.abort: Don't set headers to default

[nicjansma]

In .abort(), we were setting headers to defaultHeaders. This causes a couple problems.

First, this means you can't set the full User-Agent. Since .open() calls this.abort(), User-Agent will be set after the consumer calls xhr.open(...). If the consumer then calls xhr.setRequestHeader("User-Agent", "foo");, the actual User-Agent would end up as node-XMLHttpRequest, foo instead of just foo because setRequestHeader() appends to the existing value (set by .abort()) if it already exists.

The test-headers.js test actually sets user-agent to node-XMLHttpRequest-test and validates this, but it only works because it sets user-agent and not User-Agent. Since .abort() was just calling headers = defaultHeaders without setting headersCase as well, the test headers ended up as:

{
  "User-Agent": "node-XMLHttpRequest",
  "user-agent": "node-XMLHttpRequest-test"
}

Which would send node-XMLHttpRequest-test over the wire since it was last.

To solve this, I think we can simply not set headers = {} in .abort(), as .send() will set the default headers later anyways.

[nicjansma]

@driverdan Any chance you have time to review these changes?

[nicjansma]

@driverdan Are you no longer maintaining this project? It would be great to get feedback so others know whether they can expect their PRs to be answered or not.

[nicjansma]

@driverdan If you don't have time to review PRs and issues, would you consider adding additional collaborators to help review changes?

[nicjansma]

Would still like to get this merged in

[hmoog]

checkout https://www.npmjs.com/package/xmlhttprequest-ts - i added your pull request

[nicjansma]

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[nicjansma]

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