plot_crop fails silently

[JackCaster]

I am using knitr via Quarto. One issue that I had was that the pdf plots had too much margin, but I solved it with the knitr::hook_pdfcrop. The thing is that it took me a while to get pfdcrop to work. The problem was that:

• pdfcrop was not installed: solved it with tinytex::tlmgr_install("pdfcrop")
• the PATH was not correctly set in my Ubuntu-based Docker container ($HOME/bin was not in the PATH originally, see https://yihui.org/tinytex/#installation, Install pdfcrop not working on Ubuntu 22 rstudio/tinytex#435, Cannot set/change user binary dir on Linux rstudio/tinytex#365).

Until I fixed the problems above with some trials and errors, knitr::plot_crop was failing silently, returning the path of the image to crop, but not actually cropping.

Would it be a good idea to change this

knitr/R/plot.R

Line 345 in 9eb1074

if (is_pdf && !has_utility('pdfcrop')) return(x2)

into something that raises a warning if the utility is not found?

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[cderv]

It seems it should warn by default as warn = TRUE is the default

knitr/R/utils.R

Line 812 in 9eb1074

if (name == 'pdfcrop') yes = has_crop_tools() else {

knitr/R/utils.R

Lines 821 to 838 in 9eb1074

	has_crop_tools = function(warn = TRUE) {
	if (Sys.which('pdfcrop') == '') {
	if (warn) warning("'pdfcrop' is required but not found")
	return(FALSE)
	}
	if (is_windows() && Sys.which('tlmgr') != '') {
	# assuming users know what this env var means (rstudio/tinytex#391)
	if (Sys.getenv('TEXLIVE_WINDOWS_EXTERNAL_GS') != '') return(TRUE)
	year = tinytex::tlmgr_version('list')$texlive
	if (year < 2023 && warn) warning(
	'TeX Live version too low. Please consider upgrading, e.g., via tinytex::reinstall_tinytex().'
	)
	return(year >= 2023)
	}
	gs = tools::find_gs_cmd() != ''
	if (warn && !gs) warning("'ghostscript' is required but not found")
	gs
	}

Did you get no warning at all ?

I tried tinytex::tlmgr_remove("pdfcrop") to uninstall pdfcrop and then tried

> knitr:::has_utility("pdfcrop")
[1] FALSE
Message d'avis :
Dans has_crop_tools() : 'pdfcrop' is required but not found

and I got the warning.

So maybe this is something else in another context ?