Going forward defun should go to end of defun

haskell-decl-scan.el

@@ -2,6 +2,7 @@
 
 ;; Copyright (C) 2004, 2005, 2007, 2009  Free Software Foundation, Inc.
 ;; Copyright (C) 1997-1998  Graeme E Moss
+;; Copyright (C) 2016  Chris Gregory
 
 ;; Author: 1997-1998 Graeme E Moss <[email protected]>
 ;; Maintainer: Stefan Monnier <[email protected]>
@@ -354,7 +355,38 @@ there."
   "Move forward to the first character that starts a top-level
 declaration.  As `haskell-ds-backward-decl' but forward."
   (interactive)
-  (haskell-ds-move-to-decl t (haskell-ds-bird-p) nil))
+  (let ((p (point)) b e empty was-at-bob)
+    ;; Go back to beginning of defun, then go to beginning of next
+    (haskell-ds-move-to-decl nil (haskell-ds-bird-p) nil)
+    (setq b (point))
+    (haskell-ds-move-to-decl t (haskell-ds-bird-p) nil)
+    (setq e (point))
+    ;; tests if line is empty
+    (setq empty (and (<= (point) p)
+                     (not (eolp))))
+    (setq was-at-bob (and (= (point-min) b)
+                          (= b p)
+                          (< p e)))
+    ;; this conditional allows for when empty lines at end, first
+    ;; `C-M-e' will go to end of defun, next will go to end of file.
+    (when (or was-at-bob
+              empty)
+      (if (or (and was-at-bob
+                   (= ?\n
+                      (save-excursion
+                        (goto-char (point-min))
+                        (following-char))))
+              empty)
+          (haskell-ds-move-to-decl t (haskell-ds-bird-p) nil))
+      ;; Then go back to end of current
+      (forward-line -1)
+      (while (and (eolp)
+                  ;; prevent infinite loop
+                  (not (= (point)
+                          (point-min))))
+        (forward-line -1))
+      (forward-line 1)))
+  (point))
 
 (defun haskell-ds-generic-find-next-decl (bird-literate)
   "Find the name, position and type of the declaration at or after point.

tests/haskell-decl-scan-tests.el

@@ -0,0 +1,97 @@
+;;; haskell-decl-scan-tests.el -*- lexical-binding: t -*-
+
+;; Copyright © 2016 Chris Gregory. All rights reserved.
+
+;; This file is part of haskell-mode package.
+;; You can contact with authors using GitHub issue tracker:
+;; https://github.com/haskell/haskell-mode/issues
+
+;; This file 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 3, or (at your option)
+;; any later version.
+
+;; This file 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., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
+
+;;; Commentary:
+
+;; This package provides regression tests for haskell-decl-scan package.
+
+;;; Code:
+
+(require 'ert)
+(require 'haskell-decl-scan)
+(require 'haskell-test-utils)
+
+(ert-deftest haskell-ds-backward-decl-1 ()
+  "Test running haskell-ds-backward-decl"
+  (with-temp-buffer
+    (insert-lines "" "fun :: Int -> Int" "fun = id"
+                  "" "f2 :: Int" "f2 = 3" "")
+    (goto-char (point-max))
+    (should (haskell-ds-backward-decl))
+    (should (looking-at-p "f2 :: Int"))
+    (should (haskell-ds-backward-decl))
+    (should (looking-at-p "fun :: Int -> Int"))
+    (should-not (haskell-ds-backward-decl))
+    (should (= (point-min) (point)))))
+
+(ert-deftest haskell-ds-backward-decl-2 ()
+  "Test running haskell-ds-backward-decl"
+  (with-temp-buffer
+    (insert-lines "" "" "fun :: Int -> Int"
+                  "" "" "fun = id"
+                  "" "" "f2 :: Int"
+                  "" "" "f2 = 3"
+                  "" "" "")
+    (goto-char (point-max))
+    (should (haskell-ds-backward-decl))
+    (should (looking-at-p "f2 :: Int"))
+    (should (haskell-ds-backward-decl))
+    (should (looking-at-p "fun :: Int -> Int"))
+    (should-not (haskell-ds-backward-decl))
+    (should (= (point-min) (point)))))
+
+(ert-deftest haskell-ds-forward-decl-1 ()
+  "Test running haskell-ds-backward-decl"
+  (with-temp-buffer
+    (insert-lines "" "fun :: Int -> Int" "fun = id"
+                  "" "f2 :: Int" "f2 = 3"
+                  "")
+    (goto-char (point-min))
+    (should (haskell-ds-forward-decl))
+    (should (looking-at-p "$"))
+    (should (= (point) (save-excursion (goto-line 4) (point))))
+    (should (haskell-ds-forward-decl))
+    (should (looking-at-p "f2 :: Int"))
+    (should (= (point-max) (haskell-ds-forward-decl)))))
+
+(ert-deftest haskell-ds-forward-decl-2 ()
+  "Test running haskell-ds-backward-decl"
+  (with-temp-buffer
+    (insert-lines "" "" "fun :: Int -> Int"
+                  "" "" "fun = id"
+                  "" "" "f2 :: Int"
+                  "" "" "f2 = 3"
+                  "" "" "")
+    (goto-char (point-min))
+    (should (haskell-ds-forward-decl))
+    (should (looking-at-p "$"))
+    (should (= (point) (save-excursion (goto-line 7) (point))))
+    (should (haskell-ds-forward-decl))
+    (should (looking-at-p "f2 :: Int"))
+    (should (haskell-ds-forward-decl))
+    (should (= (point) (save-excursion (goto-line 13) (point))))
+    (should (= (point-max) (progn (haskell-ds-forward-decl) (point))))))
+
+(provide 'haskell-decl-scan-tests)
+
+;;; haskell-decl-scan-tests.el ends here