feat: add the 'oldest sort method to sort by creation day, ascending

README.md

@@ -82,7 +82,7 @@ When you finish looking at Z, you close perspective `feature-Z`, and return to
 Y, you close perspective `bugfix-Y` and return to `feature-X`.
 
 (Hint: this workflow works best with the `persp-sort` variable set to `'created`
-— see documentation below.)
+or `'oldest` — see documentation below.)
 
 
 ### Perspective Merging
@@ -245,7 +245,7 @@ The actual command keys (the ones pressed after the prefix) are defined in
 - `s` — `persp-switch`: Query a perspective to switch to, or create
 - `` ` `` — `persp-switch-by-number`: Switch to perspective by number, or switch
   quickly using numbers `1, 2, 3.. 0` as prefix args; note this will probably be
-  most useful with `persp-sort` set to `'created`
+  most useful with `persp-sort` set to `'created` or `'oldest`
 - `k` — `persp-remove-buffer`: Query a buffer to remove from current perspective
 - `c` — `persp-kill` : Query a perspective to kill
 - `r` — `persp-rename`: Rename current perspective
@@ -425,9 +425,11 @@ customize`). The following are likely to be of most interest:
 
 - `persp-sort`: Select the order in which to sort perspectives when calling
   `persp-switch`. Defaults to `'name` (alphabetical), but `'access` (by most
-  recently accessed) and `'created` (by order created) are available. Note that
+  recently accessed), `'created` (by order created, descending) and `'oldest`
+  (by order created, ascending) are available. Note that
   `persp-switch-by-number` is likely to be confusing when this is set to
-  `'access`, as the numbers associated with a perspective will change all the time.
+  `'access`, as the numbers associated with a perspective will change all the
+  time.
 - `persp-interactive-completion-function`: Used for prompting for a perspective
   name. `completing-read` is the default, with `ido-completing-read` enabled
   with `ido-mode`. `ivy-completing-read` is broadly compatible, but

perspective.el

@@ -99,11 +99,13 @@ instead of the full perspective list."
   "What order to sort perspectives.
 If 'name, then sort alphabetically.
 If 'access, then sort by last time accessed (latest first).
-If 'created, then sort by time created (latest first)."
+If 'created, then sort by time created (latest first).
+If 'oldest, then sort by time created (oldest first)"
   :group 'perspective-mode
   :type '(choice (const :tag "By Name"          name)
                  (const :tag "By Time Accessed" access)
-                 (const :tag "By Time Created"  created)))
+                 (const :tag "By Time Created (descending)"  created)
+                 (const :tag "By Time Created (ascending)" oldest)))
 
 (defcustom persp-frame-global-perspective-name "GLOBAL"
   "The name for a frames global perspective."
@@ -584,11 +586,12 @@ perspective-local variables to `persp-curr'"
   "Return a list of the names of all perspectives on the `selected-frame'.
 
 If `persp-sort' is 'name (the default), then return them sorted
-alphabetically. If `persp-sort' is 'access, then return them
-sorted by the last time the perspective was switched to, the
-current perspective being the first. If `persp-sort' is 'created,
-then return them in the order they were created, with the newest
-first."
+alphabetically. If `persp-sort' is 'access, then return them sorted by
+the last time the perspective was switched to, the current perspective
+being the first. If `persp-sort' is 'created, then return them in the
+order they were created, with the newest first. If `persp-sort' is
+'oldest, then return them in the order they were created, with the
+oldest first."
   (let ((persps (hash-table-values (perspectives-hash))))
     (cond ((eq persp-sort 'name)
            (sort (mapcar 'persp-name persps) 'string<))
@@ -601,7 +604,12 @@ first."
            (mapcar 'persp-name
                    (sort persps (lambda (a b)
                                   (time-less-p (persp-created-time b)
-                                               (persp-created-time a)))))))))
+                                               (persp-created-time a))))))
+          ((eq persp-sort 'oldest)
+           (mapcar 'persp-name
+                   (sort persps (lambda (a b)
+                                  (time-less-p (persp-created-time a)
+                                               (persp-created-time b)))))))))
 
 (defun persp-all-names (&optional not-frame)
   "Return a list of the perspective names for all frames.

test/test-perspective.el

@@ -2229,17 +2229,32 @@ persp-test-make-sample-environment."
 
 (ert-deftest issue-90-persp-last--vs--persp-find-some ()
   (persp-test-with-persp
-   (let ((persp-sort 'created))         ; this should be respected when killing
-     (should-persp-equal       '("main")             "main" nil    "main")
-     (with-named-persp "A"
-       (should-persp-equal     '("A" "main")         "A"    "main" "main")
-       (with-named-persp "B"
-         (should-persp-equal   '("B" "A" "main")     "B"    "A"    "A")
-         (with-named-persp "C"
-           (should-persp-equal '("C" "B" "A" "main") "C"    "B"    "B")) ; pop C
-         (should-persp-equal   '("B" "A" "main")     "B"    nil    "B")) ; pop B
-       (should-persp-equal     '("A" "main")         "A"    nil    "A")) ; pop A
-     (should-persp-equal       '("main")             "main" nil    "main"))))
+    (let ((persp-sort 'created))         ; this should be respected when killing
+      (should-persp-equal       '("main")             "main" nil    "main")
+      (with-named-persp "A"
+        (should-persp-equal     '("A" "main")         "A"    "main" "main")
+        (with-named-persp "B"
+          (should-persp-equal   '("B" "A" "main")     "B"    "A"    "A")
+          (with-named-persp "C"
+            (should-persp-equal '("C" "B" "A" "main") "C"    "B"    "B")) ; pop C
+          (should-persp-equal   '("B" "A" "main")     "B"    nil    "B")) ; pop B
+        (should-persp-equal     '("A" "main")         "A"    nil    "A")) ; pop A
+      (should-persp-equal       '("main")             "main" nil    "main"))))
+
+(ert-deftest sort-by-oldest ()
+  (persp-test-with-persp
+    (let ((persp-sort 'oldest))
+      ;;                         persp-order          curr   last   find-some
+      (should-persp-equal       '("main")             "main" nil    "main")
+      (with-named-persp "A"
+        (should-persp-equal     '("main" "A")         "A"    "main" "main")
+        (with-named-persp "B"
+          (should-persp-equal   '("main" "A" "B")     "B"    "A"    "A")
+          (with-named-persp "C"
+            (should-persp-equal '("main" "A" "B" "C") "C"    "B"    "B"))
+          (should-persp-equal   '("main" "A" "B")     "B"    nil    "main"))
+        (should-persp-equal     '("main" "A")         "main" nil    "main"))
+      (should-persp-equal       '("main")             "main" nil    "main"))))
 
 (ert-deftest state-save-and-load ()
   (unwind-protect