在 ESS 中保存的缓冲区上运行 Rdevtool::test_that

Question

My workflow:

• Hack away at an .R or test_*.R file
• Save buffer.
• Switch to window with *R* process
• hit Cp, RET. to re-evaluate devtools::test()

To me, this seems far too arduous. Why can't I get R to run devtools::test() automatically when I save the buffer? Please help, my fingers can barely take the strain of the seven extra keystrokes!

Answer 1

This worked for a similar setup (switching to a shell buffer):

(defun devtools-test ()
  (interactive)
  (when (string-match (rx-to-string `(: ".R" eos) t) (buffer-name))
    (switch-to-buffer "*R*")
    (end-of-buffer)
    (insert "devtools::test()")
    (comint-send-input)))

(add-hook 'after-save-hook 'devtools-test)

Does that work for you?

Answer 2

For completeness, there are easier way to do this in recent versions of ESS.

The function/command ess-r-devtools-test now runs devtools::test .

So you could achieve this with (untested):

(add-hook 'ess-r-mode-hook 
          (lambda () 
             (add-hook 'after-save-hook 'devtools-test nil 'local)))

In addition, there are many other useful functions under ess-r-devtools-* for build, install etc.

It's worth noting that calling ess-r-devtools-test with the universal argument will filter tests by the current file.

So calling Cu Mx ess-r-devtools from a file my-file.R will run devtools::test(filter="my-file") .

This can be useful to bear in mind when choosing names for test files, or when rerunning only the current test file.

Answer 3

There is a ess-eval-linewise function which you can use.

Something like this (not tested):

(defun devtools-test ()
  (interactive)
  (when (and (equal ess-dialect "R")
             (string-match "^test.*\\.[Rr]$" (buffer-name)))
    (ess-eval-linewise "devtools::test()")))

(add-hook 'after-save-hook 'devtools-test)

I would not recommend this though, as for some packages tests take quite a while to run. You don't want them running on every save.

There will be a dedicated devtools functionality in ess soon. Follow this issue .