[XeTeX] \XeTeXpdffile causes over-long line unless wrapped in \hbox

[Jonathan Kew]

On 15/04/2021 15:24, David Carlisle wrote:
> The command is scanning ahead for keywords such as  page 2 in the 
> unhboxed case 

Shouldn't the \relax stop it scanning ahead anyway?

> but in the boxed case the } stops the scan but it seems 
> having decided that  test is not a keyword it is inserting a space 
> before it which seems wrong. More surprising is that it eats ! here even 
> though  ! isn't part of the allowed syntax as far as I can see
> 
> 
> \def\imga{\hbox{\XeTeXpdffile "image.pdf"\relax!}}
> \def\imgb{\XeTeXpdffile "image.pdf"\relax!}
> 
> 
> 
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> \imga
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> 
> 
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> \imgb
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> test test test test test test test test test test test test test
> 
> \end
> 
> 
> The effect on linebreaking is more or less accidental "test" can't be 
> hyphenated so it's not surprising that some lines can not be justified, 
> and the extra space or not space after the image is changing the 
> linebreaking in the paragraph.
> 
> David
> 
> 
> 
> On Thu, 15 Apr 2021 at 14:24, Gavin Smith <gavinsmith0123 at gmail.com 
> <mailto:gavinsmith0123 at gmail.com>> wrote:
> 
>     If I XeTeX to display an image in text, like
> 
>     \def\img{\XeTeXpdffile "image.pdf"\relax}
> 
>     test test test test test test test test test test test test test
>     test test test test test test test test test test test test test
>     test test test test test test test test test test test test test
>     test test test test test test test test test test test test test
>     \img
>     test test test test test test test test test test test test test
>     test test test test test test test test test test test test test
>     test test test test test test test test test test test test test
>     test test test test test test test test test test test test test
> 
>     \end
> 
>     and then process with "xetex test.tex" on the command line, then the
>     line
>     after the image is too long and goes into the margin.  You can see this
>     in the attached file.
> 
>     I found wrapping the \XeTeXpdffile in an \hbox, thus:
> 
>     \def\img{\hbox{\XeTeXpdffile "image.pdf"\relax}}
> 
>     fixed the problem, but I don't see why this should be necessary.
> 
>     Is this a bug?
> 
>     XeTeX reports its version as follows:
> 
>     $ xetex test.texi
>     This is XeTeX, Version 3.14159265-2.6-0.99998 (TeX Live 2017/Debian)
>     (preloaded format=xetex)
>       restricted \write18 enabled.
>     entering extended mode
>     (./test.texi [1] )
>     Output written on test.pdf (1 page).
>     Transcript written on test.log.
>