Merge pull request #6881 from Rdatatable/R.utils_tests

add skips for tests needing R.utils

Author: MichaelChirico

inst/tests/tests.Rraw

@@ -10029,7 +10029,7 @@ if (!haszlib()) {
   test(1658.441, file.info(f3)$size, file.info(f1)$size)
   test(1658.442, file.info(f4)$size >= file.info(f1)$size)
   test(1658.443, file.info(f1)$size >= file.info(f5)$size)
-  test(1658.444, fread(f6, col.names = c("a", "b")), DT)
+  if (test_R.utils) test(1658.444, fread(f6, col.names = c("a", "b")), DT)
   unlink(c(f1,f2,f3,f4,f5,f6))
 }
 DT = data.table(a=1:3, b=list(1:4, c(3.14, 100e10), c("foo", "bar", "baz")))
@@ -21044,7 +21044,7 @@ test(2304.099, copy(DT)[2L, let(L1=list(NULL), L2=list(NULL))], ans)
 test(2304.100, set(copy(DT), i=2L, j=c("L1", "L2"), value=list(list(NULL), list(NULL))), ans)
 
 # the integer overflow in #6729 is only noticeable with UBSan
-test(2305, { fread(testDir("issue_6729.txt.bz2")); TRUE })
+if (test_R.utils) test(2305, { fread(testDir("issue_6729.txt.bz2")); TRUE })
 
 if (exists("sort_by", "package:base")) {
   # sort_by.data.table