lisp/org-element.el: Add repeater-deadline support to org-element

* lisp/org-element.el (org-element-timestamp-parser,
org-element-timestamp-interpreter): Add support for repeater
deadlines.  Adds two new properties: ':repeater-deadline-value' and
':repeater-deadline-unit'.

* testing/lisp/test-org-element.el (test-org-element/timestamp-parser,
test-org-element/timestamp-interpreter): Test support for repeater
deadlines.

* etc/ORG-NEWS: Add relevant news.

3 files changed, 100 insertions, 22 deletions

diff --git a/etc/ORG-NEWS b/etc/ORG-NEWS
index aeb7ffd4b..e61bd6988 100644
--- a/etc/ORG-NEWS
+++ b/etc/ORG-NEWS
@@ -512,6 +512,22 @@ timestamp object.  Possible values: ~timerange~, ~daterange~, ~nil~.
 ~org-element-timestamp-interpreter~ takes into account this property
 and returns an appropriate timestamp string.
 
+**** New properties =:repeater-deadline-value= and =:repeater-deadline-unit= for org-element timestamp object
+
+~org-element-timestamp-parser~ now adds =:repeater-deadline-value= and
+=:repeater-deadline-unit= properties to each timestamp object that has
+a repeater deadline.  For example, in =<2012-03-29 Thu ++1y/2y>=, =2y=
+is the repeater deadline with a value of =2= and unit of =y=.  See
+"5.3.3 Tracking your habits" section in the manual.
+
+Possible values for =:repeater-deadline-value=: ~positive integer~, ~nil~.
+
+Possible values for =:repeater-deadline-unit=: ~hour~, ~day~, ~week~,
+~month~, ~year~.
+
+~org-element-timestamp-interpreter~ takes into account these properties
+and returns an appropriate timestamp string.
+
 **** =org-link= store functions are passed an ~interactive?~ argument
 
 The ~:store:~ functions set for link types using
diff --git a/lisp/org-element.el b/lisp/org-element.el
index 8e5416d8b..e7561f16f 100644
--- a/lisp/org-element.el
+++ b/lisp/org-element.el
@@ -4288,12 +4288,13 @@ Assume point is at the target."
   "Parse time stamp at point, if any.
 
 When at a time stamp, return a new syntax node of `timestamp' type
-containing `:type', `:range-type', `:raw-value', `:year-start', `:month-start',
-`:day-start', `:hour-start', `:minute-start', `:year-end',
-`:month-end', `:day-end', `:hour-end', `:minute-end',
+containing `:type', `:range-type', `:raw-value', `:year-start',
+`:month-start', `:day-start', `:hour-start', `:minute-start',
+`:year-end', `:month-end', `:day-end', `:hour-end', `:minute-end',
 `:repeater-type', `:repeater-value', `:repeater-unit',
-`:warning-type', `:warning-value', `:warning-unit', `:begin', `:end'
-and `:post-blank' properties.  Otherwise, return nil.
+`:repeater-deadline-value', `:repeater-deadline-unit', `:warning-type',
+`:warning-value', `:warning-unit', `:begin', `:end' and `:post-blank'
+properties.  Otherwise, return nil.
 
 Assume point is at the beginning of the timestamp."
   (when (looking-at-p org-element--timestamp-regexp)
@@ -4326,20 +4327,38 @@ Assume point is at the beginning of the timestamp."
                           (date-end 'daterange)
                           (time-range 'timerange)
                           (t nil)))
-	     (repeater-props
-	      (and (not diaryp)
-		   (string-match "\\([.+]?\\+\\)\\([0-9]+\\)\\([hdwmy]\\)"
-				 raw-value)
-		   (list
-		    :repeater-type
-		    (let ((type (match-string 1 raw-value)))
-		      (cond ((equal "++" type) 'catch-up)
-			    ((equal ".+" type) 'restart)
-			    (t 'cumulate)))
-		    :repeater-value (string-to-number (match-string 2 raw-value))
-		    :repeater-unit
-		    (pcase (string-to-char (match-string 3 raw-value))
-		      (?h 'hour) (?d 'day) (?w 'week) (?m 'month) (_ 'year)))))
+             (repeater-props
+              (and (not diaryp)
+                   (string-match
+                    (rx
+                     (group-n 1 (or "+" "++" ".+"))
+                     (group-n 2 (+ digit))
+                     (group-n 3 (any "hdwmy"))
+                     (optional
+                      "/"
+                      (group-n 4 (+ digit))
+                      (group-n 5 (any "hdwmy"))))
+                    raw-value)
+                   (nconc
+                    (list
+                     :repeater-type
+                     (let ((type (match-string 1 raw-value)))
+                       (cond ((equal "++" type) 'catch-up)
+                             ((equal ".+" type) 'restart)
+                             (t 'cumulate)))
+                     :repeater-value (string-to-number (match-string 2 raw-value))
+                     :repeater-unit
+                     (pcase (string-to-char (match-string 3 raw-value))
+                       (?h 'hour) (?d 'day) (?w 'week) (?m 'month) (_ 'year)))
+
+                    (let ((repeater-deadline-value (match-string 4 raw-value))
+                          (repeater-deadline-unit (match-string 5 raw-value)))
+                      (when (and repeater-deadline-value repeater-deadline-unit)
+                        (list
+                         :repeater-deadline-value (string-to-number repeater-deadline-value)
+                         :repeater-deadline-unit
+                         (pcase (string-to-char repeater-deadline-unit)
+                           (?h 'hour) (?d 'day) (?w 'week) (?m 'month) (_ 'year))))))))
 	     (warning-props
 	      (and (not diaryp)
 		   (string-match "\\(-\\)?-\\([0-9]+\\)\\([hdwmy]\\)" raw-value)
@@ -4407,7 +4426,16 @@ Assume point is at the beginning of the timestamp."
 	             (let ((val (org-element-property :repeater-value timestamp)))
 	               (and val (number-to-string val)))
 	             (pcase (org-element-property :repeater-unit timestamp)
-	               (`hour "h") (`day "d") (`week "w") (`month "m") (`year "y"))))
+	               (`hour "h") (`day "d") (`week "w") (`month "m") (`year "y"))
+                     (when-let ((repeater-deadline-value
+                                 (org-element-property :repeater-deadline-value timestamp))
+                                (repeater-deadline-unit
+                                 (org-element-property :repeater-deadline-unit timestamp)))
+                       (concat
+                        "/"
+                        (number-to-string repeater-deadline-value)
+                        (pcase repeater-deadline-unit
+                          (`hour "h") (`day "d") (`week "w") (`month "m") (`year "y"))))))
                    (range-type (org-element-property :range-type timestamp))
                    (warning-string
 	            (concat
diff --git a/testing/lisp/test-org-element.el b/testing/lisp/test-org-element.el
index c49dc80d1..ddd601690 100644
--- a/testing/lisp/test-org-element.el
+++ b/testing/lisp/test-org-element.el
@@ -3208,12 +3208,19 @@ Outside list"
      (let ((timestamp (org-element-context)))
        (or (org-element-property :hour-end timestamp)
 	   (org-element-property :minute-end timestamp)))))
-  ;; With repeater, warning delay and both.
+  ;; With repeater, repeater deadline, warning delay and combinations.
   (should
    (eq 'catch-up
        (org-test-with-temp-text "<2012-03-29 Thu ++1y>"
 	 (org-element-property :repeater-type (org-element-context)))))
   (should
+   (equal '(catch-up 2 year)
+       (org-test-with-temp-text "<2012-03-29 Thu ++1y/2y>"
+         (let ((ts (org-element-context)))
+           (list (org-element-property :repeater-type ts)
+                 (org-element-property :repeater-deadline-value ts)
+                 (org-element-property :repeater-deadline-unit ts))))))
+  (should
    (eq 'first
        (org-test-with-temp-text "<2012-03-29 Thu --1y>"
 	 (org-element-property :warning-type (org-element-context)))))
@@ -3223,6 +3230,14 @@ Outside list"
 	    (let ((ts (org-element-context)))
 	      (list (org-element-property :repeater-type ts)
 		    (org-element-property :warning-type ts))))))
+  (should
+   (equal '(cumulate all 2 year)
+          (org-test-with-temp-text "<2012-03-29 Thu +1y/2y -1y>"
+            (let ((ts (org-element-context)))
+              (list (org-element-property :repeater-type ts)
+                    (org-element-property :warning-type ts)
+                    (org-element-property :repeater-deadline-value ts)
+                    (org-element-property :repeater-deadline-unit ts))))))
   ;; :range-type property
   (should
    (eq
@@ -3963,7 +3978,7 @@ DEADLINE: <2012-03-29 thu.> SCHEDULED: <2012-03-29 thu.> CLOSED: [2012-03-29 thu
   ;; Diary.
   (should (equal (org-test-parse-and-interpret "<%%diary-float t 4 2>")
 		 "<%%diary-float t 4 2>\n"))
-  ;; Timestamp with repeater interval, with delay, with both.
+  ;; Timestamp with repeater interval, repeater deadline, with delay, with combinations.
   (should
    (string-match "<2012-03-29 .* \\+1y>"
 		 (org-test-parse-and-interpret "<2012-03-29 thu. +1y>")))
@@ -3977,6 +3992,15 @@ DEADLINE: <2012-03-29 thu.> SCHEDULED: <2012-03-29 thu.> CLOSED: [2012-03-29 thu
      nil)))
   (should
    (string-match
+    "<2012-03-29 .* \\+1y/2y>"
+    (org-element-timestamp-interpreter
+     '(timestamp
+       (:type active :year-start 2012 :month-start 3 :day-start 29
+              :repeater-type cumulate :repeater-value 1 :repeater-unit year
+              :repeater-deadline-value 2 :repeater-deadline-unit year))
+     nil)))
+  (should
+   (string-match
     "<2012-03-29 .* -1y>"
     (org-element-timestamp-interpreter
      '(timestamp
@@ -3992,6 +4016,16 @@ DEADLINE: <2012-03-29 thu.> SCHEDULED: <2012-03-29 thu.> CLOSED: [2012-03-29 thu
 	      :warning-type all :warning-value 1 :warning-unit year
 	      :repeater-type cumulate :repeater-value 1 :repeater-unit year))
      nil)))
+  (should
+   (string-match
+    "<2012-03-29 .* \\+1y/2y -1y>"
+    (org-element-timestamp-interpreter
+     '(timestamp
+       (:type active :year-start 2012 :month-start 3 :day-start 29
+              :warning-type all :warning-value 1 :warning-unit year
+              :repeater-type cumulate :repeater-value 1 :repeater-unit year
+              :repeater-deadline-value 2 :repeater-deadline-unit year))
+     nil)))
   ;; Timestamp range with repeater interval
   (should
    (string-match "<2012-03-29 .* \\+1y>--<2012-03-30 .* \\+1y>"