add clipbaord support for Linux and macOS

.travis.yml

@@ -1,25 +1,27 @@
 # R for travis: see documentation at https://docs.travis-ci.com/user/languages/r
 
+# Setting up R deps
 language: r
+r: 3.2
+r_packages: covr
 cache: packages
 
+# system deps
 os:
   - linux
   - osx
+install:
+  - if [ $TRAVIS_OS_NAME = linux ]; then sudo apt-get -qq update; fi
+  - if [ $TRAVIS_OS_NAME = linux ]; then sudo apt-get install -y xclip; fi
+  - if [ $TRAVIS_OS_NAME = osx ]; then brew install xclip; fi
 
-r:
-  - 3.2
-
-r_packages:
-  - covr
-
+# postrun
 after_success:
   - Rscript -e 'covr::codecov()'
-
 notifications:
   email:
     recipients:
       - m.s.berends@umcg.nl
       - c.f.luz@umcg.nl
     on_success: change
-    on_failure: always
+    on_failure: change

R/clipboard.R

@@ -1,6 +1,6 @@
 #' Import/export from clipboard
 #'
-#' These are helper functions around \code{\link{read.table}} and \code{\link{write.table}} to import from and export to clipboard. The data will be read and written as tab-separated by default, which makes it possible to copy and paste from other software like Excel and SPSS without further transformation.
+#' These are helper functions around \code{\link{read.table}} and \code{\link{write.table}} to import from and export to clipboard, with support for Windows, Linux and macOS. The data will be read and written as tab-separated by default, which makes it possible to copy and paste from other software like Excel and SPSS without further transformation.
 #' @rdname clipboard
 #' @name clipboard
 #' @inheritParams utils::read.table
@@ -21,7 +21,16 @@ clipboard_import <- function(sep = '\t',
                              startrow = 1,
                              as_vector = TRUE) {
 
-  import_tbl <- read.delim(file = 'clipboard',
+  if (is_Windows() == TRUE) {
+    file <- 'clipboard'
+  } else {
+    # use xclip package
+    check_xclip()
+    file <- pipe("xclip -o", "r")
+    on.exit(close(file))
+  }
+  
+  import_tbl <- read.delim(file = file,
                            sep = sep,
                            header = header,
                            strip.white = TRUE,
@@ -67,9 +76,18 @@ clipboard_export <- function(x,
   
   x <- get(x)
 
+  if (is_Windows() == TRUE) {
     # set size of clipboard to 125% of the object size of x
+    file <- paste0("clipboard-", size * 1.25)
+  } else {
+    # use xclip package
+    check_xclip()
+    file <- pipe("xclip -i", "w")
+    on.exit(close(file))
+  }
+
   write.table(x = x,
-              file = paste0("clipboard-", size * 1.25),
+              file = file,
               sep = sep,
               na = na,
               row.names = FALSE,
@@ -81,3 +99,12 @@ clipboard_export <- function(x,
     cat("Successfully exported to clipboard:", NROW(x), "obs. of", NCOL(x), "variables.\n")
   }
 }
+
+is_Windows <- function() {
+  Sys.info()['sysname'] %like% "Windows"
+}
+check_xclip <- function() {
+  if (!isTRUE(file.exists(Sys.which("xclip")[1L]))) {
+      stop("Please install Linux package xclip first.")
+  }
+}

tests/testthat/test-clipboard.R

@@ -1,11 +1,9 @@
 context("clipboard.R")
 
 test_that("clipboard works", {
-  if (Sys.info()['sysname'] == "Windows") {
-    # why is the <<- needed? Won't work without it...
-    t1 <<- AMR::antibiotics
+  skip_on_os(c("linux", "solaris"))
+  t1 <<- AMR::antibiotics # why is the <<- needed? Won't work without it...
   clipboard_export(t1, info = FALSE)
   t2 <- clipboard_import()
   expect_equal(t1, t2)
-  }
 })