Running 'spelling.R' [0s/1s]
  Running 'testthat.R' [2s/2s]
Running the tests in 'tests/testthat.R' failed.
Complete output:
  > library(testthat)
  > library(ggdag)
  Loading required package: ggplot2
  
  Attaching package: 'ggdag'
  
  The following object is masked from 'package:ggplot2':
  
      expand_scale
  
  The following object is masked from 'package:stats':
  
      filter
  
  > 
  > test_check("ggdag")
  -- 1. Error: tidied dags are in good shape (@test_tidy_dagitty.R#4)  -----------
  unable to load shared object '/home/hornik/tmp/R.check/r-devel-clang/Work/build/Packages/V8/libs/V8.so':
    libv8.so.3.14.5: cannot open shared object file: No such file or directory
  1: dagify(y ~ x + z, x ~ z) %>% tidy_dagitty() at testthat/test_tidy_dagitty.R:4
  2: eval(lhs, parent, parent)
  3: eval(lhs, parent, parent)
  4: dagify(y ~ x + z, x ~ z)
  5: dagitty::dagitty
  6: getExportedValue(pkg, name)
  7: asNamespace(ns)
  8: getNamespace(ns)
  9: loadNamespace(name)
  10: namespaceImport(ns, loadNamespace(i, c(lib.loc, .libPaths()), versionCheck = vI[[i]]), 
         from = package)
  11: loadNamespace(i, c(lib.loc, .libPaths()), versionCheck = vI[[i]])
  12: library.dynam(lib, package, package.lib)
  13: dyn.load(file, DLLpath = DLLpath, ...)
  
  -- 2. Error: node functions produce correct columns (@test_tidy_dagitty.R#25)  -
  unable to load shared object '/home/hornik/tmp/R.check/r-devel-clang/Work/build/Packages/V8/libs/V8.so':
    libv8.so.3.14.5: cannot open shared object file: No such file or directory
  1: dagify(y ~ x + z, x ~ z) %>% tidy_dagitty() at testthat/test_tidy_dagitty.R:25
  2: eval(lhs, parent, parent)
  3: eval(lhs, parent, parent)
  4: dagify(y ~ x + z, x ~ z)
  5: dagitty::dagitty
  6: getExportedValue(pkg, name)
  7: asNamespace(ns)
  8: getNamespace(ns)
  9: loadNamespace(name)
  10: namespaceImport(ns, loadNamespace(i, c(lib.loc, .libPaths()), versionCheck = vI[[i]]), 
         from = package)
  11: loadNamespace(i, c(lib.loc, .libPaths()), versionCheck = vI[[i]])
  12: library.dynam(lib, package, package.lib)
  13: dyn.load(file, DLLpath = DLLpath, ...)
  
  == testthat results  ===========================================================
  OK: 0 SKIPPED: 0 FAILED: 2
  1. Error: tidied dags are in good shape (@test_tidy_dagitty.R#4) 
  2. Error: node functions produce correct columns (@test_tidy_dagitty.R#25) 
  
  Error: testthat unit tests failed
  Execution halted