Update haskell-indentation-indent-line

haskell-indentation.el

@@ -243,24 +243,40 @@ indentation points to the right, we switch going to the left."
   ;; try to repeat
   (when (not (haskell-indentation-indent-line-repeat))
     (setq haskell-indentation-dyn-last-direction nil)
-    ;; parse error is intentionally not cought here, it may come from
+    ;; parse error is intentionally not caught here, it may come from
     ;; `haskell-indentation-find-indentations', but escapes the scope
-    ;; and aborts the opertaion before any moving happens
+    ;; and aborts the operation before any moving happens
     (let* ((cc (current-column))
            (ci (haskell-indentation-current-indentation))
            (inds (save-excursion
                    (move-to-column ci)
                    (or (haskell-indentation-find-indentations)
                        '(0))))
            (valid (memq ci inds))
-           (cursor-in-whitespace (< cc ci)))
-
+           (cursor-in-whitespace (< cc ci))
+           ;; certain evil commands need the behaviour seen in
+           ;; `haskell-indentation-newline-and-indent'
+           (evil-special-command (and (bound-and-true-p evil-mode)
+                                      (memq this-command '(evil-open-above
+                                                           evil-open-below
+                                                           evil-replace))))
+           (on-last-indent (eq ci (car (last inds)))))
       (if (and valid cursor-in-whitespace)
           (move-to-column ci)
         (haskell-indentation-reindent-to
-         (haskell-indentation-next-indentation ci inds 'nofail)
+         (funcall
+          (if on-last-indent
+              #'haskell-indentation-previous-indentation
+            #'haskell-indentation-next-indentation)
+          (if evil-special-command
+              (save-excursion
+                (end-of-line 0)
+                (1- (haskell-indentation-current-indentation)))
+            ci)
+          inds
+          'nofail)
          cursor-in-whitespace))
-      (setq haskell-indentation-dyn-last-direction 'right
+      (setq haskell-indentation-dyn-last-direction (if on-last-indent 'left 'right)
             haskell-indentation-dyn-last-indentations inds))))
 
 (defun haskell-indentation-indent-line-repeat ()

tests/haskell-indentation-tests.el

@@ -946,4 +946,47 @@ data Foo = Bar
     (execute-kbd-macro (kbd "M-j"))
     (should (equal 3 (- (point) (line-beginning-position))))))
 
+(ert-deftest haskell-indentation-cycle ()
+  "Test if the indentation cycles properly."
+  (with-temp-buffer
+    (haskell-mode)
+    (insert "
+test = test' []
+  where
+    test' = test''
+      where
+        test'' :: [a] -> [a]
+      test'' = something")
+    (let* ((inds (save-excursion
+                   (move-to-column (haskell-indentation-current-indentation))
+                   (haskell-indentation-find-indentations)))
+           (count (1- (length inds)))
+           (current count))
+      (should (eq count 3))
+      (setq current 2)                  ; will be at third position
+      ;; do first indent as normal
+      (haskell-indentation-indent-line)
+      (should (eq (haskell-indentation-current-indentation)
+                  (nth current inds)))
+      ;; indent until the max indent position
+      ;; behave as if re-indenting
+      (while (< current count)
+        (cl-incf current)
+        (let ((last-command 'indent-for-tab-command))
+          (haskell-indentation-indent-line))
+        (should (eq (haskell-indentation-current-indentation)
+                    (nth current inds))))
+      ;; start to indent backwards
+      (cl-decf current)
+      (haskell-indentation-indent-line)
+      (should (eq (haskell-indentation-current-indentation)
+                  (nth current inds)))
+      ;; indent back the rest of the way
+      (while (> current 0)
+        (cl-decf current)
+        (let ((last-command 'indent-for-tab-command))
+          (haskell-indentation-indent-line))
+        (should (eq (haskell-indentation-current-indentation)
+                    (nth current inds)))))))
+
 ;;; haskell-indentation-tests.el ends here