[Rd] Bracketed paste issues on Linux

[Cesko Voeten]

I am on an up-to-date Arch Linux system, using the GNOME desktop environment. By default, this turns on bracketed paste in terminal emulators; for those not familiar with this concept: it makes it so that if you paste in multiple lines of code, they are received in a single chunk. This works just fine with R, up to a certain amount of text: for chunks past a certain length, some amount of text in the middle of the chunk goes missing. For example, if I print the source of mgcv::gam into my R session and then attempt to copy and paste it back in, what I end up with is:

<snip 53 perfectly good lines>
            pmf$formula <- gp$pf
            pmf <- eval(pmf, parent.frame())
}   objectvironment(attr(object$pred.formula, "full")) <- .GlobalEnv<- environment(object$terms) <- environment(object$pterms) <- .GlobalEnv

So:
 - the first 55 lines in this example arrive perfectly fine
 - then a bunch go completely missing
 - then various parts of the last few lines are jumbled together into one line

For reference on the third point, the actual last 10 lines of my version of mgcv::gam are:
    if (is.null(object$deviance)) 
        object$deviance <- sum(residuals(object, "deviance")^2)
    names(object$gcv.ubre) <- method
    environment(object$formula) <- environment(object$pred.formula) <- environment(object$terms) <- environment(object$pterms) <- .GlobalEnv
    if (!is.null(object$model)) 
        environment(attr(object$model, "terms")) <- .GlobalEnv
    if (!is.null(attr(object$pred.formula, "full"))) 
        environment(attr(object$pred.formula, "full")) <- .GlobalEnv
    object
}

parts of which can be recognized in the last line of what was pasted.
Naturally, the pasted function is not parsed properly: if I press return I get the expected "+" signaling that the REPL is expecting more input. So it is not merely a visual issue.

I can reproduce this both in GNOME Terminal and in xterm, so it is not a bug specific to my terminal emulator. In addition, pasting the exact same code into either vim or nano running within the same terminal works fine. So I believe that this may be a bug in R itself. It's easy to work around by disabling bracketed paste in the terminal, but it would be great if this could actually be made to work, especially given that bracketed paste is the default on my desktop environment.

If given an account, I would be happy to file this as a bug; let me know if that is desired. In the meantime, have others run into this and perhaps identified the root cause and/or a different workaround?

Thanks,
Cesko

sessionInfo():

R version 4.1.0 (2021-05-18)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Arch Linux

Matrix products: default
BLAS/LAPACK: /opt/intel/mkl/lib/intel64/libmkl_gf_lp64.so

locale:
 [1] LC_CTYPE=nl_NL.UTF-8       LC_NUMERIC=C              
 [3] LC_TIME=nl_NL.UTF-8        LC_COLLATE=nl_NL.UTF-8    
 [5] LC_MONETARY=nl_NL.UTF-8    LC_MESSAGES=nl_NL.UTF-8   
 [7] LC_PAPER=nl_NL.UTF-8       LC_NAME=C                 
 [9] LC_ADDRESS=C               LC_TELEPHONE=C            
[11] LC_MEASUREMENT=nl_NL.UTF-8 LC_IDENTIFICATION=C       

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

loaded via a namespace (and not attached):
[1] compiler_4.1.0  Matrix_1.3-4    mgcv_1.8-36     splines_4.1.0  
[5] nlme_3.1-152    grid_4.1.0      lattice_0.20-44