;;; taskrunner-leiningen.el --- Provide functions to retrieve clojure tasks via lein -*- lexical-binding: t; -*-

;; Copyright (C) 2019 Yavor Konstantinov

;;;; Commentary:

;; Provide support for Leiningen(Clojure)

;;;; Code:

;;;; Requirements

(require 'cl-lib)

;;;; Variables

(defconst taskrunner-leiningen-task-section-header-regexp

"Several tasks are available:\n"

"Regexp used to match the start of the tasks output from leiningen.")

;;;; Functions

;; These are here just to silence the bytecompiler. They are defined in

;; `taskrunner.el' and will be loaded later on but due to these files being

;; required before the function being loaded, a warning is emitted.

(declare-function taskrunner--narrow-to-line "ext:taskrunner")

(declare-function taskrunner--make-task-buff-name "ext:taskrunner")

(defun taskrunner--get-leiningen-tasks-from-buffer ()

"Retrieve all leiningen tasks from the current buffer."

(let ((beg (search-forward-regexp "Several tasks are available:\n" nil t)))

(when beg

(narrow-to-region beg

(search-forward-regexp "^$"))

(cl-map 'list (lambda (elem)

(concat "LEIN" " " (car (split-string elem " "))))

(split-string (buffer-string) "\n")))))

(defun taskrunner-get-leiningen-tasks(DIR)

"Retrieve the rake tasks for the project in directory DIR.

This function returns a list of the form:

\(\"LEIN TASK1\" \"LEIN TASK2\"...)"

(let ((default-directory DIR)

;;; Store the elixir tasks retrieved

(lein-tasks))

(call-process "lein" nil (taskrunner--make-task-buff-name "leiningen") nil "-h")

(with-temp-buffer

(set-buffer (taskrunner--make-task-buff-name "leiningen"))

(goto-char (point-min))

(setq lein-tasks (taskrunner--get-leiningen-tasks-from-buffer))

(kill-current-buffer))

;;; The last line of the output of Leiningen is always \n\n This results in

;;; erronous output where the last task is of the form: "LEIN "

;;; (i.e. its blank) so it must be removed.

(butlast lein-tasks)))

(provide 'taskrunner-leiningen)

;;; taskrunner-leiningen.el ends here