Add post-command-hook related tests

[geraldus]

Don't merge yet, I opened this to see coverage stats first.

@gracjan I've spent few hour trying to make it record changes to flag during ert running test. I have tried command-execute, call-interactively, execute-kbd-macro, and changing modes but flag remains empty all the time. Can you help me with this?

[gracjan]

Use:

      (execute-kbd-macro "DEF")

[geraldus]

This gives error during test:

(end-of-buffer)

(goto-char (point-min)) does not help.

[gracjan]

Summary:

• insert does not execute post command hooks, but execute-kbd-macro does
• a temporary switch-to-buffer is needed for execute-kbd-macro to work correctly
• there are nice functional functions in cl-lib.el

[geraldus]

Well, I've found only two ways to cover haskell-utils-async-update-post-command-flag — to call it directly or explicitly run post-command hooks (run-hooks 'post-command-hook). The former is just a coverage hack and in fact tests nothing, while latter looks good. I guess post-command hooks wont't run until test body is not fully evaluated (there is only one command stored in flag-variable — ert). This method also work with with-temp-buffer.

[geraldus]

Don't merge this yet. Let's merge test-utils first, then I'll rebase code (I guess this will be needed, won't it?).

[geraldus]

Ok, this is almost total coverage! 📈

Any good ideas about last uncovered function?

[gracjan]

Use with-temp-switch-to-buffer in place of with-temp-buffer and then use execute-kbd-macro in place of (run-hooks 'post-command-hook). It will work correctly.

[geraldus]

Well, we cannot test interactive stuff in batch mode, because:

Part of batch mode is that it does not have interactivity ...

An important caveat to this approach is that it will not work in a batch-mode emacs session, presumably because emacs doesn't process keyboard input at all in batch mode.

So, I'll remove last commit in few minutes, @gracjan can we have some special init file to run Emacs not in batch mode (if this is even possible on Travis), then run interactive tests with mentioned hacks [1] and finally exit Emacs?
By the way, can't contact you via IRC whole day, you're constantly online, does this mean that you receives all messages I sent you?

[gracjan]

@geraldus: I never saw your interactive commit so I do not know what you are talking about.

I have some IRC bouncer set up, so I get all messages when I get back to computer.

[geraldus]

@gracjan wow, Evil's registers prevented me from loosing it comletely:

(ert-deftest read-directory-name ()
  "Test `haskell-utils-read-directory-name'.
This is very simple test, it just runs
  `haskell-utils-read-directory-name' function with default
  directory set to home dir.  Since we have no clue about
  evnironment the only way to test this function will be simulate
  RET keypress and compare result to home folder path - the
  latter should be a prexif ot former."
  (let* ((home (getenv "HOME"))
         (unread-command-events (listify-key-sequence (kbd "RET G-g")))
         (result (haskell-utils-read-directory-name "> " home)))
    (should (string-prefix-p home result))))

while this woks fine in non-batch mode, Travis builds are failing after 10 minutes timeout.

[gracjan]

In the particular case of haskell-utils-read-directory-name it is better to use el-mock to mock read-directory-name. We have el-mock dependency already so this is good.

[geraldus]

@gracjan I didn't catch how to use it, can you explain a bit?

[gracjan]

Example of el-mock usage:

    (mocklet (((haskell-session-name "dummy-session") => "dumses1"))
                     (haskell-process-compute-process-log-and-command "dummy-session" 'ghci)))

So in our situation this would be something like:

    (mocklet (((read-directory-name ? ? ?) => ?))
                     (should (equal "xxx" (haskell-utils-read-directory-name ? ? ?)))

[geraldus]

@gracjan let me not to be greedy in this respect and leave this final piece to you (or someone else). Sorry, I need some time to learn that mocklets and have some other tasks to do in nearest time 😔