`profvis` breaks for URL-sources, with rather mysterious error message

[fabian-s]

 source("http://www.statistik.lmu.de/~scheipl/downloads/fortprog/slow_sim.R")
 set.seed <- 232323
 observations <- 5000
 covariates <- 10
 testdata <- as.data.frame(matrix(rnorm(observations * covariates),
                                  nrow = observations))
 
library(profvis)
profvis(expr = simulate(reps = 100, seed = 20141028, data = testdata))

## Error in readChar(filename, file.info(filename)$size, useBytes = TRUE) : 
##  invalid 'nchars' argument
traceback()
##6: readChar(filename, file.info(filename)$size, useBytes = TRUE)
##5: FUN(X[[i]], ...)
##4: lapply(filenames, function(filename) {
##       if (filename == "<expr>") {
##          return(expr_source)
##       }
##       filehandle <- tryCatch(file(filename, "rb"), error = function(e) NULL, 
##           warning = function(e) NULL)
##       if (is.null(filehandle)) {
##           return(extract_source_from_srcref(filename, srcref_cache))
##       }
##       on.exit(close(filehandle))
##       readChar(filename, file.info(filename)$size, useBytes = TRUE)
##   })
##3: get_file_contents(filenames, expr_source)
##2: parse_rprof(prof_output, expr_source)
##1: profvis(expr = simulate(reps = 100, seed = 20141028, data = testdata))

Issue is that file.info(file) only returns list of NAs if file is an URL.

[wch]

Thanks for the report! It should be fixed now.

[wch]

That is, it won't error, and won't try to load the remote sources.

[fabian-s]

Man, you're too fast -- I just wanted to send you a pull request with a similar patch...

You guys are amazing, thanks for all the great packages and the awesome support!