Fix: Add Promise as return type to save method

[malthoff]

The types of the jsPDF.save method only mention jsPDF itself, but if returnPromise options is set to true the function returns a promise.

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[Uzlopak]

Is it a Promise?

[malthoff]

If you provide { returnPromise: true } as options in save, it returns a promise. But the types are not reflecting this change. It was introduced due to this discussion:
#540

[Uzlopak]

lol. Markup changed my question. My original question was:
Is it a Promise<void>?

So do you have to add <void> so that the typings don't throw in modern typescript?

[Uzlopak]

Also i think you can make it more typestrong if you do it like this:

save(filename: string, options: { returnPromise: true }): Promise<void>;
save(filename?: string): jsPDF;

[Uzlopak]

modified accordingly.

[malthoff]

Not sure, as the result of saveAs is returned.

Code:

return new Promise(function(resolve, reject) {
        try {
          var result = saveAs(getBlob(buildDocument()), filename);
          if (typeof saveAs.unload === "function") {
            if (globalObject.setTimeout) {
              setTimeout(saveAs.unload, 911);
            }
          }
          resolve(result);
        } catch (e) {
          reject(e.message);
        }
      });

[Uzlopak]

Yeah but result in FileSaver.js is not return anything i think

[malthoff]

ok, perfect. Thanks for adjusting

[Uzlopak]

@HackbrettXXX
I guess as maintainer, you want to decide regarding merging this PR.

[HackbrettXXX]

Thanks. I'll merge it.