Creates list of paths by file extension & checks they exist

Ext or prefix can be a vector or single character. The shorter value will be propagated across all values of the other. See Examples for details.

cmd_file_expect(prefix, ext, outdir = ".")

Arguments

prefix	name of file prefix for each extension.
ext	vector of file extensions
outdir	directory the files will be inside

Value

vector of valid file paths

Details

If files are not found, throws an error

Examples

if (FALSE) {
# Expects many file types of same prefix
# ie myFile.txt, myFile.html, myFile.xml
cmd_file_expect("myFile", c("txt", "html", "xml"))

# Expects many files of same type
# ie myFile1.txt, myFile2.txt, myFile3.txt
cmd_file_expect(c("myFile1", "myFile2", "myFile3"), "txt")

# Expects many files with each prefix and each extension
# ie myFile1.txt, myFile1.html, myFile2.txt, myFile2.html
cmd_file_expect(c("myFile1", "myFile2"), c("txt", "html"))

}