pkg <- "fOptions"

if(require("RUnit", quietly = TRUE)) 
{

    library(package=pkg, character.only = TRUE)
    if(!(exists("path") && file.exists(path)))
        path <- system.file("unitTests", package = pkg)

    ## --- Testing ---

    ## Define tests
    testSuite <- defineTestSuite(name = paste(pkg, "unit testing"), 
        dirs = path)

    if(interactive()) {
        cat("Now have RUnit Test Suite 'testSuite' for package '", 
            pkg, "' :\n", sep='')
        str(testSuite)
        cat('', "Consider doing",
            "\t  tests <- runTestSuite(testSuite)", "\nand later",
            "\t  printTextProtocol(tests)", '', sep = "\n")
    } else { 
        ## run from shell / Rscript / R CMD Batch / ...
        ## Run
        tests <- runTestSuite(testSuite)

        if(file.access(path, 02) != 0) {
            ## cannot write to path -> use writable one
            tdir <- tempfile(paste(pkg, "unitTests", sep="_"))
            dir.create(tdir)
            pathReport <- file.path(tdir, "report")
            cat("RUnit reports are written into ", tdir, "/report.(txt|html)",
                sep = "")
        } else {
            pathReport <- file.path(path, "report")
        }

        ## Print Results:
        printTextProtocol(tests)
        printTextProtocol(tests, 
            fileName = paste(pathReport, ".txt", sep = ""))
        
        ## Print HTML Version to a File:
        printHTMLProtocol(tests, 
            fileName = paste(pathReport, ".html", sep = ""))

        ## stop() if there are any failures i.e. FALSE to unit test.
        ## This will cause R CMD check to return error and stop
        if(getErrors(tests)$nFail > 0) {
            stop("one of the unit tests failed")
        }
    }
} else {
    cat("R package 'RUnit' cannot be loaded -- no unit tests run\n",
    "for package", pkg,"\n")
}