "TEMPLATE1"
export declare const TEMPLATE$2 = "TEMPLATE2"

export {};

[timocov]

It looks like the second limitation, isn't it? I'll check what we can do here, but for now you can use workaround:

// index.ts
import TEMPLATE1 from "./template1";
import TEMPLATE2 from "./template2";

export { TEMPLATE1, TEMPLATE2 };

(and the same names in template files)

[gfmio]

Maybe I misunderstood the 2nd limitation, but I thought that only applies when re-exporting a default export as a default export.

The workaround worked though, and it actually still works, even if both variables are named TEMPLATE as long as they are imported using and exported with different names.

[timocov]

Maybe I misunderstood the 2nd limitation, but I thought that only applies when re-exporting a default export as a default export.

Yeah, I've thought it is so 😂 Looks like the issue is with default exports in common.

From the beginning dts-bundle-generator never changed the original names of classes/variables/etc, that's why you faced this issue (and I personally never though that it's a big deal to fix it in your code because it's just renaming and you can handle error while generating the bundle). Maybe it needs to be changed and start renaming them somehow, but I guess it isn't easy to do (I'd like to use TypeScript API here, but afaik there is no API for that).

It might be I can (easily) fix the issue from #116 (comment) in the way:

declare const TEMPLATE$1 = "TEMPLATE1";
declare const TEMPLATE$2 = "TEMPLATE2";

export { TEMPLATE$1 as TEMPLATE1, TEMPLATE$2 as TEMPLATE2 };

export {};

but I can't tell you for sure.

[timocov]

The fix has been released in v9.0.0.