Arvados

h1. Emacs and Go

With this stuff in ~/.emacs, you should get the following features:

* (not really a feature) a strange delay the first time you open a Go file, while a bunch of dev tools get installed into GOPATH

* With point on an identifier, @M-.@ jumps to the identifier's definition (@M-*@ returns to original point)

* Gofmt and goimports get applied automatically when saving

* Requires "gocode":https://github.com/nsf/gocode "goimports":https://godoc.org/golang.org/x/tools/cmd/goimports and "godef":https://godoc.org/github.com/rogpeppe/godef

<pre><code class="lisp">

(setq-default indent-tabs-mode nil)

(require 'package)

(add-to-list 'package-archives

             '("melpa" . "https://melpa.org/packages/"))

(add-to-list 'package-archives

             '("melpa-stable" . "https://stable.melpa.org/packages/") t)

(when (< emacs-major-version 24)

  ;; compatibility libraries like cl-lib                                                                                                                                                                                        

  (add-to-list 'package-archives '("gnu" . "http://elpa.gnu.org/packages/")))

(add-to-list 'package-archives

             '("melpa" . "http://melpa.milkbox.net/packages/") t)

(package-initialize)

(define-key global-map (kbd "RET") 'newline-and-indent)

(setq package-list '(async auto-complete dash

  go-add-tags go-autocomplete go-errcheck go-mode go-playground

  go-rename gotest markdown-mode

  yaml-mode))

(dolist (package package-list)

  (unless (package-installed-p package)

    (message "installing %s..." package)

    (package-install package)))

(defun arvados-gopath ()

  (let ((bfn (buffer-file-name)))

    (setenv "GOPATH"

            (with-temp-buffer

              (call-process "bash" nil t nil "-c"

                            "gp=${GOPATH:-${HOME}/go}; d=${0}; while [[ ${d} != '' ]]; do if [[ -e ${d}/services/keep-web/. ]]; then gp=${d}/tmp/GOPATH; mkdir -p ${gp}/src/git.arvados.org; ln -sfn ${d} ${gp}/src/git.arvados.org/arvados.git; break; fi; d=${d%/*}; done; mkdir -p ${gp}; echo -n ${gp}"

                            bfn)

              (buffer-substring (point-min) (point-max))))))

(defun go-mode-omnibus ()

  (let ((gopath (arvados-gopath)))

    (make-local-variable 'process-environment)

    (make-local-variable 'exec-path)

    (add-to-list 'exec-path (concat gopath "/bin"))

    (with-temp-buffer

      (call-process "bash" nil t t "-c" "([[ -x ${1}/bin/gocode ]] && ${1}/bin/goimports -srcdir / /dev/null) || go get -u -v golang.org/x/tools/cmd/... github.com/rogpeppe/godef github.com/nsf/gocode" "-" gopath))

    (auto-complete-mode 1)

                                        ; call gofmt before saving                                                                                                                                                              

    (add-hook 'before-save-hook 'gofmt-before-save)

    (setq gofmt-command "goimports")

                                        ; compile with go                                                                                                                                                                       

    (if (not (string-match "go" compile-command))

        (set (make-local-variable 'compile-command)

             "go build -v && go test -v && go vet"))

                                        ; godef-jump key bindings                                                                                                                                                               

    (local-set-key (kbd "M-.") 'godef-jump)

    (local-set-key (kbd "M-*") 'pop-tag-mark)))

(add-hook 'go-mode-hook 'go-mode-omnibus)

</code></pre>