gnus-art.el, mm-uu.el: Misc improvements for displaying MIME parts

* gnus-art.el (gnus-mime-inline-part, gnus-mm-display-part):
Work for the last MIME part in an article.
(gnus-mime-display-single): Suppress excessive newlines between parts.

* mm-uu.el (mm-uu-dissect): Assume that separators may be accompanied
by leading or trailing newline.

3 files changed, 57 insertions, 26 deletions

diff --git a/lisp/gnus/ChangeLog b/lisp/gnus/ChangeLog
index dad0444fcb2..275aa91eaeb 100644
--- a/lisp/gnus/ChangeLog
+++ b/lisp/gnus/ChangeLog
@@ -1,3 +1,12 @@
+2014-05-14  Katsumi Yamaoka  <yamaoka@jpl.org>
+
+        * gnus-art.el (gnus-mime-inline-part, gnus-mm-display-part):
+        Work for the last MIME part in an article.
+        (gnus-mime-display-single): Suppress excessive newlines between parts.
+
+        * mm-uu.el (mm-uu-dissect): Assume that separators may be accompanied
+        by leading or trailing newline.
+
 2014-05-09  Katsumi Yamaoka  <yamaoka@jpl.org>
 
         * gnus-art.el (gnus-mm-display-part): Don't put article out of sight
diff --git a/lisp/gnus/gnus-art.el b/lisp/gnus/gnus-art.el
index a05507ead37..ccf7984c595 100644
--- a/lisp/gnus/gnus-art.el
+++ b/lisp/gnus/gnus-art.el
@@ -5316,7 +5316,8 @@ Compressed files like .gz and .bz2 are decompressed."
       (when (= b (prog1
                      btn
                    (setq btn (previous-single-property-change
-                              (next-single-property-change btn 'gnus-data)
+                              (or (next-single-property-change btn 'gnus-data)
+                                  (point-max))
                               'gnus-data))))
         (setq b btn))
       (if (and (not arg) (mm-handle-undisplayer handle))
@@ -5353,12 +5354,14 @@ Compressed files like .gz and .bz2 are decompressed."
       (if (featurep 'emacs)
           (delete-region
            (point)
-           (text-property-any (point) (point-max) 'gnus-data nil))
+           (or (text-property-any (point) (point-max) 'gnus-data nil)
+               (point-max)))
         (let* ((end (text-property-any (point) (point-max) 'gnus-data nil))
                (annots (annotations-at end)))
           (delete-region (point)
-                         ;; FIXME: why isn't this simply `end'?
-                         (if annots (1+ end) end))
+                         (if end
+                             (if annots (1+ end) end)
+                           (point-max)))
           (dolist (annot annots)
             (set-extent-endpoints annot (point) (point)))))
       (unless (search-backward "\n\n" nil t)
@@ -5691,7 +5694,8 @@ all parts."
               (select-window win)
               (goto-char point)))
           (setq point (previous-single-property-change
-                       (next-single-property-change point 'gnus-data)
+                       (or (next-single-property-change point 'gnus-data)
+                           (point-max))
                        'gnus-data))
           (if (mm-handle-displayed-p handle)
               ;; This will remove the part.
@@ -5728,12 +5732,15 @@ all parts."
       (gnus-insert-mime-button handle id (list (mm-handle-displayed-p handle)))
       (if (featurep 'emacs)
           (delete-region
-           (point) (text-property-any (point) (point-max) 'gnus-data nil))
+           (point)
+           (or (text-property-any (point) (point-max) 'gnus-data nil)
+               (point-max)))
         (let* ((end (text-property-any (point) (point-max) 'gnus-data nil))
                (annots (annotations-at end)))
           (delete-region (point)
-                         ;; FIXME: why isn't this simply `end'?
-                         (if annots (1+ end) end))
+                         (if end
+                             (if annots (1+ end) end)
+                           (point-max)))
           (dolist (annot annots)
             (set-extent-endpoints annot (point) (point)))))
       (unless (search-backward "\n\n" nil t)
@@ -6036,9 +6043,6 @@ If nil, don't show those extra buttons."
                     (eq id gnus-mime-buttonized-part-id))
             (gnus-insert-mime-button
              handle id (list (or display (and not-attachment text)))))
-          (gnus-article-insert-newline)
-          (when (or display (and text not-attachment))
-            (forward-line -1))
           (setq beg (point))
           (cond
            (display
@@ -6048,12 +6052,18 @@ If nil, don't show those extra buttons."
                                        (set-buffer gnus-summary-buffer)
                                      (error))
                                    gnus-newsgroup-ignored-charsets)))
-              (gnus-bind-safe-url-regexp (mm-display-part handle t)))
-            (goto-char (point-max)))
+              (gnus-bind-safe-url-regexp (mm-display-part handle t))))
            ((and text not-attachment)
-            (gnus-article-insert-newline)
-            (mm-display-inline handle)
-            (goto-char (point-max))))
+            (mm-display-inline handle)))
+          (goto-char (point-max))
+          (if (string-match "\\`image/" type)
+              (gnus-article-insert-newline)
+            (if (prog1
+                    (= (skip-chars-backward "\n") -1)
+                  (forward-char 1))
+                (gnus-article-insert-newline)
+              (put-text-property (point) (point-max) 'gnus-undeletable t))
+            (goto-char (point-max)))
           ;; Do highlighting.
           (save-excursion
             (save-restriction
diff --git a/lisp/gnus/mm-uu.el b/lisp/gnus/mm-uu.el
index 423324a86f4..d91d2a41c8f 100644
--- a/lisp/gnus/mm-uu.el
+++ b/lisp/gnus/mm-uu.el
@@ -673,22 +673,34 @@ value of `mm-uu-text-plain-type'."
                      (goto-char text-start)
                      (re-search-forward "." start-point t)))
               (push
-               (mm-make-handle (mm-uu-copy-to-buffer text-start start-point)
-                               mm-uu-text-plain-type)
+               (mm-make-handle
+                (mm-uu-copy-to-buffer
+                 text-start
+                 ;; A start-separator is likely accompanied by
+                 ;; a leading newline.
+                 (if (and (eq (char-before start-point) ?\n)
+                          (eq (char-before (1- start-point)) ?\n))
+                     (1- start-point)
+                   start-point))
+                mm-uu-text-plain-type)
                result))
           (push
            (funcall (mm-uu-function-extract entry))
            result)
           (goto-char (setq text-start end-point))))
       (when result
-        (if (and (> (point-max) (1+ text-start))
-                 (save-excursion
-                   (goto-char text-start)
-                   (re-search-forward "." nil t)))
-            (push
-             (mm-make-handle (mm-uu-copy-to-buffer text-start (point-max))
-                             mm-uu-text-plain-type)
-             result))
+        (goto-char text-start)
+        (when (re-search-forward "." nil t)
+          (push (mm-make-handle
+                 (mm-uu-copy-to-buffer
+                  ;; An end-separator is likely accompanied by
+                  ;; a trailing newline.
+                  (if (eq (char-after text-start) ?\n)
+                      (1+ text-start)
+                    text-start)
+                  (point-max))
+                 mm-uu-text-plain-type)
+                result))
         (setq result (cons "multipart/mixed" (nreverse result))))
       result)))