test.data.table(): count skipped message tests

When working in foreign mode, count the occurrences of tests for message
content (which are essentially skipped) and report the number if it's
non-zero.

Author: aitap

R/test.data.table.R

@@ -130,6 +130,7 @@ test.data.table = function(script="tests.Rraw", verbose=FALSE, pkg=".", silent=F
   }
   assign("foreign", foreign, envir=env)
   assign("nfail", 0L, envir=env)
+  assign("nskip", 0L, envir=env)
   assign("ntest", 0L, envir=env)
   assign("prevtest", -1L, envir=env)
   assign("whichfail", NULL, envir=env)
@@ -282,6 +283,7 @@ test.data.table = function(script="tests.Rraw", verbose=FALSE, pkg=".", silent=F
 
   nfail = env$nfail
   ntest = env$ntest
+  nskip = env$nskip
   if (nfail > 0L) {
     # nocov start
     stopf(
@@ -331,6 +333,7 @@ test.data.table = function(script="tests.Rraw", verbose=FALSE, pkg=".", silent=F
     get("mtext")(lastRSS, side=4L, at=lastRSS, las=1L, font=2L)
   }
 
+  if (foreign && nskip > 0L) catf("Skipped %d tests for translated messages. ", nskip) # nocov
   catf("All %d tests (last %.8g) in %s completed ok in %s\n", ntest, env$prevtest, names(fn), timetaken(env$started.at))
   ans = nfail==0L
   attr(ans, "timings") = timings  # as attr to not upset callers who expect a TRUE/FALSE result
@@ -409,6 +412,7 @@ test = function(num,x,y=TRUE,error=NULL,warning=NULL,message=NULL,output=NULL,no
     memtest.id = get("memtest.id", parent.frame())
     filename = get("filename", parent.frame())
     foreign = get("foreign", parent.frame())
+    nskip = get("nskip", parent.frame())
     showProgress = get("showProgress", parent.frame())
     time = nTest = RSS = NULL  # to avoid 'no visible binding' note
     # TODO(R>=4.0.2): Use add=TRUE up-front in on.exit() once non-positional arguments are supported.
@@ -451,6 +455,11 @@ test = function(num,x,y=TRUE,error=NULL,warning=NULL,message=NULL,output=NULL,no
     length(grep(x, y, fixed=TRUE)) ||  # try treating x as literal first; useful for most messages containing ()[]+ characters
     length(tryCatch(grep(x, y, ignore.case=ignore.case), error=function(e)NULL))  # otherwise try x as regexp
   }
+  if (foreign && .test.data.table && (
+    length(error) || length(warning) || length(message) || length(output) ||
+    length(notOutput) || length(ignore.warning)
+  ))
+    assign("nskip", nskip+1L, parent.frame(), inherits=TRUE) # nocov
 
   xsub = substitute(x)
   ysub = substitute(y)