cider-repl-clear-buffer stops working

[dagda1]

My projects.clj looks like this:

{:user {
        :dependencies [[com.cemerick/piggieback "0.2.1"]
                       [org.clojure/tools.nrepl "0.2.10"]]
        :plugins [[cider/cider-nrepl "0.10.0-SNAPSHOT"]]
        }}

I'm pretty new to clojure and cider but when I have the code in one window and cider-repl running in the other, it is nice to be able to clear the repl buffer with C-c M-o but C-c M-o stops working after I have executed it once and the buffer has been cleared.

If I select cider-repl-clear-buffer from M-x I can see the error message:

Wrong type argument: integer-or-marker-p nil

The following stack trace in the *Messages* buffer

Loading /Users/paulcowan/projects/scratch/src/scratch/core.clj...
=> nil
Loading /Users/paulcowan/projects/scratch/src/scratch/core.clj...
=> nil
Quit
call-interactively: Wrong type argument: integer-or-marker-p, nil
user-error: Minibuffer window is not active
call-interactively: Wrong type argument: integer-or-marker-p, nil
Auto-saving...done
call-interactively: Wrong type argument: integer-or-marker-p, nilInvalid face attribute :foreground nil
Invalid face attribute :foreground nil [117 times]

So all I do is

1. cider-jack-in
2. Write some code and C-c C-k to execute it.
3. C-c M-o and the buffer clears
4. Write some code and C-c C-k to execute it.
5. hit C-c M-o again and cider-repl-clear-buffer no longer works.

If nobody else is experiencing this error, I wonder if my workflow of using C-c C-k is normal?

[Malabarba]

Do M-x toggle-debug-on-error, and then reproduce this error.
You'll get a proper backtrace which you can paste here to give us more information.

[dagda1]

Here is the backtrace:

Debugger entered--Lisp error: (wrong-type-argument integer-or-marker-p nil)
cider-repl-clear-buffer()
call-interactively(cider-repl-clear-buffer record nil)
command-execute(cider-repl-clear-buffer record)
execute-extended-command(nil "cider-repl-clear-buffer")
smex-read-and-run(("toggle-debug-on-error" "cider-repl-clear-buffer" "cider-jack-in" "list-packages" "magit-status" "ag-project" "enable-paredit-mode" "paredit-mode" "blink-cursor-mode" "global-company-mode" "ag-kill-buffers" "disable-paredit-mode" "kill-other-buffers" "load-file" "kill-some-buffers" "cider-quit" "package-install" "auto-save-mode" "eval-buffer" "cider-restart" "cider-version" "visit-tags-table" "magit-process-kill" "sdb" "ag-mode" "find-library" "minitest-mode" "revert-buffer" "ag/kill-process" "cider-interrupt" "elm-indent-mode" "erc-notify-mode" "ag-project-dired" "cider-repl-kill-input" "package-list-packages" "projectile-invalidate-cache" "cider-repl-toggle-pretty-printing" "org-table-toggle-formula-debugger" "cider-clear-compilation-highlights" "ag" "cd" "5x5" "arp" "dbx" "dig" "erc" "ert" "eww" "ftp" "gdb" ...))
smex()
call-interactively(smex nil nil)
command-execute(smex)

[bbatsov]

If nobody else is experiencing this error, I wonder if my workflow of using C-c C-k is normal?

Yeah, that's OK. Personally, I don't use C-c C-k that often - usually I just re-evaluate the code I've actually changed. What's your cider version info?

[dagda1]

@bbatsov here is my version info:

; CIDER 0.10.0snapshot (package: 20150801.627) (Java 1.7.0_45, Clojure 1.6.0, nREPL 0.2.10)

Do you think it would be possible, if you could describe your workflow in a few words?

I think that would be very beneficial to me.

[Malabarba]

My workflow is to just reload code I just changed by hitting C-M-x on it. But there's nothing wrong with using C-c C-k, a lot of people do that and I'm sure one of them would have noticed your issue.

It's clear that one of the repl markers is being set to nil for you, even though all of them should always be valid markers.

1. Do you have anything in cider-repl-clear-buffer-hook?
2. When you get this problem, which of the following vars is nil for you: cider-repl-prompt-start-mark, cider-repl-output-start, cider-repl-output-end, or cider-repl-input-start-mark?

[dagda1]

Is cider-repl-clear-buffer-hook a command? I don't have it available through M-x.

[Malabarba]

No, it's a variable. Try to see it with C-h v. If you don't get anything, that's normal.

[dagda1]

So when I run c-h v for cider-repl-prompt-start-mark I get:

cider-repl-prompt-start-mark is a variable defined in `cider-repl.el'.
Its value is nil

  Automatically becomes buffer-local when set.

for cider-repl-output-start

cider-repl-output-start is a variable defined in `cider-repl.el'.
Its value is nil

  Automatically becomes buffer-local when set.

The same is true for cider-repl-output-end and cider-repl-input-start-mark.

[Malabarba]

Did you do that inside the repl buffer?

[dagda1]

Ah right, my bad,

Here are the variables in the buffer.

cider-repl-prompt-start-mark outputs

cider-repl-prompt-start-mark is a variable defined in `cider-repl.el'.
Its value is #<marker at 93 in *cider-repl scratch*>
Local in buffer *cider-repl scratch*; global value is nil

  Automatically becomes buffer-local when set.

cider-repl-output-start outputs:

cider-repl-output-start is a variable defined in `cider-repl.el'.
Its value is #<marker at 92 in *cider-repl scratch*>
Local in buffer *cider-repl scratch*; global value is nil

  Automatically becomes buffer-local when set.

cider-repl-output-end outputs

cider-repl-output-end is a variable defined in `cider-repl.el'.
Its value is #<marker at 92 in *cider-repl scratch*>
Local in buffer *cider-repl scratch*; global value is nil

cider-repl-input-start-mark outputs

cider-repl-input-start-mark is a variable defined in `cider-repl.el'.
Its value is #<marker at 99 in *cider-repl scratch*>
Local in buffer *cider-repl scratch*; global value is nil

  Automatically becomes buffer-local when set.

cider-repl-clear-buffer-hook gives no match.

[Malabarba]

Ok, one more question. :) Is that after reproducing the problem?

[dagda1]

I've captured the variables again after the problem:

cider-repl-prompt-start-mark outputs

cider-repl-prompt-start-mark is a variable defined in `cider-repl.el'.
Its value is #<marker at 1 in *cider-repl scratch*>
Local in buffer *cider-repl scratch*; global value is nil

  Automatically becomes buffer-local when set.

cider-repl-output-start outputs:

cider-repl-output-start is a variable defined in `cider-repl.el'.
Its value is #<marker at 1 in *cider-repl scratch*>
Local in buffer *cider-repl scratch*; global value is nil

  Automatically becomes buffer-local when set.

cider-repl-output-end outputs

cider-repl-output-end is a variable defined in `cider-repl.el'.
Its value is #<marker at 1 in *cider-repl scratch*>
Local in buffer *cider-repl scratch*; global value is nil

cider-repl-input-start-mark outputs

cider-repl-input-start-mark is a variable defined in `cider-repl.el'.
Its value is #<marker at 255 in *cider-repl scratch*>
Local in buffer *cider-repl scratch*; global value is nil

cider-repl-clear-buffer-hook gives no match.

[Malabarba]

Alright. Then I think it's safe to say that I am clueless. :)

[dagda1]

Same thing happens even if I use C-M x.

cider-repl-clear-buffer is not a happy bunny for me anyway after the first execution irrespective of what proceeds it.

[expez]

@dagda1 you might have to dig into edebug to debug this function yourself. Learning edebug takes around 5 minutes--it's incredibly easy to use--and it's well worth the trouble imo.