Possible bug with coderef highlighting in HTML export

Possible bug with coderef highlighting in HTML export

[Thibault Marin]

Hi all,

I am using Org mode version 9.1.3 (release_9.1.3-216-g259656 @
/.../org-mode/lisp/) and I am experiencing an issue with the exported
HTML of the following org file:

,----
| this links get highlighted [[(link0)]].
| 
| this link does not get highlighted [[(link1)]].
| 
| #+begin_src emacs-lisp -r
| 0(ref:link0)
| #+end_src
| 
| #+begin_src emacs-lisp -r
| 
| 1(ref:link1)
| #+end_src
`----

The relevant HTML output is:

,----
| <p>
| this links get highlighted <a href="#coderef-link0" class="coderef" onmouseover="CodeHighlightOn(this, 'coderef-link0');" onmouseout="CodeHighlightOff(this, 'coderef-link0');">1</a>.
| </p>
| 
| <p>
| this link does not get highlighted <a href="#coderef-link1" class="coderef" onmouseover="CodeHighlightOn(this, 'coderef-link1');" onmouseout="CodeHighlightOff(this, 'coderef-link1');">1</a>.
| </p>
| 
| <div class="org-src-container">
| <pre class="src src-emacs-lisp"><span id="coderef-link0" class="coderef-off">0</span>
| </pre>
| </div>
| 
| <div class="org-src-container">
| <pre class="src src-emacs-lisp">1
| </pre>
| </div>
`----

The issue is that the link to the line in the second source block is not
highlighted (it does not get the "coderef-off" span markup).

I tried to dig a little and it appears that `org-html-do-format-code' does not
handle empty lines at the beginning of a block.  `(org-split-string "\n1")'
returns '("1") which looses the first empty line.  The line reference received
via the `refs' variable (which has value ((2 . link1))) then becomes out of sync
with the `code' variable (split by lines) used for formatting of the code block.

I am not sure what is the best way to handle this:

1. Should the `refs' variable be built accounting for the top empty lines?
2. Alternatively, should the `org-html-do-format-code' and
   `org-export-format-code' functions count the number of top empty lines and
   adjust the line number accordingly?
3. Should top empty lines be completely deleted, before the `refs' array is
   built?

I can try to propose a patch if the best option can be decided.  Option 2 seems
relatively simple but feels like a hack.

I would appreciate any suggestions on how to best fix this.

Thanks in advance.

thibault

Re: Possible bug with coderef highlighting in HTML export

[Nicolas Goaziou]

Hello,

Thibault Marin <thibault.marin@gmx.com> writes:

> I am using Org mode version 9.1.3 (release_9.1.3-216-g259656 @
> /.../org-mode/lisp/) and I am experiencing an issue with the exported
> HTML of the following org file:
>
> ,----
> | this links get highlighted [[(link0)]].
> | 
> | this link does not get highlighted [[(link1)]].
> | 
> | #+begin_src emacs-lisp -r
> | 0(ref:link0)
> | #+end_src
> | 
> | #+begin_src emacs-lisp -r
> | 
> | 1(ref:link1)
> | #+end_src
> `----
>
> The relevant HTML output is:
>
> ,----
> | <p>
> | this links get highlighted <a href="#coderef-link0" class="coderef" onmouseover="CodeHighlightOn(this, 'coderef-link0');" onmouseout="CodeHighlightOff(this, 'coderef-link0');">1</a>.
> | </p>
> | 
> | <p>
> | this link does not get highlighted <a href="#coderef-link1" class="coderef" onmouseover="CodeHighlightOn(this, 'coderef-link1');" onmouseout="CodeHighlightOff(this, 'coderef-link1');">1</a>.
> | </p>
> | 
> | <div class="org-src-container">
> | <pre class="src src-emacs-lisp"><span id="coderef-link0" class="coderef-off">0</span>
> | </pre>
> | </div>
> | 
> | <div class="org-src-container">
> | <pre class="src src-emacs-lisp">1
> | </pre>
> | </div>
> `----
>
> The issue is that the link to the line in the second source block is not
> highlighted (it does not get the "coderef-off" span markup).

Indeed.

> I tried to dig a little and it appears that `org-html-do-format-code'
> does not handle empty lines at the beginning of a block.
> `(org-split-string "\n1")' returns '("1") which looses the first empty
> line. The line reference received via the `refs' variable (which has
> value ((2 . link1))) then becomes out of sync with the `code' variable
> (split by lines) used for formatting of the code block.
>
> I am not sure what is the best way to handle this:
>
> 1. Should the `refs' variable be built accounting for the top empty lines?
> 2. Alternatively, should the `org-html-do-format-code' and
>    `org-export-format-code' functions count the number of top empty lines and
>    adjust the line number accordingly?
> 3. Should top empty lines be completely deleted, before the `refs' array is
>    built?
>
> I can try to propose a patch if the best option can be decided.  Option 2 seems
> relatively simple but feels like a hack.
>
> I would appreciate any suggestions on how to best fix this.

Option 1 seems the best way to go. Replacing `org-split-string' with
`split-string' is straightforward in this case. However, some issues
remain in `org-html-fontify-code'.

Thank you.

Regards,

-- 
Nicolas Goaziou

Re: Possible bug with coderef highlighting in HTML export

[Thibault Marin]

[-- Attachment #1: Type: text/plain, Size: 148 bytes --]


Hi,

Hi the attach patch fixes the issue for me.  Please let me know if you
have any suggestions.

As always, thanks for the guidance.

thibault



[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0001-Fix-bug-in-HTML-export-of-code-blocks-with-starting-.patch --]
[-- Type: text/x-diff, Size: 1552 bytes --]

From a78dc91c9fd1aacb2c65f66ae5afa9ee25f56e01 Mon Sep 17 00:00:00 2001
From: thibault <thibault.marin@gmx.com>
Date: Sun, 3 Dec 2017 17:42:13 -0600
Subject: [PATCH] Fix bug in HTML export of code blocks with starting blank
 lines

* lisp/ox-html.el (org-html-do-format-code): Preverse starting blank
  lines when splitting code lines (use `split-string' instead of
  `org-split-string').

  (org-html-fontify-code): Preserve starting blank lines in returned
  code string.
---
 lisp/ox-html.el | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lisp/ox-html.el b/lisp/ox-html.el
index 0e22c1699..90a6cede0 100644
--- a/lisp/ox-html.el
+++ b/lisp/ox-html.el
@@ -2202,7 +2202,7 @@ https://github.com/hniksic/emacs-htmlize"))
 		      (org-html-htmlize-region-for-paste
 		       (point-min) (point-max))))))
 	  ;; Strip any enclosing <pre></pre> tags.
-	  (let* ((beg (and (string-match "\\`<pre[^>]*>\n*" code) (match-end 0)))
+	  (let* ((beg (and (string-match "\\`<pre[^>]*>\n?" code) (match-end 0)))
 		 (end (and beg (string-match "</pre>\\'" code))))
 	    (if (and beg end) (substring code beg end) code)))))))))
 
@@ -2215,7 +2215,7 @@ alist between line numbers and references (as returned by
 `org-export-unravel-code'), a boolean specifying if labels should
 appear in the source code, and the number associated to the first
 line of code."
-  (let* ((code-lines (org-split-string code "\n"))
+  (let* ((code-lines (split-string code "\n"))
 	 (code-length (length code-lines))
 	 (num-fmt
 	  (and num-start
-- 
2.14.1

Re: Possible bug with coderef highlighting in HTML export

[Nicolas Goaziou]

Hello,

Thibault Marin <thibault.marin@gmx.com> writes:

> Hi the attach patch fixes the issue for me.  Please let me know if you
> have any suggestions.

It looks good. Applied. Thank you.

Regards,

-- 
Nicolas Goaziou