Restore previous behavior for inherited tags, now just more flexible

* org.el (org-get-tags-at): Remove duplicate inherited tags.

* org-agenda.el (org-agenda-show-inherited-tags): Allow to be
set to 'always or to a list of agenda types.
(org-agenda-finalize): Rework conditions under which inherited
tags should be made available even when not displayed.
(org-search-view, org-agenda-get-todos)
(org-agenda-get-timestamps, org-agenda-get-sexps)
(org-agenda-get-progress, org-agenda-get-scheduled)
(org-agenda-get-blocks): Use new possible values of
`org-agenda-show-inherited-tags'.

Thanks to Karl Voit and Tassilo Horn who first reported this.

lisp/org-agenda.el

@@ -1648,26 +1648,53 @@ When non-nil, this must be the number of minutes, e.g. 60 for one hour."
 	  (const :tag "No default duration")))
 
 (defcustom org-agenda-show-inherited-tags t
-  "Non-nil means show inherited tags in each agenda line."
+  "Non-nil means show inherited tags in each agenda line.
+
+When this option is set to 'always, it take precedences over
+`org-agenda-use-tag-inheritance' and inherited tags are shown
+in every agenda.
+
+When this option is set to t (the default), inherited tags are
+shown when they are available, i.e. when the value of
+`org-agenda-use-tag-inheritance' has been taken into account.
+
+This can be set to a list of agenda types in which the agenda
+must display the inherited tags.  Available types are 'todo,
+'agenda, 'search and 'timeline.
+
+When set to nil, never show inherited tags in agenda lines."
   :group 'org-agenda-line-format
-  :type 'boolean)
+  :group 'org-agenda
+  :version "24.3"
+  :type '(choice
+	  (const :tag "Show inherited tags when available" t)
+	  (const :tag "Always show inherited tags" 'always)
+	  (repeat :tag "Show inherited tags only in selected agenda types"
+		  (symbol :tag "Agenda type"))))
 
 (defcustom org-agenda-use-tag-inheritance '(todo search timeline agenda)
   "List of agenda view types where to use tag inheritance.
 
 In tags/tags-todo/tags-tree agenda views, tag inheritance is
 controlled by `org-use-tag-inheritance'.  In other agenda types,
-`org-use-tag-inheritance' is not used when selecting the agenda
-entries, but you may want the agenda to use the inherited tags
-anyway, e.g. for later tag filtering.
+`org-use-tag-inheritance' is not used for the selection of the
+agenda entries.  Still, you may want the agenda to be aware of
+the inherited tags anyway, e.g. for later tag filtering.
 
-The default value reset tags in every agenda type.  Setting this
-option to nil will speed up non-tags agenda view a lot.
+Allowed value are 'todo, 'search, 'timeline and 'agenda.
 
-Allowed value are 'todo, 'search, 'timeline and 'agenda."
-  :version "24.3"
+This variable has no effect if `org-agenda-show-inherited-tags'
+is set to 'always.  In that case, the agenda is aware of those
+tags.
+
+The default value sets tags in every agenda type.  Setting this
+option to nil will speed up non-tags agenda view a lot."
   :group 'org-agenda
-  :type '(repeat (symbol :tag "Agenda type")))
+  :version "24.3"
+  :type '(choice
+	  (const :tag "Use tag inheritance in all agenda types" t)
+	  (repeat :tag "Use tag inheritance in selected agenda types"
+		  (symbol :tag "Agenda type"))))
 
 (defcustom org-agenda-hide-tags-regexp nil
   "Regular expression used to filter away specific tags in agenda views.
@@ -3569,8 +3596,14 @@ generating a new one."
 		 (save-excursion (next-single-property-change (point-min) 'org-habit-p)))
 	    (org-habit-insert-consistency-graphs))
 	(setq org-agenda-type (org-get-at-bol 'org-agenda-type))
-	(when (delq nil (mapcar (lambda (tp) (org-agenda-check-type nil tp))
-				org-agenda-use-tag-inheritance))
+	(unless (or (eq org-agenda-show-inherited-tags 'always)
+		    (and (listp org-agenda-show-inherited-tags)
+			 (memq org-agenda-type org-agenda-show-inherited-tags))
+		    (and (eq org-agenda-show-inherited-tags t)
+			 (or (eq org-agenda-use-tag-inheritance t)
+			     (and (listp org-agenda-use-tag-inheritance)
+				  (not (memq org-agenda-type
+					     org-agenda-use-tag-inheritance))))))
 	  (let (mrk)
 	    (save-excursion
 	      (goto-char (point-min))
@@ -4290,7 +4323,7 @@ in `org-agenda-text-search-extra-files'."
 		      'help-echo (format "mouse-2 or RET jump to location")))
 	 (full-words org-agenda-search-view-force-full-words)
 	 (org-agenda-text-search-extra-files org-agenda-text-search-extra-files)
-	 regexp rtn rtnall files file pos
+	 regexp rtn rtnall files file pos inherited-tags
 	 marker category category-pos tags c neg re boolean
 	 ee txt beg end words regexps+ regexps- hdl-only buffer beg1 str)
     (unless (and (not edit-at)
@@ -4444,7 +4477,13 @@ in `org-agenda-text-search-extra-files'."
 			(setq marker (org-agenda-new-marker (point))
 			      category (org-get-category)
 			      category-pos (get-text-property (point) 'org-category-position)
-			      tags (org-get-tags-at nil t)
+			      inherited-tags
+			      (or (eq org-agenda-show-inherited-tags 'always)
+				  (memq 'todo org-agenda-show-inherited-tags)
+				  (and (eq org-agenda-show-inherited-tags t)
+				       (or (eq org-agenda-use-tag-inheritance t)
+					   (memq 'todo org-agenda-use-tag-inheritance))))
+			      tags (org-get-tags-at nil (not inherited-tags))
 			      txt (org-agenda-format-item
 				   ""
 				   (buffer-substring-no-properties
@@ -5250,7 +5289,7 @@ the documentation of `org-diary'."
 					      "\\|") "\\)"))
 			  (t org-not-done-regexp))))
 	 marker priority category category-pos tags todo-state
-	 ee txt beg end)
+	 ee txt beg end inherited-tags)
     (goto-char (point-min))
     (while (re-search-forward regexp nil t)
       (catch :skip
@@ -5268,7 +5307,14 @@ the documentation of `org-diary'."
 	      category-pos (get-text-property (point) 'org-category-position)
 	      txt (org-trim
 		   (buffer-substring (match-beginning 2) (match-end 0)))
-	      tags (org-get-tags-at nil t)
+	      inherited-tags
+	      (or (eq org-agenda-show-inherited-tags 'always)
+		  (and (listp org-agenda-show-inherited-tags)
+		       (memq 'todo org-agenda-show-inherited-tags))
+		  (and (eq org-agenda-show-inherited-tags t)
+		       (or (eq org-agenda-use-tag-inheritance t)
+			   (memq 'todo org-agenda-use-tag-inheritance))))
+	      tags (org-get-tags-at nil (not inherited-tags))
 	      txt (org-agenda-format-item "" txt category tags t)
 	      priority (1+ (org-get-priority txt))
 	      todo-state (org-get-todo-state))
@@ -5395,7 +5441,8 @@ Do we have a reason to ignore this TODO entry because it has a time stamp?
 	   "\\|\\(<%%\\(([^>\n]+)\\)>\\)"))
 	 marker hdmarker deadlinep scheduledp clockp closedp inactivep
 	 donep tmp priority category category-pos ee txt timestr tags
-	 b0 b3 e3 head todo-state end-of-match show-all warntime habitp)
+	 b0 b3 e3 head todo-state end-of-match show-all warntime habitp
+	 inherited-tags)
     (goto-char (point-min))
     (while (setq end-of-match (re-search-forward regexp nil t))
       (setq b0 (match-beginning 0)
@@ -5447,7 +5494,14 @@ Do we have a reason to ignore this TODO entry because it has a time stamp?
 		     (assoc (point) deadline-position-alist))
 		(throw :skip nil))
 	    (setq hdmarker (org-agenda-new-marker)
-		  tags (org-get-tags-at nil t))
+		  inherited-tags
+		  (or (eq org-agenda-show-inherited-tags 'always)
+		      (and (listp org-agenda-show-inherited-tags)
+			   (memq 'agenda org-agenda-show-inherited-tags))
+		      (and (eq org-agenda-show-inherited-tags t)
+			   (or (eq org-agenda-use-tag-inheritance t)
+			       (memq 'agenda org-agenda-use-tag-inheritance))))
+		  tags (org-get-tags-at nil (not inherited-tags)))
 	    (looking-at "\\*+[ \t]+\\([^\r\n]+\\)")
 	    (setq head (or (match-string 1) ""))
 	    (setq txt (org-agenda-format-item
@@ -5479,7 +5533,7 @@ Do we have a reason to ignore this TODO entry because it has a time stamp?
 			      (abbreviate-file-name buffer-file-name))))
 	 (regexp "^&?%%(")
 	 marker category extra category-pos ee txt tags entry
-	 result beg b sexp sexp-entry todo-state warntime)
+	 result beg b sexp sexp-entry todo-state warntime inherited-tags)
     (goto-char (point-min))
     (while (re-search-forward regexp nil t)
       (catch :skip
@@ -5497,7 +5551,14 @@ Do we have a reason to ignore this TODO entry because it has a time stamp?
 	  (setq marker (org-agenda-new-marker beg)
 		category (org-get-category beg)
 		category-pos (get-text-property beg 'org-category-position)
-		tags (save-excursion (org-back-to-heading t) (org-get-tags-at nil t))
+		inherited-tags
+		(or (eq org-agenda-show-inherited-tags 'always)
+		    (and (listp org-agenda-show-inherited-tags)
+			 (memq 'agenda org-agenda-show-inherited-tags))
+		    (and (eq org-agenda-show-inherited-tags t)
+			 (or (eq org-agenda-use-tag-inheritance t)
+			     (memq 'agenda org-agenda-use-tag-inheritance))))
+		tags (org-get-tags-at nil (not inherited-tags))
 		todo-state (org-get-todo-state)
 		warntime (get-text-property (point) 'org-appt-warntime)
 		extra nil)
@@ -5628,7 +5689,7 @@ please use `org-class' instead."
 		    1 11))))
 	 (org-agenda-search-headline-for-time nil)
 	 marker hdmarker priority category category-pos tags closedp
-	 statep clockp state ee txt extra timestr rest clocked)
+	 statep clockp state ee txt extra timestr rest clocked inherited-tags)
     (goto-char (point-min))
     (while (re-search-forward regexp nil t)
       (catch :skip
@@ -5666,7 +5727,14 @@ please use `org-class' instead."
 	      (setq txt org-agenda-no-heading-message)
 	    (goto-char (match-beginning 0))
 	    (setq hdmarker (org-agenda-new-marker)
-		  tags (org-get-tags-at nil t))
+		  inherited-tags
+		  (or (eq org-agenda-show-inherited-tags 'always)
+		      (and (listp org-agenda-show-inherited-tags)
+			   (memq 'todo org-agenda-show-inherited-tags))
+		      (and (eq org-agenda-show-inherited-tags t)
+			   (or (eq org-agenda-use-tag-inheritance t)
+			       (memq 'todo org-agenda-use-tag-inheritance))))
+		  tags (org-get-tags-at nil (not inherited-tags)))
 	    (looking-at "\\*+[ \t]+\\([^\r\n]+\\)")
 	    (setq txt (match-string 1))
 	    (when extra
@@ -5944,7 +6012,7 @@ FRACTION is what fraction of the head-warning time has passed."
 		  deadline-results))
 	 d2 diff pos pos1 category category-pos tags donep
 	 ee txt head pastschedp todo-state face timestr s habitp show-all
-	 did-habit-check-p warntime)
+	 did-habit-check-p warntime inherited-tags)
     (goto-char (point-min))
     (while (re-search-forward regexp nil t)
       (catch :skip
@@ -6006,7 +6074,14 @@ FRACTION is what fraction of the head-warning time has passed."
 				pastschedp))
 		       (setq mm (assoc pos1 deadline-position-alist)))
 		      (throw :skip nil)))
-		(setq tags (org-get-tags-at nil t))
+		(setq inherited-tags
+		      (or (eq org-agenda-show-inherited-tags 'always)
+			  (and (listp org-agenda-show-inherited-tags)
+			       (memq 'agenda org-agenda-show-inherited-tags))
+			  (and (eq org-agenda-show-inherited-tags t)
+			       (or (eq org-agenda-use-tag-inheritance t)
+				   (memq 'agenda org-agenda-use-tag-inheritance))))
+		      tags (org-get-tags-at nil (not inherited-tags)))
 		(setq head (buffer-substring-no-properties
 			    (point)
 			    (progn (skip-chars-forward "^\r\n") (point))))
@@ -6061,7 +6136,7 @@ FRACTION is what fraction of the head-warning time has passed."
 	 (regexp org-tr-regexp)
 	 (d0 (calendar-absolute-from-gregorian date))
 	 marker hdmarker ee txt d1 d2 s1 s2 category category-pos
-	 todo-state tags pos head donep)
+	 todo-state tags pos head donep inherited-tags)
     (goto-char (point-min))
     (while (re-search-forward regexp nil t)
       (catch :skip
@@ -6087,8 +6162,15 @@ FRACTION is what fraction of the head-warning time has passed."
 		(if (not (re-search-backward org-outline-regexp-bol nil t))
 		    (setq txt org-agenda-no-heading-message)
 		  (goto-char (match-beginning 0))
-		  (setq hdmarker (org-agenda-new-marker (point)))
-		  (setq tags (org-get-tags-at nil t))
+		  (setq hdmarker (org-agenda-new-marker (point))
+			inherited-tags
+			(or (eq org-agenda-show-inherited-tags 'always)
+			    (and (listp org-agenda-show-inherited-tags)
+				 (memq 'agenda org-agenda-show-inherited-tags))
+			    (and (eq org-agenda-show-inherited-tags t)
+				 (or (eq org-agenda-use-tag-inheritance t)
+				     (memq 'agenda org-agenda-use-tag-inheritance))))
+			tags (org-get-tags-at nil (not inherited-tags)))
 		  (looking-at "\\*+[ \t]+\\([^\r\n]+\\)")
 		  (setq head (match-string 1))
 		  (let ((remove-re

lisp/org.el

@@ -13526,7 +13526,10 @@ ignore inherited ones."
 		(error nil)))))
 	(if local
 	    tags
-	  (append (org-remove-uninherited-tags org-file-tags) tags))))))
+	  (reverse (delete-dups
+		    (reverse (append
+			      (org-remove-uninherited-tags
+			       org-file-tags) tags)))))))))
 
 (defun org-add-prop-inherited (s)
   (add-text-properties 0 (length s) '(inherited t) s)