Re: Automated test on PDF or SVG output

[Paolo Prete]

Thank you Dan and Jean.
I'll do some experiments in the next few days and I'll update you.

On Tue, Nov 15, 2022 at 2:39 AM Dan Eble <dan@lyric.works> wrote:

> On Nov 14, 2022, at 04:43, Paolo Prete <paolopr976@gmail.com> wrote:
> >
> > I need to execute the following automated test:
> > given a .ly file, I would like to check if the produced output is what I
> > expect it to be.
>
> For checking the impact of LilyPond changes on my own scores, I use a
> Docker container and a bash script that does this:
>
> 1. reads PDF files from two directories recursively
> 2. converts each page to a bitmap
> 3. overlays the two versions of each page so that pixels which are white
>    in one and black in the other become either red or green
> 4. collates the new images into new PDF files in a third directory
>
> Then I review every score.
>
> It works well when specific things have moved, appeared, or disappeared.
> It can be quite noisy when there have been general changes to spacing.
>
> If that appeals to you, I can send you the scripts privately.
> —
> Dan
>
>