ob-ref: Properly resolve references in ":post" arguments

* lisp/ob-core.el (org-babel-exp-reference-buffer): New variable, as
  a replacement for `org-current-export-file'.
(org-babel-check-confirm-evaluate): Use new variable.
* lisp/ob-exp.el (org-babel-exp-in-export-file): Use new variable.
(org-babel-exp-get-export-buffer): Remove function.
(org-babel-exp-process-buffer): Change signature.
* lisp/ob-ref.el (org-babel-ref-resolve): Use new variable during
  export in order to properly resolve references.
* lisp/ox.el (org-export-execute-babel-code): Use new variable.

* contrib/lisp/org-wikinodes.el (org-wikinodes-process-links-for-export):
  Remove a cond branch as it is always
  false (`org-current-export-file' couldn't be a string).

* testing/lisp/test-ob-lob.el (test-ob-lob/export-lob-lines): Update
  test.
* testing/lisp/test-ob.el (test-ob/eval-header-argument): Update test.
* testing/lisp/test-ob-exp.el (ob-export/reference-in-post-header):
  New test.

During export, Babel executes sequentially all blocks in the buffer
being exported.  This can lead to modifications preventing some
references from being resolved.  As a workaround, Babel stores
a pristine copy of the buffer in a variable so it can always find
needed references.

Before this patch, the variable storing this copy was
`org-current-export-file' and was dynamically bound in "ox.el".  It
was used to resolve noweb references (`org-babel-expand-noweb-references')
but not regular references (`org-babel-ref-resolve').

Now, the variable is `org-babel-exp-reference-buffer' and it is bound
from `org-babel-exp-process-buffer'.  It is used to resolve all
references.  In particular, this allows to use references in :post
header.

Thanks to Jarmo Hurri for reporting it.

8 files changed, 134 insertions, 129 deletions

diff --git a/contrib/lisp/org-wikinodes.el b/contrib/lisp/org-wikinodes.el
index 7d136c2..7f3e2e3 100644
--- a/contrib/lisp/org-wikinodes.el
+++ b/contrib/lisp/org-wikinodes.el
@@ -268,7 +268,6 @@ If there is no such wiki target, return nil."
 		    (car org-export-target-aliases))))
       (push (caar target-alist) (cdr a)))))
 
-(defvar org-current-export-file)
 (defun org-wikinodes-process-links-for-export ()
   "Process Wiki links in the export preprocess buffer.
 
@@ -294,12 +293,6 @@ with working links."
 	   ((eq org-wikinodes-scope 'file)
 	    ;; No match in file, and other files are not allowed
 	    (insert (format "%s" link)))
-	   ((setq file
-		  (and (org-string-nw-p org-current-export-file)
-		       (org-wikinodes-which-file
-			link (file-name-directory org-current-export-file))))
-	    ;; Match in another file in the current directory
-	    (insert (format "[[file:%s::%s][%s]]" file link link)))
 	   (t ;; No match for this link
 	    (insert (format "%s" link)))))))))
 
diff --git a/lisp/ob-core.el b/lisp/ob-core.el
index 8c55a18..0adfc33 100644
--- a/lisp/ob-core.el
+++ b/lisp/ob-core.el
@@ -285,7 +285,11 @@ Returns a list
       (setf (nth 2 info) (org-babel-process-params (nth 2 info))))
     (when info (append info (list name indent head)))))
 
-(defvar org-current-export-file) ; dynamically bound
+(defvar org-babel-exp-reference-buffer nil
+  "Buffer containing original contents of the exported buffer.
+This is used by Babel to resolve references in source blocks.
+Its value is dynamically bound during export.")
+
 (defmacro org-babel-check-confirm-evaluate (info &rest body)
   "Evaluate BODY with special execution confirmation variables set.
 
@@ -305,7 +309,7 @@ name of the code block."
 				 (when (assoc :noeval ,headers) "no")))
 	    (,eval-no        (or (equal ,eval "no")
 				 (equal ,eval "never")))
-	    (,export         (org-bound-and-true-p org-current-export-file))
+	    (,export         org-babel-exp-reference-buffer)
 	    (,eval-no-export (and ,export (or (equal ,eval "no-export")
 					      (equal ,eval "never-export"))))
 	    (noeval          (or ,eval-no ,eval-no-export))
diff --git a/lisp/ob-exp.el b/lisp/ob-exp.el
index 38618ee..0ddb4dc 100644
--- a/lisp/ob-exp.el
+++ b/lisp/ob-exp.el
@@ -27,7 +27,6 @@
 (eval-when-compile
   (require 'cl))
 
-(defvar org-current-export-file)
 (defvar org-babel-lob-one-liner-regexp)
 (defvar org-babel-ref-split-regexp)
 (defvar org-list-forbidden-blocks)
@@ -61,27 +60,18 @@ be executed."
 		 (const :tag "Always" t)))
 (put 'org-export-babel-evaluate 'safe-local-variable (lambda (x) (eq x nil)))
 
-(defun org-babel-exp-get-export-buffer ()
-  "Return the current export buffer if possible."
-  (cond
-   ((bufferp org-current-export-file) org-current-export-file)
-   (org-current-export-file (get-file-buffer org-current-export-file))
-   ('otherwise
-    (error "Requested export buffer when `org-current-export-file' is nil"))))
-
 (defvar org-link-search-inhibit-query)
-
 (defmacro org-babel-exp-in-export-file (lang &rest body)
   (declare (indent 1))
   `(let* ((lang-headers (intern (concat "org-babel-default-header-args:" ,lang)))
 	  (heading (nth 4 (ignore-errors (org-heading-components))))
 	  (export-buffer (current-buffer))
-	  (original-buffer (org-babel-exp-get-export-buffer)) results)
-     (when original-buffer
-       ;; resolve parameters in the original file so that
-       ;; headline and file-wide parameters are included, attempt
-       ;; to go to the same heading in the original file
-       (set-buffer original-buffer)
+	  results)
+     (when org-babel-exp-reference-buffer
+       ;; Resolve parameters in the original file so that headline and
+       ;; file-wide parameters are included, attempt to go to the same
+       ;; heading in the original file
+       (set-buffer org-babel-exp-reference-buffer)
        (save-restriction
 	 (when heading
 	   (condition-case nil
@@ -152,12 +142,17 @@ this template."
   :type 'string)
 
 (defvar org-babel-default-lob-header-args)
-(defun org-babel-exp-process-buffer ()
-  "Execute all Babel blocks in current buffer."
+(defun org-babel-exp-process-buffer (reference-buffer)
+  "Execute all Babel blocks in current buffer.
+REFERENCE-BUFFER is the buffer containing a pristine copy of the
+buffer being processed.  It is used to properly resolve
+references in source blocks, as modifications in current buffer
+may make them unreachable."
   (interactive)
   (save-window-excursion
     (save-excursion
       (let ((case-fold-search t)
+	    (org-babel-exp-reference-buffer reference-buffer)
 	    (regexp (concat org-babel-inline-src-block-regexp "\\|"
 			    org-babel-lob-one-liner-regexp "\\|"
 			    "^[ \t]*#\\+BEGIN_SRC")))
@@ -186,7 +181,7 @@ this template."
 			 (if (and (cdr (assoc :noweb params))
 				  (string= "yes" (cdr (assoc :noweb params))))
 			     (org-babel-expand-noweb-references
-			      info (org-babel-exp-get-export-buffer))
+			      info org-babel-exp-reference-buffer)
 			   (nth 1 info)))
 		   (goto-char begin)
 		   (let ((replacement (org-babel-exp-do-export info 'inline)))
@@ -342,7 +337,7 @@ replaced with its value."
 	     (org-babel-noweb-wrap) "" (nth 1 info))
 	  (if (org-babel-noweb-p (nth 2 info) :export)
 	      (org-babel-expand-noweb-references
-	       info (org-babel-exp-get-export-buffer))
+	       info org-babel-exp-reference-buffer)
 	    (nth 1 info))))
   (org-fill-template
    org-babel-exp-code-template
@@ -371,7 +366,7 @@ inhibit insertion of results into the buffer."
     (let ((lang (nth 0 info))
 	  (body (if (org-babel-noweb-p (nth 2 info) :eval)
 		    (org-babel-expand-noweb-references
-		     info (org-babel-exp-get-export-buffer))
+		     info org-babel-exp-reference-buffer)
 		  (nth 1 info)))
 	  (info (copy-sequence info))
 	  (org-babel-current-src-block-location (point-marker)))
diff --git a/lisp/ob-ref.el b/lisp/ob-ref.el
index f50ca72..6172895 100644
--- a/lisp/ob-ref.el
+++ b/lisp/ob-ref.el
@@ -129,98 +129,99 @@ the variable."
 (defun org-babel-ref-resolve (ref)
   "Resolve the reference REF and return its value."
   (save-window-excursion
-    (save-excursion
-      (let ((case-fold-search t)
-	    type args new-refere new-header-args new-referent result
-	    lob-info split-file split-ref index index-row index-col id)
-	;; if ref is indexed grab the indices -- beware nested indices
-	(when (and (string-match "\\[\\([^\\[]+\\)\\]$" ref)
-		   (let ((str (substring ref 0 (match-beginning 0))))
-		     (= (org-count ?( str) (org-count ?) str))))
-	  (setq index (match-string 1 ref))
-	  (setq ref (substring ref 0 (match-beginning 0))))
-	;; assign any arguments to pass to source block
-	(when (string-match
-	       "^\\(.+?\\)\\(\\[\\(.*\\)\\]\\|\\(\\)\\)\(\\(.*\\)\)$" ref)
-	  (setq new-refere      (match-string 1 ref))
-	  (setq new-header-args (match-string 3 ref))
-	  (setq new-referent    (match-string 5 ref))
-	  (when (> (length new-refere) 0)
-	    (when (> (length new-referent) 0)
-	      (setq args (mapcar (lambda (ref) (cons :var ref))
-				 (org-babel-ref-split-args new-referent))))
-	    (when (> (length new-header-args) 0)
-	      (setq args (append (org-babel-parse-header-arguments
-				  new-header-args) args)))
-	    (setq ref new-refere)))
-	(when (string-match "^\\(.+\\):\\(.+\\)$" ref)
-	  (setq split-file (match-string 1 ref))
-	  (setq split-ref (match-string 2 ref))
-	  (find-file split-file) (setq ref split-ref))
-	(save-restriction
-	  (widen)
-	  (goto-char (point-min))
-	  (if (let ((src-rx (org-babel-named-src-block-regexp-for-name ref))
-		    (res-rx (org-babel-named-data-regexp-for-name ref)))
-		;; goto ref in the current buffer
-		(or
-		 ;; check for code blocks
-		 (re-search-forward src-rx nil t)
-		 ;; check for named data
-		 (re-search-forward res-rx nil t)
-		 ;; check for local or global headlines by id
-		 (setq id (org-babel-ref-goto-headline-id ref))
-		 ;; check the Library of Babel
-		 (setq lob-info (cdr (assoc (intern ref)
-					    org-babel-library-of-babel)))))
-	      (unless (or lob-info id) (goto-char (match-beginning 0)))
-	    ;; ;; TODO: allow searching for names in other buffers
-	    ;; (setq id-loc (org-id-find ref 'marker)
-	    ;;       buffer (marker-buffer id-loc)
-	    ;;       loc (marker-position id-loc))
-	    ;; (move-marker id-loc nil)
-	    (error "Reference '%s' not found in this buffer" ref))
-	  (cond
-	   (lob-info (setq type 'lob))
-	   (id (setq type 'id))
-	   ((and (looking-at org-babel-src-name-regexp)
-		 (save-excursion
-		   (forward-line 1)
-		   (or (looking-at org-babel-src-block-regexp)
-		       (looking-at org-babel-multi-line-header-regexp))))
-	    (setq type 'source-block))
-	   ((and (looking-at org-babel-src-name-regexp)
-		 (save-excursion
-		   (forward-line 1)
-		   (looking-at org-babel-lob-one-liner-regexp)))
-	    (setq type 'call-line))
-	   (t (while (not (setq type (org-babel-ref-at-ref-p)))
-		(forward-line 1)
-		(beginning-of-line)
-		(if (or (= (point) (point-min)) (= (point) (point-max)))
-		    (error "Reference not found")))))
-	  (let ((params (append args '((:results . "silent")))))
-	    (setq result
-		  (case type
-		    (results-line (org-babel-read-result))
-		    (table        (org-babel-read-table))
-		    (list         (org-babel-read-list))
-		    (file         (org-babel-read-link))
-		    (source-block (org-babel-execute-src-block
-				   nil nil (if org-babel-update-intermediate
-					       nil params)))
-		    (call-line (save-excursion
-				 (forward-line 1)
-				 (org-babel-lob-execute
-				  (org-babel-lob-get-info))))
-		    (lob          (org-babel-execute-src-block
-				   nil lob-info params))
-		    (id           (org-babel-ref-headline-body)))))
-	  (if (symbolp result)
-	      (format "%S" result)
-	    (if (and index (listp result))
-		(org-babel-ref-index-list index result)
-	      result)))))))
+    (with-current-buffer (or org-babel-exp-reference-buffer (current-buffer))
+      (save-excursion
+	(let ((case-fold-search t)
+	      type args new-refere new-header-args new-referent result
+	      lob-info split-file split-ref index index-row index-col id)
+	  ;; if ref is indexed grab the indices -- beware nested indices
+	  (when (and (string-match "\\[\\([^\\[]+\\)\\]$" ref)
+		     (let ((str (substring ref 0 (match-beginning 0))))
+		       (= (org-count ?( str) (org-count ?) str))))
+	    (setq index (match-string 1 ref))
+	    (setq ref (substring ref 0 (match-beginning 0))))
+	  ;; assign any arguments to pass to source block
+	  (when (string-match
+		 "^\\(.+?\\)\\(\\[\\(.*\\)\\]\\|\\(\\)\\)\(\\(.*\\)\)$" ref)
+	    (setq new-refere      (match-string 1 ref))
+	    (setq new-header-args (match-string 3 ref))
+	    (setq new-referent    (match-string 5 ref))
+	    (when (> (length new-refere) 0)
+	      (when (> (length new-referent) 0)
+		(setq args (mapcar (lambda (ref) (cons :var ref))
+				   (org-babel-ref-split-args new-referent))))
+	      (when (> (length new-header-args) 0)
+		(setq args (append (org-babel-parse-header-arguments
+				    new-header-args) args)))
+	      (setq ref new-refere)))
+	  (when (string-match "^\\(.+\\):\\(.+\\)$" ref)
+	    (setq split-file (match-string 1 ref))
+	    (setq split-ref (match-string 2 ref))
+	    (find-file split-file) (setq ref split-ref))
+	  (save-restriction
+	    (widen)
+	    (goto-char (point-min))
+	    (if (let ((src-rx (org-babel-named-src-block-regexp-for-name ref))
+		      (res-rx (org-babel-named-data-regexp-for-name ref)))
+		  ;; goto ref in the current buffer
+		  (or
+		   ;; check for code blocks
+		   (re-search-forward src-rx nil t)
+		   ;; check for named data
+		   (re-search-forward res-rx nil t)
+		   ;; check for local or global headlines by id
+		   (setq id (org-babel-ref-goto-headline-id ref))
+		   ;; check the Library of Babel
+		   (setq lob-info (cdr (assoc (intern ref)
+					      org-babel-library-of-babel)))))
+		(unless (or lob-info id) (goto-char (match-beginning 0)))
+	      ;; ;; TODO: allow searching for names in other buffers
+	      ;; (setq id-loc (org-id-find ref 'marker)
+	      ;;       buffer (marker-buffer id-loc)
+	      ;;       loc (marker-position id-loc))
+	      ;; (move-marker id-loc nil)
+	      (error "Reference '%s' not found in this buffer" ref))
+	    (cond
+	     (lob-info (setq type 'lob))
+	     (id (setq type 'id))
+	     ((and (looking-at org-babel-src-name-regexp)
+		   (save-excursion
+		     (forward-line 1)
+		     (or (looking-at org-babel-src-block-regexp)
+			 (looking-at org-babel-multi-line-header-regexp))))
+	      (setq type 'source-block))
+	     ((and (looking-at org-babel-src-name-regexp)
+		   (save-excursion
+		     (forward-line 1)
+		     (looking-at org-babel-lob-one-liner-regexp)))
+	      (setq type 'call-line))
+	     (t (while (not (setq type (org-babel-ref-at-ref-p)))
+		  (forward-line 1)
+		  (beginning-of-line)
+		  (if (or (= (point) (point-min)) (= (point) (point-max)))
+		      (error "Reference not found")))))
+	    (let ((params (append args '((:results . "silent")))))
+	      (setq result
+		    (case type
+		      (results-line (org-babel-read-result))
+		      (table        (org-babel-read-table))
+		      (list         (org-babel-read-list))
+		      (file         (org-babel-read-link))
+		      (source-block (org-babel-execute-src-block
+				     nil nil (if org-babel-update-intermediate
+						 nil params)))
+		      (call-line (save-excursion
+				   (forward-line 1)
+				   (org-babel-lob-execute
+				    (org-babel-lob-get-info))))
+		      (lob          (org-babel-execute-src-block
+				     nil lob-info params))
+		      (id           (org-babel-ref-headline-body)))))
+	    (if (symbolp result)
+		(format "%S" result)
+	      (if (and index (listp result))
+		  (org-babel-ref-index-list index result)
+		result))))))))
 
 (defun org-babel-ref-index-list (index lis)
   "Return the subset of LIS indexed by INDEX.
diff --git a/lisp/ox.el b/lisp/ox.el
index c437038..9f77af4 100644
--- a/lisp/ox.el
+++ b/lisp/ox.el
@@ -318,6 +318,7 @@ there is no export process in progress.
 It can be used to teach Babel blocks how to act differently
 according to the back-end used.")
 
+
 
 ;;; User-configurable Variables
 ;;
@@ -3434,8 +3435,7 @@ file should have."
   ;; Get a pristine copy of current buffer so Babel references can be
   ;; properly resolved.
   (let ((reference (org-export-copy-buffer)))
-    (unwind-protect (let ((org-current-export-file reference))
-		      (org-babel-exp-process-buffer))
+    (unwind-protect (org-babel-exp-process-buffer reference)
       (kill-buffer reference))))
 
 (defun org-export--copy-to-kill-ring-p ()
diff --git a/testing/lisp/test-ob-exp.el b/testing/lisp/test-ob-exp.el
index d5db187..1fe810b 100644
--- a/testing/lisp/test-ob-exp.el
+++ b/testing/lisp/test-ob-exp.el
@@ -32,8 +32,7 @@ Current buffer is a copy of the original buffer."
      (with-temp-buffer
        (org-mode)
        (insert string)
-       (let ((org-current-export-file buf))
-	 (org-babel-exp-process-buffer))
+       (org-babel-exp-process-buffer buf)
        (goto-char (point-min))
        (progn ,@body))))
 
@@ -405,6 +404,20 @@ src_emacs-lisp{(+ 1 1)}"
       (org-export-execute-babel-code)
       (buffer-string)))))
 
+(ert-deftest ob-export/reference-in-post-header ()
+  "Test references in :post header during export."
+  (should
+   (org-test-with-temp-text "
+#+NAME: foo
+#+BEGIN_SRC emacs-lisp :exports none :var bar=\"baz\"
+  (concat \"bar\" bar)
+#+END_SRC
+
+#+NAME: nofun
+#+BEGIN_SRC emacs-lisp :exports results :post foo(\"nofun\")
+#+END_SRC"
+     (org-export-execute-babel-code) t)))
+
 
 (provide 'test-ob-exp)
 
diff --git a/testing/lisp/test-ob-lob.el b/testing/lisp/test-ob-lob.el
index b0d079a..b85022b 100644
--- a/testing/lisp/test-ob-lob.el
+++ b/testing/lisp/test-ob-lob.el
@@ -83,8 +83,7 @@
       (with-temp-buffer
 	(org-mode)
 	(insert string)
-	(let ((org-current-export-file buf))
-	  (org-babel-exp-process-buffer))
+	(org-babel-exp-process-buffer buf)
 	(message (buffer-string))
 	(goto-char (point-min))
 	(should (re-search-forward "^: 0" nil t))
diff --git a/testing/lisp/test-ob.el b/testing/lisp/test-ob.el
index d7ef41a..c0ca493 100644
--- a/testing/lisp/test-ob.el
+++ b/testing/lisp/test-ob.el
@@ -645,7 +645,7 @@ on two lines
     (check-eval "no" nil)
     (check-eval "never-export" t)
     (check-eval "no-export" t)
-    (let ((org-current-export-file "something"))
+    (let ((org-babel-exp-reference-buffer (current-buffer)))
       (check-eval "never" nil)
       (check-eval "no" nil)
       (check-eval "never-export" nil)