Add support for Tz operator (horizontal scaling).

[msbit]

Simple implementation of the Tz operator for allowing horizontal scaling of text.

[pointlessone]

Hello @msbit. Thank you very much for your contribution.

I'll take a closer look at the code a bit later. Meanwhile could you please add a spec or two that cover new code?

[msbit]

Hey @pointlessone. I've based the implementation on character_spacing, and so I was thinking of adding them into a PR for https://github.com/prawnpdf/prawn, as all the character_spacing specs seem to be in place on there. Would that be okay?

[pointlessone]

This is unfortunate consequence of extraction of PDF Core out of Prawn. There isn't always an obvious way to cut it.

Those specs definitely should belong here since the code is in this gem. Could you please file an issue about that since you've already inspected the code?

As for this PR we'd prefer specs here for this code and in Prawn gem for the code that uses this feature if any.

[msbit]

Okay, that sounds fair.

I'll look at the specs for this PR tomorrow, and while I'm investigating that I'll see if I can put together a reasonable overview of what would need to come across in terms of specs from prawn into pdf-core for character_spacing.

[pointlessone]

@msbit Thank you. Much appreciated.

[msbit]

Added specs covering the pdf-core specific parts of this.

[pointlessone]

It probably would be better to move class definition out of before and use let instead to create a new mock for each example.

[msbit]

Yep, that makes sense.

[msbit]

👌