Merge pull request #1463 from jfaz1/recent

Add recent file history

Author: cxxxr

src/commands/file.lisp

@@ -20,7 +20,10 @@
            :change-directory
            :current-directory
            :prompt-for-files-recursively
-           :format-current-buffer)
+           :format-current-buffer
+           :file-history
+           :find-history-file
+           :*file-history-limit*)
   #+sbcl
   (:lock t))
 (in-package :lem-core/commands/file)
@@ -29,6 +32,7 @@
 (define-key *global-keymap* "C-x C-r" 'read-file)
 (define-key *global-keymap* "C-x C-s" 'save-current-buffer)
 (define-key *global-keymap* "C-x C-w" 'write-file)
+(define-key *global-keymap* "C-x C-h" 'find-history-file)
 (define-key *global-keymap* "C-x Tab" 'insert-file)
 (define-key *global-keymap* "C-x s" 'save-some-buffers)
 
@@ -391,3 +395,40 @@ With prefix argument INSERT, insert the directory of the active buffer at point.
 
 Supported modes include: c-mode with clang-format, go-mode with gofmt, js-mode and json-mode with prettier, and lisp-mode. Additionally rust-mode uses rustfmt."
   (format-buffer))
+
+(defvar *files-history*)
+(defvar *file-history-limit* 10
+  "The maximum number of files to keep in the file history.")
+  
+(defun file-history ()
+  "Return or create the files' history struct.
+  The history file is saved on (lem-home)/history/files"
+  (unless (boundp '*files-history*)
+    (let* ((pathname (merge-pathnames "history/files" (lem-home)))
+           (history (lem/common/history:make-history :pathname pathname :limit *file-history-limit*)))
+      (setf *files-history* history)))
+  *files-history*)
+
+(defun add-to-file-history (buffer)
+  "Add the buffer's filename to the file history."
+  (let ((filename (buffer-filename buffer)))
+    (when filename
+      (lem/common/history:add-history (file-history) 
+                                      (namestring filename)
+                                      :allow-duplicates nil)
+      (lem/common/history:save-file (file-history)))))
+
+(add-hook *find-file-hook* 'add-to-file-history)
+
+(define-command find-history-file () ()
+  "Prompt for a file from the file history and open it."
+  (let* ((history (file-history))
+         (candidates (lem/common/history:history-data-list history)))
+    (if candidates
+        (let ((filename (prompt-for-string
+                         "File: "
+                         :completion-function (lambda (x) (completion-strings x (reverse candidates)))
+                         :test-function (lambda (name) (member name candidates :test #'string=)))))
+          (when filename
+            (find-file filename)))
+        (editor-error "No file history."))))

src/common/history.lisp

@@ -20,7 +20,8 @@
   pathname
   data
   index
-  edit-string)
+  edit-string
+  limit)
 
 (defun history-data-list (history)
   "Return the history data as a list (and not a vector)."
@@ -31,15 +32,16 @@
   (and (not (equal input last-input))
        (not (equal input ""))))
 
-(defun make-history (&key pathname)
+(defun make-history (&key pathname limit)
   (let* ((initial-contents
            (when (and pathname (uiop:file-exists-p pathname))
              (uiop:read-file-form pathname)))
          (num-contents (length initial-contents)))
     (%make-history
      :pathname pathname
      :data (make-array num-contents :fill-pointer num-contents :adjustable t :initial-contents initial-contents)
-     :index num-contents)))
+     :index num-contents
+     :limit limit)))
 
 (defun save-file (history)
   (when (history-pathname history)
@@ -59,19 +61,26 @@
   "Add this input to the history.
 
   Don't add the same input as the previous one.
-  If allow-duplicates is non t, don't add duplicates at all."
-  (cond
-    ((not allow-duplicates)
-     (when (not (find input (history-data history) :test test))
-       (vector-push-extend input (history-data history))))
-    ((require-additions-to-history-p input
-                                     (last-history history))
-     (vector-push-extend input (history-data history)))
-    (t
-     nil))
-
-  (setf (history-index history)
-        (length (history-data history)))
+  If allow-duplicates is non t, don't add duplicates at all.
+  If limit is set, overwrite oldest entry when reached."
+  (when (or allow-duplicates
+            (not (find input (history-data history) :test test)))
+    (when (require-additions-to-history-p input (last-history history))
+      (let ((limit (history-limit history)))
+        (cond
+          ((and limit (>= (length (history-data history)) limit))
+           ;; Shift by 1, overwriting the oldest
+           (replace (history-data history)
+                    (history-data history)
+                    :start1 0 
+                    :start2 1
+                    :end2 limit)
+           (setf (aref (history-data history) (1- limit)) input))
+          (t
+           ;; Add new element normally
+           (vector-push-extend input (history-data history)))))
+      (setf (history-index history)
+            (length (history-data history)))))
   input)
 
 (defun remove-history (history input)