Remove `export-block' syntax type

* lisp/org-element.el (org-element-all-elements): Remove
  `export-block' type.
(org-element-block-name-alist): Make it a defconst since it is not
meant to be changed anymore.
(org-element-export-block-parser,
org-element-export-block-interpreter): Remove functions.

* lisp/ox.el (org-export-filters-alist): Remove export block filter.
(org-export-register-backend): Do not alter
`org-export-block-name-alist' anymore.
(org-export-define-backend, org-export-define-derived-backend): Update
docstring.
(org-export-filter-export-block-functions): Remove variable.

* testing/lisp/test-org-element.el (test-org-element/export-block-parser,
  test-org-element/export-block-interpreter): Remove tests.

* testing/lisp/test-ox.el (test-org-export/define-backend): Update test.

lisp/org-element.el

@@ -45,11 +45,11 @@
 ;; and `special-block'.
 ;;
 ;; Other element types are: `babel-call', `clock', `comment',
-;; `comment-block', `diary-sexp', `example-block', `export-block',
-;; `fixed-width', `horizontal-rule', `keyword', `latex-environment',
-;; `node-property', `paragraph', `planning', `src-block', `table',
-;; `table-row' and `verse-block'.  Among them, `paragraph' and
-;; `verse-block' types can contain Org objects and plain text.
+;; `comment-block', `diary-sexp', `example-block', `fixed-width',
+;; `horizontal-rule', `keyword', `latex-environment', `node-property',
+;; `paragraph', `planning', `src-block', `table', `table-row' and
+;; `verse-block'.  Among them, `paragraph' and `verse-block' types can
+;; contain Org objects and plain text.
 ;;
 ;; Objects are related to document's contents.  Some of them are
 ;; recursive.  Associated types are of the following: `bold', `code',
@@ -173,11 +173,11 @@ is not sufficient to know if point is at a paragraph ending.  See
 
 (defconst org-element-all-elements
   '(babel-call center-block clock comment comment-block diary-sexp drawer
-	       dynamic-block example-block export-block fixed-width
-	       footnote-definition headline horizontal-rule inlinetask item
-	       keyword latex-environment node-property paragraph plain-list
-	       planning property-drawer quote-block section
-	       special-block src-block table table-row verse-block)
+	       dynamic-block example-block fixed-width footnote-definition
+	       headline horizontal-rule inlinetask item keyword
+	       latex-environment node-property paragraph plain-list
+	       planning property-drawer quote-block section special-block
+	       src-block table table-row verse-block)
   "Complete list of element types.")
 
 (defconst org-element-greater-elements
@@ -198,7 +198,7 @@ is not sufficient to know if point is at a paragraph ending.  See
 	 superscript table-cell underline)
   "List of recursive object types.")
 
-(defvar org-element-block-name-alist
+(defconst org-element-block-name-alist
   '(("CENTER" . org-element-center-block-parser)
     ("COMMENT" . org-element-comment-block-parser)
     ("EXAMPLE" . org-element-example-block-parser)
@@ -1899,60 +1899,6 @@ CONTENTS is nil."
 	    "#+END_EXAMPLE")))
 
 
-;;;; Export Block
-
-(defun org-element-export-block-parser (limit affiliated)
-  "Parse an export block.
-
-LIMIT bounds the search.  AFFILIATED is a list of which CAR is
-the buffer position at the beginning of the first affiliated
-keyword and CDR is a plist of affiliated keywords along with
-their value.
-
-Return a list whose CAR is `export-block' and CDR is a plist
-containing `:begin', `:end', `:type', `:value', `:post-blank' and
-`:post-affiliated' keywords.
-
-Assume point is at export-block beginning."
-  (let* ((case-fold-search t)
-	 (type (progn (looking-at "[ \t]*#\\+BEGIN_\\(\\S-+\\)")
-		      (upcase (org-match-string-no-properties 1)))))
-    (if (not (save-excursion
-	       (re-search-forward
-		(format "^[ \t]*#\\+END_%s[ \t]*$" type) limit t)))
-	;; Incomplete block: parse it as a paragraph.
-	(org-element-paragraph-parser limit affiliated)
-      (let ((contents-end (match-beginning 0)))
-	(save-excursion
-	  (let* ((begin (car affiliated))
-		 (post-affiliated (point))
-		 (contents-begin (progn (forward-line) (point)))
-		 (pos-before-blank (progn (goto-char contents-end)
-					  (forward-line)
-					  (point)))
-		 (end (progn (skip-chars-forward " \r\t\n" limit)
-			     (if (eobp) (point) (line-beginning-position))))
-		 (value (buffer-substring-no-properties contents-begin
-							contents-end)))
-	    (list 'export-block
-		  (nconc
-		   (list :begin begin
-			 :end end
-			 :type type
-			 :value value
-			 :post-blank (count-lines pos-before-blank end)
-			 :post-affiliated post-affiliated)
-		   (cdr affiliated)))))))))
-
-(defun org-element-export-block-interpreter (export-block contents)
-  "Interpret EXPORT-BLOCK element as Org syntax.
-CONTENTS is nil."
-  (let ((type (org-element-property :type export-block)))
-    (concat (format "#+BEGIN_%s\n" type)
-	    (org-element-property :value export-block)
-	    (format "#+END_%s" type))))
-
-
 ;;;; Fixed-width
 
 (defun org-element-fixed-width-parser (limit affiliated)

lisp/ox.el

@@ -188,7 +188,6 @@ way they are handled must be hard-coded into
     (:filter-dynamic-block . org-export-filter-dynamic-block-functions)
     (:filter-entity . org-export-filter-entity-functions)
     (:filter-example-block . org-export-filter-example-block-functions)
-    (:filter-export-block . org-export-filter-export-block-functions)
     (:filter-export-snippet . org-export-filter-export-snippet-functions)
     (:filter-final-output . org-export-filter-final-output-functions)
     (:filter-fixed-width . org-export-filter-fixed-width-functions)
@@ -935,10 +934,6 @@ BACKEND is a structure with `org-export-backend' type."
   (let ((parent (org-export-backend-parent backend)))
     (when (and parent (not (org-export-get-backend parent)))
       (error "Cannot use unknown \"%s\" back-end as a parent" parent)))
-  ;; Register dedicated export blocks in the parser.
-  (dolist (name (org-export-backend-blocks backend))
-    (add-to-list 'org-element-block-name-alist
-		 (cons name 'org-element-export-block-parser)))
   ;; If a back-end with the same name as BACKEND is already
   ;; registered, replace it with BACKEND.  Otherwise, simply add
   ;; BACKEND to the list of registered back-ends.
@@ -1070,7 +1065,7 @@ keywords are understood:
     String, or list of strings, representing block names that
     will not be parsed.  This is used to specify blocks that will
     contain raw code specific to the back-end.  These blocks
-    still have to be handled by the relative `export-block' type
+    still have to be handled by the `special-block' type
     translator.
 
   :filters-alist
@@ -1174,7 +1169,7 @@ keywords are understood:
     String, or list of strings, representing block names that
     will not be parsed.  This is used to specify blocks that will
     contain raw code specific to the back-end.  These blocks
-    still have to be handled by the relative `export-block' type
+    still have to be handled by the `special-block' type
     translator.
 
   :filters-alist
@@ -2593,12 +2588,6 @@ Each filter is called with three arguments: the transcoded data,
 as a string, the back-end, as a symbol, and the communication
 channel, as a plist.  It must return a string or nil.")
 
-(defvar org-export-filter-export-block-functions nil
-  "List of functions applied to a transcoded export-block.
-Each filter is called with three arguments: the transcoded data,
-as a string, the back-end, as a symbol, and the communication
-channel, as a plist.  It must return a string or nil.")
-
 (defvar org-export-filter-fixed-width-functions nil
   "List of functions applied to a transcoded fixed-width.
 Each filter is called with three arguments: the transcoded data,

testing/lisp/test-org-element.el

@@ -777,39 +777,6 @@ Some other text
 	(org-element-property :label-fmt (org-element-at-point)))))))
 
 
-;;;; Export Block
-
-(ert-deftest test-org-element/export-block-parser ()
-  "Test `export-block' parser."
-  ;; Standard test.
-  (should
-   (org-test-with-temp-text "#+BEGIN_LATEX\nText\n#+END_LATEX"
-     (org-element-map
-      (let ((org-element-block-name-alist
-	     '(("LATEX" . org-element-export-block-parser))))
-	(org-element-parse-buffer))
-      'export-block 'identity)))
-  ;; Ignore case.
-  (should
-   (let ((org-element-block-name-alist
-	  '(("LATEX" . org-element-export-block-parser))))
-     (org-test-with-temp-text "#+begin_latex\nText\n#+end_latex"
-       (org-element-map (org-element-parse-buffer) 'export-block 'identity))))
-  ;; Ignore incomplete block.
-  (should-not
-   (let ((org-element-block-name-alist
-	  '(("LATEX" . org-element-export-block-parser))))
-     (org-test-with-temp-text "#+BEGIN_LATEX"
-       (org-element-map (org-element-parse-buffer) 'export-block
-	 'identity nil t))))
-  ;; Handle non-empty blank line at the end of buffer.
-  (should
-   (let ((org-element-block-name-alist
-	  '(("LATEX" . org-element-export-block-parser))))
-     (org-test-with-temp-text "#+BEGIN_LATEX\nC\n#+END_LATEX\n "
-       (= (org-element-property :end (org-element-at-point)) (point-max))))))
-
-
 ;;;; Export Snippet
 
 (ert-deftest test-org-element/export-snippet-parser ()
@@ -2432,12 +2399,6 @@ CLOCK: [2012-01-01 sun. 00:01]--[2012-01-01 sun. 00:02] =>  0:01"))))
 	   "#+BEGIN_EXAMPLE\n,* Headline\n ,#+keyword\nText #+END_EXAMPLE")
 	  "#+BEGIN_EXAMPLE\n,* Headline\n ,#+keyword\nText #+END_EXAMPLE\n")))
 
-(ert-deftest test-org-element/export-block-interpreter ()
-  "Test export block interpreter."
-  (should (equal (org-test-parse-and-interpret
-		  "#+BEGIN_HTML\nTest\n#+END_HTML")
-		 "#+BEGIN_HTML\nTest\n#+END_HTML\n")))
-
 (ert-deftest test-org-element/fixed-width-interpreter ()
   "Test fixed width interpreter."
   ;; Standard test.

testing/lisp/test-ox.el

@@ -1118,15 +1118,7 @@ Footnotes[fn:1], [fn:test] and [fn:inline:anonymous footnote].
 	    (org-export-define-backend 'test
 	      '((headline . my-headline-test))
 	      :menu-entry '(?k "Test Export" test))
-	    (org-export-backend-menu (org-export-get-backend 'test)))))
-  ;; Export Blocks.
-  (should
-   (equal '(("TEST" . org-element-export-block-parser))
-	  (let (org-export--registered-backends org-element-block-name-alist)
-	    (org-export-define-backend 'test
-	      '((headline . my-headline-test))
-	      :export-block '("test"))
-	    org-element-block-name-alist))))
+	    (org-export-backend-menu (org-export-get-backend 'test))))))
 
 (ert-deftest test-org-export/define-derived-backend ()
   "Test `org-export-define-derived-backend' specifications."