Add test for compressLevel=1

Author: philippechataignon

inst/tests/tests.Rraw

@@ -10015,8 +10015,10 @@ if (!haszlib()) {
   test(1658.423, file.info(f1)$size < file.info(f2)$size)  # 74 < 804  (file.size() isn't available in R 3.1.0)
   if (test_R.utils) test(1658.43, fread(f1), DT)  # use fread to decompress gz (works cross-platform)
   fwrite(DT, file=f3<-tempfile(), compress="gzip")   # compress to filename not ending .gz
+  fwrite(DT, file=f4<-tempfile(), compress="gzip", compressLevel=1)   # test compressLevel
   test(1658.441, file.info(f3)$size, file.info(f1)$size)
-  unlink(c(f1,f2,f3))
+  test(1658.442, file.info(f4)$size > file.info(f1)$size, TRUE)
+  unlink(c(f1,f2,f3,f4))
 }
 DT = data.table(a=1:3, b=list(1:4, c(3.14, 100e10), c("foo", "bar", "baz")))
 test(1658.45, fwrite(DT), output=c("a,b","1,1|2|3|4","2,3.14|1e+12","3,foo|bar|baz"))