Error(s) in re-building vignettes:
  ...
--- re-building ‘ggrepel.Rmd’ using rmarkdown
 ----------- FAILURE REPORT -------------- 
 --- failure: the condition has length > 1 ---
 --- srcref --- 
: 
 --- package (from environment) --- 
ggrepel
 --- call from context --- 
to_unit(box.padding)
 --- call from argument --- 
if (class(x) == "unit") {
    return(x)
}
 --- R stacktrace ---
where 1: to_unit(box.padding)
where 2: gTree(limits = limits, data = data, lab = lab, nudges = nudges, 
    box.padding = to_unit(box.padding), point.padding = to_unit(point.padding), 
    segment.colour = segment.colour, segment.size = segment.size, 
    segment.alpha = segment.alpha, min.segment.length = to_unit(min.segment.length), 
    arrow = arrow, force = force, max.iter = max.iter, direction = direction, 
    seed = seed, cl = "textrepeltree")
where 3: grobName(grob, prefix)
where 4: ggname("geom_text_repel", gTree(limits = limits, data = data, 
    lab = lab, nudges = nudges, box.padding = to_unit(box.padding), 
    point.padding = to_unit(point.padding), segment.colour = segment.colour, 
    segment.size = segment.size, segment.alpha = segment.alpha, 
    min.segment.length = to_unit(min.segment.length), arrow = arrow, 
    force = force, max.iter = max.iter, direction = direction, 
    seed = seed, cl = "textrepeltree"))
where 5: f(...)
where 6: (function (...) 
f(...))(data, panel_params, coord, parse = FALSE, na.rm = FALSE, 
    box.padding = 0.25, point.padding = 1e-06, segment.colour = NULL, 
    segment.size = 0.5, segment.alpha = NULL, min.segment.length = 0.5, 
    arrow = NULL, force = 1, max.iter = 2000, nudge_x = 0, nudge_y = 0, 
    xlim = c(NA, NA), ylim = c(NA, NA), direction = "both", seed = NA)
where 7: do.call(self$draw_panel, args)
where 8: FUN(X[[i]], ...)
where 9: lapply(split(data, data$PANEL), function(data) {
    if (empty(data)) 
        return(zeroGrob())
    panel_params <- layout$panel_params[[data$PANEL[1]]]
    do.call(self$draw_panel, args)
})
where 10: f(..., self = self)
where 11: self$geom$draw_layer(data, self$geom_params, layout, layout$coord)
where 12: f(..., self = self)
where 13: l$draw_geom(d, layout)
where 14: (function (l, d) 
l$draw_geom(d, layout))(dots[[1L]][[2L]], dots[[2L]][[2L]])
where 15: mapply(FUN = f, ..., SIMPLIFY = FALSE)
where 16: Map(function(l, d) l$draw_geom(d, layout), plot$layers, data)
where 17: ggplot_gtable.ggplot_built(ggplot_build(x))
where 18: ggplot_gtable(ggplot_build(x))
where 19: FUN(X[[i]], ...)
where 20: lapply(grobs[toconv], ggplot2::ggplotGrob)
where 21: arrangeGrob(...)
where 22: gridExtra::grid.arrange(p1, p2, ncol = 2)
where 23: eval(expr, envir, enclos)
where 24: eval(expr, envir, enclos)
where 25: withVisible(eval(expr, envir, enclos))
where 26: withCallingHandlers(withVisible(eval(expr, envir, enclos)), warning = wHandler, 
    error = eHandler, message = mHandler)
where 27: handle(ev <- withCallingHandlers(withVisible(eval(expr, envir, 
    enclos)), warning = wHandler, error = eHandler, message = mHandler))
where 28: timing_fn(handle(ev <- withCallingHandlers(withVisible(eval(expr, 
    envir, enclos)), warning = wHandler, error = eHandler, message = mHandler)))
where 29: evaluate_call(expr, parsed$src[[i]], envir = envir, enclos = enclos, 
    debug = debug, last = i == length(out), use_try = stop_on_error != 
        2L, keep_warning = keep_warning, keep_message = keep_message, 
    output_handler = output_handler, include_timing = include_timing)
where 30: evaluate::evaluate(...)
where 31: evaluate(code, envir = env, new_device = FALSE, keep_warning = !isFALSE(options$warning), 
    keep_message = !isFALSE(options$message), stop_on_error = if (options$error && 
        options$include) 0L else 2L, output_handler = knit_handlers(options$render, 
        options))
where 32: in_dir(input_dir(), evaluate(code, envir = env, new_device = FALSE, 
    keep_warning = !isFALSE(options$warning), keep_message = !isFALSE(options$message), 
    stop_on_error = if (options$error && options$include) 0L else 2L, 
    output_handler = knit_handlers(options$render, options)))
where 33: block_exec(params)
where 34: call_block(x)
where 35: process_group.block(group)
where 36: process_group(group)
where 37: withCallingHandlers(if (tangle) process_tangle(group) else process_group(group), 
    error = function(e) {
        setwd(wd)
        cat(res, sep = "\n", file = output %n% "")
        message("Quitting from lines ", paste(current_lines(i), 
            collapse = "-"), " (", knit_concord$get("infile"), 
            ") ")
    })
where 38: process_file(text, output)
where 39: knitr::knit(knit_input, knit_output, envir = envir, quiet = quiet)
where 40: rmarkdown::render(file, encoding = encoding, quiet = quiet, envir = globalenv(), 
    output_dir = getwd(), ...)
where 41: vweave_rmarkdown(...)
where 42: engine$weave(file, quiet = quiet, encoding = enc)
where 43: doTryCatch(return(expr), name, parentenv, handler)
where 44: tryCatchOne(expr, names, parentenv, handlers[[1L]])
where 45: tryCatchList(expr, classes, parentenv, handlers)
where 46: tryCatch({
    engine$weave(file, quiet = quiet, encoding = enc)
    setwd(startdir)
    output <- find_vignette_product(name, by = "weave", engine = engine)
    if (!have.makefile && vignette_is_tex(output)) {
        texi2pdf(file = output, clean = FALSE, quiet = quiet)
        output <- find_vignette_product(name, by = "texi2pdf", 
            engine = engine)
    }
    outputs <- c(outputs, output)
}, error = function(e) {
    thisOK <<- FALSE
    fails <<- c(fails, file)
    message(gettextf("Error: processing vignette '%s' failed with diagnostics:\n%s", 
        file, conditionMessage(e)))
})
where 47: tools:::buildVignettes(dir = "/home/hornik/tmp/R.check/r-devel-gcc/Work/PKGS/ggrepel.Rcheck/vign_test/ggrepel", 
    ser_elibs = "/home/hornik/tmp/scratch/Rtmpd9yDtP/file139c5c2b99a1.rds")

 --- value of length: 3 type: logical ---
[1] FALSE  TRUE FALSE
 --- function from context --- 
function (x) 
{
    if (class(x) == "unit") {
        return(x)
    }
    if (is.na(x)) {
        return(NA)
    }
    unit(x, "lines")
}
<bytecode: 0x55f0db27e9c8>
<environment: namespace:ggrepel>
 --- function search by body ---
Function to_unit in namespace ggrepel has this body.
 ----------- END OF FAILURE REPORT -------------- 
Quitting from lines 63-77 (ggrepel.Rmd) 
Error: processing vignette 'ggrepel.Rmd' failed with diagnostics:
the condition has length > 1
--- failed re-building ‘ggrepel.Rmd’

SUMMARY: processing the following file failed:
  ‘ggrepel.Rmd’

Error: Vignette re-building failed.
Execution halted