Re: [RFC] Automatic 'make check' in CI

[David Kastrup]

Jonas Hahnfeld <hahnjo@hahnjo.de> writes:

> Nope, that was a red herring: The reason is that the footnote creation
> process in footnote-volta-spanner.ly messes with (point-stencil), which
> is used by skyline-point-extent.ly and also the BendSpanner. As far as
> I understand the Stencil class, its objects are not immutable...
>
> One of the following two changes fixes the problem in my local test
> scenario:
>
> ---
> diff --git a/ly/music-functions-init.ly b/ly/music-functions-init.ly
> index 13f5c37811..17f14b1f07 100644
> --- a/ly/music-functions-init.ly
> +++ b/ly/music-functions-init.ly
> @@ -538,7 +538,7 @@ to the preceding note or rest as a post-event with 
> @code{-}.")
>                 'X-offset (car offset)
>                 'Y-offset (cdr offset)
>                 'automatically-numbered (not mark)
> -               'text (or mark (make-null-markup))
> +               'text (or mark (ly:make-stencil "" '(0 . 0) '(0 . 0)))
>                 'footnote-text footnote)))
>       (once (propertyTweak 'footnote-music mus item))))
>  
> diff --git a/scm/define-markup-commands.scm b/scm/define-markup-commands.scm
> index f7280f7a58..1ab6eaafe3 100644
> --- a/scm/define-markup-commands.scm
> +++ b/scm/define-markup-commands.scm
> @@ -1379,7 +1379,8 @@ An empty markup with extents of a single point.
>    \\null
>  }
>  @end lilypond"
> -  point-stencil)
> +  ;; Create a new point-stencil every time, it might get modified...
> +  (ly:make-stencil "" '(0 . 0) '(0 . 0)))
>  
>  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
>  ;; basic formatting.
> ---
>
> My gut feeling is that we should fix null-markup because nothing should
> ever translate / rotate / modify the global point-stencil, thoughts?

To me that seems crazy.  Instead \footnote should not modify the stencil
generated from its argument in place.  If it needs something with
different dimensions, it needs to create a new stencil, copying the
stencil expression and changing the dimensions.

ly:stencil-set-extent! has been removed in 2.5.17.  Extents are not
intended to be mutable as far as I can discern, so if our C++ code does
violate that assumption, it is that code we should fix instead of giving
up on behavior guaranteed from the Scheme side of things.

-- 
David Kastrup