Fix dialyzer spec for mock opts

[tomekowal]

Hi!

This change is so small that I figured it will be OK to open a PR directly instead of going through issues.

I recently got a dialyzer error:

The created anonymous function has no local return.

for code like this:

mock = fn %{body: body} ->
  json(body, method: method, url: url, status: 200)
end

I was surprised because those mocks worked.
I traced the problem to the dialyzer spec:

https://github.com/elixir-tesla/tesla/blob/master/lib/tesla/mock.ex#L173

and then the change in the PR. The current spec only says headers and status while everything that is in Tesla.Env can be set this way:

https://github.com/elixir-tesla/tesla/blob/master/lib/tesla/mock.ex#L198

(except :body which would be overwritten by the body set as the first parameter to json(body, opts) call)

An alternative way would be to use reflection and say that options are "all Telsa.Env fields except for :body, __module__ and __client__, but I think using reflection could be an overkill.

[Copilot]

Pull request overview

This PR fixes the Dialyzer type spec for mock response options in Tesla.Mock. The previous response_opt type only listed :headers and :status, but the underlying response/3 helper passes all options through to struct(Tesla.Env, ...), meaning any Tesla.Env field (except :body, which is set separately) is valid. This caused false Dialyzer errors when users passed options like :method or :url.

Changes:

• Expanded the @type response_opt to include :method, :query, and :url alongside the existing :headers and :status.

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[yordis]

@tomekowal do you mind fixing the commits 🙏🏻 See CI

[tomekowal]

Fixed the commit message. Thanks for pointing it out!