Merge branch 'master' into ledger-mode-automatic-transactions

Conflicts:
	lisp/ledger-init.el
	lisp/ledger-mode.el
	lisp/ledger-reconcile.el
	lisp/ledger-schedule.el

1 files changed, 101 insertions, 0 deletions

diff --git a/lisp/ledger-exec.el b/lisp/ledger-exec.el
new file mode 100644
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--- /dev/null
+++ b/lisp/ledger-exec.el
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+;;; ledger-exec.el --- Helper code for use with the "ledger" command-line tool
+
+;; Copyright (C) 2003-2013 John Wiegley (johnw AT gnu DOT org)
+
+;; This file is not part of GNU Emacs.
+
+;; This is free software; you can redistribute it and/or modify it under
+;; the terms of the GNU General Public License as published by the Free
+;; Software Foundation; either version 2, or (at your option) any later
+;; version.
+;;
+;; This is distributed in the hope that it will be useful, but WITHOUT
+;; ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+;; FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+;; for more details.
+;;
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs; see the file COPYING.  If not, write to the
+;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+;; MA 02111-1307, USA.
+
+
+;;; Commentary:
+;; Code for executing ledger synchronously.
+
+;;; Code:
+
+(defconst ledger-version-needed "3.0.0"
+  "The version of ledger executable needed for interactive features.")
+
+(defvar ledger-works nil
+  "Flag showing whether the ledger binary can support `ledger-mode' interactive features.")
+
+(defgroup ledger-exec nil
+  "Interface to the Ledger command-line accounting program."
+  :group 'ledger)
+
+(defcustom ledger-binary-path "ledger"
+  "Path to the ledger executable."
+  :type 'file
+  :group 'ledger-exec)
+
+(defun ledger-exec-handle-error (ledger-output)
+  "Deal with ledger errors contained in LEDGER-OUTPUT."
+  (with-current-buffer (get-buffer-create "*Ledger Error*")
+    (insert-buffer-substring ledger-output)
+    (view-mode)
+    (setq buffer-read-only t)))
+
+(defun ledger-exec-success-p (ledger-output-buffer)
+  (with-current-buffer ledger-output-buffer
+    (goto-char (point-min))
+    (if (and (> (buffer-size) 1) (looking-at (regexp-quote "While")))
+	nil  ;; failure, there is an error starting with "While"
+	ledger-output-buffer)))
+
+(defun ledger-exec-ledger (input-buffer &optional output-buffer &rest args)
+  "Run Ledger using INPUT-BUFFER and optionally capturing output in OUTPUT-BUFFER with ARGS."
+  (if (null ledger-binary-path)
+      (error "The variable `ledger-binary-path' has not been set")
+      (let ((buf (or input-buffer (current-buffer)))
+	    (outbuf (or output-buffer
+			(generate-new-buffer " *ledger-tmp*"))))
+	(with-current-buffer buf
+	  (let ((coding-system-for-write 'utf-8)
+		(coding-system-for-read 'utf-8))
+	    (apply #'call-process-region
+		   (append (list (point-min) (point-max)
+				 ledger-binary-path nil outbuf nil "-f" "-")
+			   args)))
+	  (if (ledger-exec-success-p outbuf)
+	      outbuf
+	      (ledger-exec-handle-error outbuf))))))
+
+(defun ledger-version-greater-p (needed)
+  "Verify the ledger binary is usable for `ledger-mode' (version greater than NEEDED)."
+  (let ((buffer ledger-buf)
+        (version-strings '()))
+    (with-temp-buffer
+      (when (ledger-exec-ledger (current-buffer) (current-buffer) "--version")
+	(goto-char (point-min))
+	(delete-horizontal-space)
+	(setq version-strings (split-string
+			       (buffer-substring-no-properties (point)
+							       (point-max))))
+	(if (and (string-match (regexp-quote "Ledger") (car version-strings))
+		 (or (string= needed (cadr version-strings))
+		     (string< needed (cadr version-strings))))
+	    t ;; success
+	    nil))))) ;;failure
+
+(defun ledger-check-version ()
+  "Verify that ledger works and is modern enough."
+  (interactive)
+  (if (setq ledger-works (ledger-version-greater-p ledger-version-needed))
+      (message "Good Ledger Version")
+      (message "Bad Ledger Version")))
+
+(provide 'ledger-exec)
+
+;;; ledger-exec.el ends here