[nongnu] elpa/undo-fu 88c4086e12 43/82: Add 'undo-fu-ignore-keyboard-quit' & 'undo-fu-disable-checkpoint'

[ELPA Syncer]

branch: elpa/undo-fu
commit 88c4086e12707de2a125132f18f7586f23441b61
Author: Campbell Barton <ideasman42@gmail.com>
Commit: Campbell Barton <ideasman42@gmail.com>

    Add 'undo-fu-ignore-keyboard-quit' & 'undo-fu-disable-checkpoint'
    
    This is an option (off by default) that allows explicitly
    activating non-linear behavior as 'keyboard-quit' could
    be used for other reasons where it's possible to accidentally
    activate non-linear behavior.
    
    Resolves #6
---
 changelog.rst |  5 +++++
 readme.rst    |  7 +++++++
 undo-fu.el    | 53 ++++++++++++++++++++++++++++++++++++++++++++++-------
 3 files changed, 58 insertions(+), 7 deletions(-)

diff --git a/changelog.rst b/changelog.rst
index ce37041db8..51579514e7 100644
--- a/changelog.rst
+++ b/changelog.rst
@@ -3,6 +3,11 @@
 Change Log
 ##########
 
+- In development.
+
+  - Add ``undo-fu-ignore-keyboard-quit`` option for explicit non-linear 
behavior.
+  - Support using ``undo-fu-only-redo`` after regular ``undo`` / ``undo-only``.
+
 - Version 0.2 (2020-01-12)
 
   - Linear redo support (which wont undo).
diff --git a/readme.rst b/readme.rst
index 915c177465..f8a41cef82 100644
--- a/readme.rst
+++ b/readme.rst
@@ -37,6 +37,7 @@ This package exposes the following functions:
 - ``undo-fu-only-undo``
 - ``undo-fu-only-redo``
 - ``undo-fu-only-redo-all``
+- ``undo-fu-disable-checkpoint`` (only needed when 
``undo-fu-ignore-keyboard-quit`` is in use).
 
 
 Key Bindings
@@ -83,6 +84,12 @@ Customization
 
    When this boolean is ``t``, undoing with a selection
    will use undo within this region.
+``undo-fu-ignore-keyboard-quit``
+   Don't use ``Ctrl-G`` (``keyboard-quit``) for non-linear behavior,
+   instead, use the ``undo-fu-disable-checkpoint`` command.
+
+   This was added for users who prefer to explicitly activate this behavior.
+   As ``keyboard-quit`` may be used for other reasons.
 
 
 Limitations
diff --git a/undo-fu.el b/undo-fu.el
index 247037b1e1..efe14712f0 100644
--- a/undo-fu.el
+++ b/undo-fu.el
@@ -53,6 +53,13 @@ causing undo-fu to work with reduced functionality when a 
selection exists."
   :group 'undo-fu
   :type 'boolean)
 
+(defcustom undo-fu-ignore-keyboard-quit nil
+  "When t, don't use `keyboard-quit' to disable linear undo/redo behavior.
+
+Instead, explicitly call `undo-fu-disable-checkpoint'."
+  :group 'undo-fu
+  :type 'boolean)
+
 ;; ---------------------------------------------------------------------------
 ;; Internal Variables
 
@@ -143,6 +150,28 @@ Returns the number of steps to reach this list or 
COUNT-LIMIT."
 ;; ---------------------------------------------------------------------------
 ;; Public Functions
 
+;;;###autoload
+(defun undo-fu-disable-checkpoint ()
+  "Remove the undo-fu checkpoint, making all future actions unconstrained.
+
+This command is needed when `undo-fu-ignore-keyboard-quit' is t,
+since in this case `keyboard-quit' cannot be used
+to perform unconstrained undo/redo actions."
+  (interactive)
+  (message "Undo end-point cleared!")
+  (undo-fu--checkpoint-disable)
+
+  ;; Needed not to interfere with undo/redo stepping behavior.
+  (let*
+    ( ;; Assign for convenience.
+      (was-undo (not (null (member last-command '(undo undo-fu-only-undo)))))
+      (was-redo (not (null (member last-command '(undo-fu-only-redo)))))
+      (was-undo-or-redo (or was-undo was-redo)))
+
+    (when was-undo-or-redo
+      (setq this-command last-command)
+      (setq real-this-command real-last-command))))
+
 ;;;###autoload
 (defun undo-fu-only-redo-all ()
   "Redo all actions until the initial undo step.
@@ -167,7 +196,11 @@ Optional argument ARG The number of steps to redo."
     ( ;; Assign for convenience.
       (was-undo (not (null (member last-command '(undo undo-fu-only-undo)))))
       (was-redo (not (null (member last-command '(undo-fu-only-redo)))))
-      (was-undo-or-redo (or was-undo was-redo)))
+      (was-undo-or-redo (or was-undo was-redo))
+      (undo-fu-quit-command
+        (if undo-fu-ignore-keyboard-quit
+          'undo-fu-disable-checkpoint
+          'keyboard-quit)))
 
     ;; Reset the option to not respect the checkpoint
     ;; after running non-undo related commands.
@@ -190,7 +223,7 @@ Optional argument ARG The number of steps to redo."
     ;; This allows explicitly over-stepping the boundary,
     ;; in cases when users want to bypass this constraint.
     (when undo-fu--respect
-      (when (string-equal last-command 'keyboard-quit)
+      (when (member last-command (list undo-fu-quit-command 
'undo-fu-disable-checkpoint))
         (undo-fu--checkpoint-disable)
         (message "Redo end-point stepped over!")))
 
@@ -234,8 +267,8 @@ Optional argument ARG The number of steps to redo."
                 ;; Ensure the next steps is a redo action.
                 (when (zerop steps-test)
                   (user-error
-                    "Redo step not found (%s to ignore)"
-                    (substitute-command-keys "\\[keyboard-quit]")))
+                    "Redo end-point reached (%s to ignore)"
+                    (substitute-command-keys (format "\\[%s]" (symbol-name 
undo-fu-quit-command)))))
 
                 steps-test)
 
@@ -282,7 +315,11 @@ Optional argument ARG the number of steps to undo."
     ( ;; Assign for convenience.
       (was-undo (not (null (member last-command '(undo undo-fu-only-undo)))))
       (was-redo (not (null (member last-command '(undo-fu-only-redo)))))
-      (was-undo-or-redo (or was-undo was-redo)))
+      (was-undo-or-redo (or was-undo was-redo))
+      (undo-fu-quit-command
+        (if undo-fu-ignore-keyboard-quit
+          'undo-fu-disable-checkpoint
+          'keyboard-quit)))
 
     ;; Reset the option to not respect the checkpoint
     ;; after running non-undo related commands.
@@ -305,9 +342,10 @@ Optional argument ARG the number of steps to undo."
         (deactivate-mark)))
 
     ;; Allow crossing the boundary, if we press [keyboard-quit].
-    ;; This allows explicitly over-stepping the boundary, in cases where it's 
needed.
+    ;; This allows explicitly over-stepping the boundary,
+    ;; in cases when users want to bypass this constraint.
     (when undo-fu--respect
-      (when (string-equal last-command 'keyboard-quit)
+      (when (member last-command (list undo-fu-quit-command 
'undo-fu-disable-checkpoint))
         (undo-fu--checkpoint-disable)
         (message "Undo end-point ignored!")))
 
@@ -351,6 +389,7 @@ Optional argument ARG the number of steps to undo."
   'evil
   '
   (progn
+    (evil-declare-not-repeat 'undo-fu-disable-checkpoint)
     (evil-declare-not-repeat 'undo-fu-only-undo)
     (evil-declare-not-repeat 'undo-fu-only-redo)
     (evil-declare-not-repeat 'undo-fu-only-redo-all)))