lisp/org-element: Add a parameters-line property to special blocks

Add a property `:parameters' to special blocks, to store the
PARAMETERS as a string.

* lisp/org-element.el (org-element-special-block-parser): Parse
PARAMETERS and set the property `:parameters'.

(org-element-special-block-interpreter): Interpret the property
`:parameters'.

*
testing/lisp/test-org-element.el (test-org-element/special-block-parser):
Add a new test for PARAMETERS.

(test-org-element/special-block-interpreter): Add new tests for PARAMETERS.

lisp/org-element.el

@@ -1868,13 +1868,15 @@ keyword and CDR is a plist of affiliated keywords along with
 their value.
 
 Return a list whose CAR is `special-block' and CDR is a plist
-containing `:type', `:begin', `:end', `:contents-begin',
-`:contents-end', `:post-blank' and `:post-affiliated' keywords.
+containing `:type', `:parameters', `:begin', `:end',
+`:contents-begin', `:contents-end', `:post-blank' and
+`:post-affiliated' keywords.
 
 Assume point is at the beginning of the block."
   (let* ((case-fold-search t)
-	 (type (progn (looking-at "[ \t]*#\\+BEGIN_\\(\\S-+\\)")
-		      (match-string-no-properties 1))))
+	 (type (progn (looking-at "[ \t]*#\\+BEGIN_\\(\\S-+\\)[ \t]*\\(.*\\)[ \t]*$")
+		      (match-string-no-properties 1)))
+	 (parameters (match-string-no-properties 2)))
     (if (not (save-excursion
 	       (re-search-forward
 		(format "^[ \t]*#\\+END_%s[ \t]*$" (regexp-quote type))
@@ -1898,6 +1900,8 @@ Assume point is at the beginning of the block."
 	    (list 'special-block
 		  (nconc
 		   (list :type type
+			 :parameters (and (org-string-nw-p parameters)
+					  (org-trim parameters))
 			 :begin begin
 			 :end end
 			 :contents-begin contents-begin
@@ -1909,8 +1913,11 @@ Assume point is at the beginning of the block."
 (defun org-element-special-block-interpreter (special-block contents)
   "Interpret SPECIAL-BLOCK element as Org syntax.
 CONTENTS is the contents of the element."
-  (let ((block-type (org-element-property :type special-block)))
-    (format "#+begin_%s\n%s#+end_%s" block-type (or contents "") block-type)))
+  (let ((block-type (org-element-property :type special-block))
+        (parameters (org-element-property :parameters special-block)))
+    (format "#+begin_%s%s\n%s#+end_%s" block-type
+            (if parameters (concat " " parameters) "")
+            (or contents "") block-type)))
 
 
 

testing/lisp/test-org-element.el

@@ -2429,7 +2429,19 @@ Outside list"
   ;; When contents is empty, the parsed contents is nil.
   (should
    (org-test-with-temp-text "#+BEGIN_SPECIAL\n#+END_SPECIAL"
-     (eq nil (org-element-contents (org-element-at-point))))))
+     (eq nil (org-element-contents (org-element-at-point)))))
+  ;; Parse parameters if any, trimming blanks.
+  (should
+   (org-test-with-temp-text "#+BEGIN_SPECIAL* s  p   :w 3   \nContent.\n#+END_SPECIAL*"
+     (equal "s  p   :w 3"
+	    (org-element-property :parameters (org-element-at-point)))))
+  ;; When parameters is blank, `:parameters' is nil.
+  (should
+   (org-test-with-temp-text "#+BEGIN_SPECIAL*     \t   \nContent.\n#+END_SPECIAL*"
+     (eq nil (org-element-property :parameters (org-element-at-point))))
+   ))
+
+
 
 
 ;;;; Src Block
@@ -2945,13 +2957,30 @@ Outside list"
 
 (ert-deftest test-org-element/special-block-interpreter ()
   "Test special block interpreter."
+  ;; No parameters
   (should (equal (org-test-parse-and-interpret
 		  "#+BEGIN_SPECIAL\nTest\n#+END_SPECIAL")
 		 "#+begin_SPECIAL\nTest\n#+end_SPECIAL\n"))
   ;; No content
   (should (equal (org-test-parse-and-interpret
 		  "#+BEGIN_SPECIAL\n#+END_SPECIAL")
-		 "#+begin_SPECIAL\n#+end_SPECIAL\n")))
+		 "#+begin_SPECIAL\n#+end_SPECIAL\n"))
+  ;; Some parameters
+  (should
+   (equal (org-test-parse-and-interpret
+           "#+BEGIN_special some parameters until EOL\nA very special content\n#+END_special")
+          "#+begin_special some parameters until EOL\nA very special content\n#+end_special\n"))
+  ;; No parameters (blanks only)
+  (should
+   (equal (org-test-parse-and-interpret
+           "#+BEGIN_special   \t \nA very special content\n#+END_special")
+          "#+begin_special\nA very special content\n#+end_special\n"))
+  ;; Some parameters with leading and trailing blanks, no content, and
+  ;; a /special/ name.
+  (should
+   (equal (org-test-parse-and-interpret
+           "#+BEGIN_spe<c>ial  :a  :b \t  :c  \t \n#+END_spe<c>ial")
+          "#+begin_spe<c>ial :a  :b \t  :c\n#+end_spe<c>ial\n")))
 
 (ert-deftest test-org-element/babel-call-interpreter ()
   "Test Babel call interpreter."