org-capture: Expand interactive placeholders last

* lisp/org-capture.el (org-capture-templates): Update docstring.
(org-capture-fill-template): Expand interactive placeholders when the
template is otherwise completely filled.

This restores the previous behaviour for template's expansion.

lisp/org-capture.el

@@ -231,8 +231,8 @@ be replaced with content and expanded:
   %(sexp)     Evaluate elisp `(sexp)' and replace it with the results.
               Only placeholders pre-existing within the template, or
               introduced with %[pathname] are expanded this way.  Since this
-              happens very late in the process, other %-escapes can be used to
+              happens after expanding non-interactive %-escapes, those can
-              fill the expression.
+              be used to fill the expression.
   %<...>      The result of format-time-string on the ... format specification.
   %t          Time stamp, date only.
   %T          Time stamp with date and time.
@@ -261,9 +261,8 @@ be replaced with content and expanded:
               A default value and a completion table ca be specified like this:
               %^{prompt|default|completion2|completion3|...}.
   %?          After completing the template, position cursor here.
-  %number     Insert the text entered at the nth %^{prompt}, where `number' is a
+  %\\N         Insert the text entered at the nth %^{prompt}, where N
-              number, starting from 1.  These placeholders are expanded as the
+              is a number, starting from 1.
-              last step of the process.
 
 Apart from these general escapes, you can access information specific to
 the link type that is created.  For example, calling `org-capture' in emails
@@ -1604,7 +1603,6 @@ The template may still contain \"%?\" for cursor positioning."
       (erase-buffer)
       ;; Turn on org-mode in temp buffer, set local variables.  This
       ;; is to support completion in interactive prompts
-      (let ((org-inhibit-startup t)) (org-mode))
       (insert template)
       (goto-char (point-min))
       (org-capture-steal-local-variables buffer)
@@ -1629,16 +1627,14 @@ The template may still contain \"%?\" for cursor positioning."
       ;; Mark %() embedded elisp for later evaluation.
       (org-capture--expand-embedded-elisp 'mark)
 
-      (let ((regexp "%\\(:[-a-za-z]+\\|<\\([^>\n]+\\)>\\|[aAcfFikKlntTuUx]\\|\
+      ;; Expand non-interactive templates.
-\\^\\(?:{\\([^}]*\\)}\\)?\\([CgGLptTuU]\\)?\\)")
+      (let ((regexp "%\\(:[-a-za-z]+\\|<\\([^>\n]+\\)>\\|[aAcfFikKlntTuUx]\\)"))
-	    (strings))
+	(save-excursion
 	  (while (re-search-forward regexp nil t)
 	    (let ((pos (copy-marker (match-beginning 0)))
 		  (end (copy-marker (match-end 0)))
 		  (value (match-string 1))
-		(time-string (match-string 2))
+		  (time-string (match-string 2)))
-		(prompt (match-string-no-properties 3))
-		(key (match-string 4)))
 	      (unless (org-capture-escaped-%)
 		(goto-char pos)
 		(delete-region pos end)
@@ -1655,20 +1651,47 @@ The template may still contain \"%?\" for cursor positioning."
 			(insert (mapconcat #'identity
 					   (split-string initial "\n")
 					   (concat "\n" lead)))))
-		(?^
+		  (?a (insert v-a))
-		 ;; Interactive template entries.
+		  (?A (insert v-A))
-		 (let ((completions nil)
+		  (?c (insert v-c))
-		       (default nil)
+		  (?f (insert v-f))
-		       (histvar nil))
+		  (?F (insert v-F))
-		   (when prompt
+		  (?k (insert v-k))
-		     (setq completions (org-split-string prompt "|"))
+		  (?K (insert v-K))
-		     (setq prompt (pop completions))
+		  (?l (insert v-l))
-		     (setq default (car completions))
+		  (?t (insert v-t))
-		     (setq histvar
+		  (?T (insert v-T))
-			   (intern (concat
+		  (?u (insert v-u))
-				    "org-capture-template-prompt-history::"
+		  (?U (insert v-U))
+		  (?x (insert v-x)))
+		(set-marker pos nil)
+		(set-marker end nil))))))
+
+      ;; Expand %() embedded Elisp.  Limit to Sexp originally marked.
+      (org-capture--expand-embedded-elisp)
+
+      ;; Expand interactive templates.  This is the last step so that
+      ;; template is mostly expanded when prompting happens.
+      (let ((org-inhibit-startup t)) (org-mode))
+      (let (strings)			; Stores interactive answers.
+	(save-excursion
+	  (let ((regexp "%\\^\\(?:{\\([^}]*\\)}\\)?\\([CgGLptTuU]\\)?"))
+	    (while (re-search-forward regexp nil t)
+	      (unless (org-capture-escaped-%)
+		(let* ((items
+			(and (match-end 1)
+			     (save-match-data
+			       (split-string (match-string-no-properties 1)
+					     "|"))))
+		       (prompt (nth 0 items))
+		       (default (nth 1 items))
+		       (completions (nthcdr 2 items))
+		       (histvar
+			(intern
+			 (concat "org-capture-template-prompt-history::"
 				 (or prompt ""))))
-		     (setq completions (mapcar #'list completions)))
+		       (key (match-string 2)))
+		  (delete-region (match-beginning 0) (match-end 0))
 		  (pcase key
 		    ((or `"G" `"g")
 		     (let* ((org-last-tags-completion-table
@@ -1729,22 +1752,7 @@ The template may still contain \"%?\" for cursor positioning."
 				    ": ")
 			    completions nil nil nil histvar default)
 			   strings)
-		      (insert (car strings))))))
+		     (insert (car strings)))))))))
-		(?a (insert v-a))
-		(?A (insert v-A))
-		(?c (insert v-c))
-		(?f (insert v-f))
-		(?F (insert v-F))
-		(?k (insert v-k))
-		(?K (insert v-K))
-		(?l (insert v-l))
-		(?t (insert v-t))
-		(?T (insert v-T))
-		(?u (insert v-u))
-		(?U (insert v-U))
-		(?x (insert v-x)))
-	      (set-marker pos nil)
-	      (set-marker end nil)))))
 
 	;; Replace %n escapes with nth %^{...} string.
 	(setq strings (nreverse strings))
@@ -1753,16 +1761,17 @@ The template may still contain \"%?\" for cursor positioning."
 	    (unless (org-capture-escaped-%)
 	      (replace-match
 	       (nth (1- (string-to-number (match-string 1))) strings)
-	     nil t))))
+	       nil t)))))
-
-      ;; Expand %() embedded Elisp.  Limit to Sexp originally marked.
-      (org-capture--expand-embedded-elisp)
 
       ;; Make sure there are no empty lines before the text, and that
       ;; it ends with a newline character.
-      (goto-char (point-min))
+      (skip-chars-forward " \t\n")
-      (while (looking-at "[ \t]*\n") (replace-match ""))
+      (delete-region (point-min) (line-beginning-position))
-      (when (re-search-forward "[ \t\n]*\\'" nil t) (replace-match "\n"))
+      (goto-char (point-max))
+      (skip-chars-backward " \t\n")
+      (delete-region (point) (point-max))
+      (insert "\n")
+
       ;; Return the expanded template and kill the temporary buffer.
       (untabify (point-min) (point-max))
       (set-buffer-modified-p nil)