Change camelize behavior

[TylerPachal]

👋 I have a view which has a field which I treat as an "opaque object" which I store as a map. Something like this:

defmodule MyApp.Foobar do

  # ...
  schema "foobars" do
    field :location, :map
  end
end

defmodule MyAppWeb.FoobarView do
  use JSONAPI.View, type: "foobars"

  def fields do
    [
      :location
    ]
  end
end

In my postgres database, an example value looks something like (note the camelCased localizedAddress field):

{
  "country": "China",
  "localizedAddress": null
}

The problem is that after this data flows out of my view, the resulting payload looks like this, where the localizedAddress key has become localizedaddress:

{
    "data": {
        "attributes": {
            "location": {
                "country": "China",
                "localizedaddress": null
            }
        }
    }
}

---

I have pinned it down to the String module:

iex(1)> JSONAPI.Utils.String.camelize("localizedAddress")
"localizedaddress"

---

If changing the String module is too disruptive/risky, then I think there should be a new callback in the view that is a mechanism for giving a value for a field, but without any further transformations applied to it. I.e. today if I do this:

defmodule MyAppWeb.FoobarView do
  use JSONAPI.View, type: "foobars"

  def fields do
    [
      :location
    ]
  end
  
  # This doesn't work: whatever I do here doesn't matter because the downstream string module will still make its changes
  def location(%{location: location}, _conn) do
    location
  end

  # Maybe something like this, but with a better name
  def location_value(%{location: location}, _conn) do
    location
  end
end

[TylerPachal]

Annotation: New test to prove an already-camelized value will remain camelized.

[TylerPachal]

Annotation: Using trim: true means we can remove the need to manually filter out the empty strings.

[TylerPachal]

Annotation: This is the main change. Like the comment says, if we could not split the value into multiple words (i.e. there were no - or _ delimiters) then return the single word without downcasing it.

[mattpolzin]

This looks great; thanks! I am comfortable considering this a bug fix; I can't imagine anyone would consider the current behavior of "lowercasing when already camalized" a feature.

It would help if you bumped the version in the mix.exs file to 1.5.1 as part of this PR because it can currently take quite a while to get version-bump PRs merged which could delay us getting this fix into a release!

[TylerPachal]

@mattpolzin Bumped the version! Thanks for your comment.