Enforce safeguards when moving files

NEWS

@@ -11,6 +11,8 @@ o Changed clean() so user can specify directories to remove.
 
 o Changed write.taf() to search in the global workspace if 'x' is a string.
 
+o Changed cp() to enforce safeguards when moving files.
+
 
 
 
@@ -29,7 +31,7 @@ o Changed read.taf() and write.taf() so they can read/write many tables in one
 
 o Changed write.taf() so the name of the data frame is the default filename.
 
-o Changed cp() so it preserves the timestamp when copying a file.
+o Changed cp() to preserve the timestamp when copying a file.
 
 
 
@@ -61,7 +63,7 @@ o Added arguments 'include' and 'engine' to make().
 
 o Added argument 'local' to sourceTAF(), replacing the 'rm' argument.
 
-o Changed sourceAll() so it only runs TAF scripts: data.R, input.R, model.R,
+o Changed sourceAll() to only run TAF scripts: data.R, input.R, model.R,
   output.R, and report.R.
 
 

R/cp.R

@@ -9,10 +9,24 @@
 #'
 #' @return \code{TRUE} for success, \code{FALSE} for failure, invisibly.
 #'
+#' @note
+#' To prevent accidental loss of files, two safeguards are enforced when
+#' \code{move = TRUE}:
+#' \enumerate{
+#' \item When moving files, the \code{to} argument must either have a filename
+#' extension or be an existing directory.
+#' \item When moving many files to one destination, the \code{to} argument must
+#' be an existing directory.
+#' }
+#' If these conditions do not hold, no files are changed and an error is
+#' returned.
+#'
 #' @seealso
 #' \code{\link{file.copy}} and \code{\link{unlink}} are the underlying functions
 #' used to copy and (if \code{move = TRUE}) delete files.
 #'
+#' \code{\link{file.rename}} is the base function to rename files.
+#'
 #' \code{\link{icesTAF-package}} gives an overview of the package.
 #'
 #' @examples
@@ -27,6 +41,8 @@
 #' cp("datasets/*", "everything")
 #' }
 #'
+#' @importFrom tools file_ext
+#'
 #' @export
 
 cp <- function(from, to, move=FALSE)
@@ -35,6 +51,16 @@ cp <- function(from, to, move=FALSE)
   ## in case some filenames without asterisk are not found
   from <- sort(unique(c(Sys.glob(from), from[!grepl("\\*", from)])))
 
+  if(move)
+  {
+    ## Safeguard 1: destination must have file_ext or exist as dir
+    if(any(file_ext(to)=="" & !dir.exists(to)))
+      stop("when moving, 'to' must have file extension or exist as directory")
+    ## Safeguard 2: many-one, dir must exist
+    if(length(from)>1 && length(to)==1 && !dir.exists(to))
+      stop("when moving many -> one, 'to' must be an existing directory")
+  }
+
   out <- mapply(file.copy, from, to, overwrite=TRUE,
                 recursive=dir.exists(from), copy.date=TRUE)
   if(move)