Running 'testthat-class.R' [3s/3s]
  Running 'testthat-exe1.R' [2s/3s]
  Running 'testthat-exe2.R' [2s/3s]
  Running 'testthat-exe3.R' [2s/3s]
  Running 'testthat-nldoc.R' [4s/35s]
  Running 'testthat-simul.R' [4s/5s]
  Running 'testthat-util.R' [3s/4s]
Running the tests in 'tests/testthat-nldoc.R' failed.
Complete output:
  > Sys.unsetenv("R_TESTS")
  > 
  > library(testthat)
  > library(nlrx)
  > 
  > test_check("nlrx", filter = "nldoc")
  /usr/bin/pandoc +RTS -K512m -RTS nldoc.utf8.md --to html4 --from markdown+autolink_bare_uris+tex_math_single_backslash+smart --output nldoc.html --email-obfuscation none --self-contained --standalone --section-divs --table-of-contents --toc-depth 3 --template /home/hornik/tmp/R.check/r-devel-clang/Work/build/Packages/rmarkdown/rmd/h/default.html --no-highlight --variable highlightjs=1 --number-sections --variable 'theme:cosmo' --include-in-header /tmp/RtmpnMH6PB/rmarkdown-str6043795f7310.html --mathjax --variable 'mathjax-url:https://mathjax.rstudio.com/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML' --lua-filter /home/hornik/tmp/R.check/r-devel-clang/Work/build/Packages/rmarkdown/rmd/lua/pagebreak.lua --lua-filter /home/hornik/tmp/R.check/r-devel-clang/Work/build/Packages/rmarkdown/rmd/lua/latex-div.lua 
  Could not fetch http://ccl.northwestern.edu/images/creativecommons/byncsa.png
  HttpExceptionRequest Request {
    host                 = "ccl.northwestern.edu"
    port                 = 80
    secure               = False
    requestHeaders       = []
    path                 = "/images/creativecommons/byncsa.png"
    queryString          = ""
    method               = "GET"
    proxy                = Nothing
    rawBody              = False
    redirectCount        = 10
    responseTimeout      = ResponseTimeoutDefault
    requestVersion       = HTTP/1.1
  }
   ResponseTimeout
  -- 1. Error: nldoc (@test-nldoc.R#14)  -----------------------------------------
  pandoc document conversion failed with error 61
  Backtrace:
   1. nlrx::nldoc(...)
   2. nlrx:::nldoc_write_nldoc(...)
   3. rmarkdown::render(mdfile)
   4. rmarkdown:::convert(output_file, run_citeproc)
   5. rmarkdown::pandoc_convert(...)
  
  == testthat results  ===========================================================
  [ OK: 0 | SKIPPED: 0 | WARNINGS: 0 | FAILED: 1 ]
  1. Error: nldoc (@test-nldoc.R#14) 
  
  Error: testthat unit tests failed
  In addition: Warning message:
  In extract_lang(f = comp_lang, y = quote(if (.isMethodsDispatchOn() &&  :
    devtools is incompatible with the current version of R. `load_all()` may function incorrectly.
  Execution halted