.existsTestLogger: no visible binding for global variable '.testLogger'
.silenceF : <anonymous>: no visible global function definition for
  'capture.output'
CLIArgumentParser: no visible global function definition for
  'ArgumentParser'
CLIArgumentParser: no visible global function definition for 'proto'
CLIArgumentParser : <anonymous>: no visible global function definition
  for 'capture.output'
RdSection2latex: no visible global function definition for
  'capture.output'
RdSection2latex: no visible global function definition for 'tail'
as.package: no visible global function definition for 'untar'
as.rnw: no visible global function definition for 'RweaveLatex'
checkPlot: no visible global function definition for 'png'
checkPlot: no visible global function definition for 'dev.off'
chunkOutputHook : <anonymous> : <anonymous>: no visible binding for
  global variable 'knit_hooks'
cite_pkg: no visible global function definition for 'read.bib'
extractLocalFun: no visible global function definition for
  'capture.output'
extractLocalFun: no visible global function definition for 'tail'
hook_backspace : <anonymous>: no visible binding for global variable
  'knit_hooks'
is.dir: no visible global function definition for 'file_test'
is.file: no visible global function definition for 'file_test'
isPackageInstalled : <anonymous>: no visible global function definition
  for 'compareVersion'
knit_ex: no visible global function definition for 'knit2html'
knit_ex: no visible global function definition for 'browseURL'
knit_ex: no visible global function definition for 'knit'
latex_bibliography: no visible binding for global variable 'knit_hooks'
makeUnitVignette: no visible global function definition for 'getErrors'
packageData: no visible global function definition for 'data'
packageMakefile: no visible global function definition for
  'capture.output'
parseCMD: no visible global function definition for 'capture.output'
parseCMD: no visible global function definition for 'str'
print.package_options: no visible global function definition for 'str'
qlibrary: no visible global function definition for 'capture.output'
rnw: no visible global function definition for 'par'
runVignette.rnw_knitr: no visible binding for global variable
  'opts_chunk'
runVignette.rnw_knitr: no visible global function definition for
  'knit2pdf'
runVignette.rnw_knitr: no visible global function definition for 'knit'
runVignette.rnw_sweave: no visible global function definition for
  'Sweave'
str_diff: no visible global function definition for 'head'
str_fun: no visible global function definition for 'capture.output'
str_out: no visible global function definition for 'head'
str_out: no visible global function definition for 'tail'
utestFramework: no visible global function definition for
  'capture.output'
vignetteMakefile: no visible global function definition for
  'packageDescription'
write.pkgbib: no visible global function definition for
  'installed.packages'
write.pkgbib : <anonymous>: no visible global function definition for
  'citation'
write.pkgbib: no visible global function definition for 'toBibtex'
writeUnitVignette: no visible global function definition for 'toLatex'
writeUnitVignette: no visible global function definition for
  'sessionInfo'
write_PACKAGES_index: no visible global function definition for
  'contrib.url'
write_PACKAGES_index: no visible global function definition for
  'available.packages'
write_PACKAGES_index: no visible global function definition for
  'HTMLReport'
write_PACKAGES_index : linkPackage: no visible global function
  definition for 'hwrite'
write_PACKAGES_index: no visible global function definition for
  'publish'
write_PACKAGES_index: no visible global function definition for
  'knit2html'
write_PACKAGES_index: no visible global function definition for
  'finish'
utest,RUnitTestSuite: no visible global function definition for
  'capture.output'
utest,RUnitTestSuite: no visible global function definition for
  'runTestSuite'
utest,RUnitTestSuite: no visible global function definition for
  'printTextProtocol'
utest,RUnitTestSuite: no visible global function definition for
  'printHTMLProtocol'
utest,RUnitTestSuite: no visible global function definition for
  'getErrors'
utest,character: no visible binding for global variable 'devtools'
utest,character: no visible global function definition for 'is.package'
utest,character: no visible global function definition for 'load_all'
utest,character: no visible global function definition for
  'defineTestSuite'
utest,character: no visible global function definition for 'str'
utest,character: no visible global function definition for 'test_dir'
utest,character: no visible global function definition for
  'runTestFile'
utest,character: no visible global function definition for 'test_file'
Undefined global functions or variables:
  .testLogger ArgumentParser HTMLReport RweaveLatex Sweave
  available.packages browseURL capture.output citation compareVersion
  contrib.url data defineTestSuite dev.off devtools file_test finish
  getErrors head hwrite installed.packages is.package knit knit2html
  knit2pdf knit_hooks load_all opts_chunk packageDescription par png
  printHTMLProtocol printTextProtocol proto publish read.bib
  runTestFile runTestSuite sessionInfo str tail test_dir test_file
  toBibtex toLatex untar
Consider adding
  importFrom("grDevices", "dev.off", "png")
  importFrom("graphics", "par")
  importFrom("utils", "RweaveLatex", "Sweave", "available.packages",
             "browseURL", "capture.output", "citation", "compareVersion",
             "contrib.url", "data", "file_test", "head",
             "installed.packages", "packageDescription", "sessionInfo",
             "str", "tail", "toBibtex", "toLatex", "untar")
to your NAMESPACE file.