Workaround for Blackfriday issue 239 for example blocks too

- https://github.com/russross/blackfriday/issues/239
- https://github.com/kaushalmodi/ox-hugo/issues/57

ox-blackfriday.el

@@ -393,6 +393,27 @@ Replaces \"_\" with \"%5F\".
 Workaround for Blackfriday bug https://github.com/russross/blackfriday/issues/278."
   (replace-regexp-in-string "_" "%5F" url))
 
+;;;; Blackfriday Issue 239 Workaround
+(defun org-blackfriday-issue-239-workaround (text parent-type)
+  "Prefix Markdown list characters with zero width space.
+
+Hack to avert the Blackfriday bug:
+https://github.com/russross/blackfriday/issues/239.  Remove this
+hack once that issue is resolved.
+
+Details: https://github.com/kaushalmodi/ox-hugo/issues/57
+
+Prefix the ASTERISK (0x2a), PLUS SIGN (0x2b) and HYPHEN-MINUS
+(0x2d) characters with ZERO WIDTH SPACE (0x200b), if they
+appear at BOL."
+  ;; (message "[ox-bf bfissue 239 DBG] parent type: %S" parent-type)
+  (if (equal 'item parent-type)
+      (setq text (replace-regexp-in-string "^\\s-*[-+*] " "​\\&" text))
+    ;; There's a ZERO WIDTH SPACE char (0x200b) here     ^^,
+    ;;                            (after «"», but before «\\&"» above)
+    ;; It's not visible (because zero width), but it's there.
+    text))
+
 
 
 ;;; Transcode Functions
@@ -413,13 +434,12 @@ information."
   (let* ((parent-element (org-export-get-parent example-block))
          (parent-type (car parent-element))
          (backticks (make-string org-blackfriday--code-block-num-backticks ?`))
+         (example (org-export-format-code-default example-block info))
          ret)
     ;; (message "[ox-bf example-block DBG]")
     ;; (message "[ox-bf example-block DBG] parent type: %S" parent-type)
-    (setq ret (format "%stext\n%s%s"
-                      backticks
-                      (org-export-format-code-default example-block info)
-                      backticks))
+    (setq ret (org-blackfriday-issue-239-workaround example parent-type))
+    (setq ret (format "%stext\n%s%s" backticks ret backticks))
     (setq ret (org-blackfriday--div-wrap-maybe example-block ret))
     (when (equal 'quote-block parent-type)
       ;; If the current example block is inside a quote block, future
@@ -787,18 +807,7 @@ INFO is a plist used as a communication channel."
     ;; (message "[ox-bf src-block DBG]")
     ;; (message "ox-bf [dbg] code: %s" code)
     ;; (message "[ox-bf src-block DBG] parent type: %S" parent-type)
-    ;; Hack to avert a bug in Blackfriday
-    ;; Details: https://github.com/kaushalmodi/ox-hugo/issues/57
-    ;; Prefix the ASTERISK (0x2a), PLUS SIGN (0x2b) and HYPHEN-MINUS
-    ;; (0x2d) characters with ZERO WIDTH SPACE (0x200b), if they
-    ;; appear at BOL.
-    ;; FIXME: Remove this hack in the when form when
-    ;; https://github.com/russross/blackfriday/issues/239 is resolved.
-    (when (equal 'item parent-type)
-      (setq code (replace-regexp-in-string "^[-+*] " "​\\&" code)))
-    ;; There's a ZERO WIDTH SPACE char (0x200b) here ^^,
-    ;;                            (after «"», but before «\\&"» above)
-    ;; It's not visible (because zero width), but it's there.
+    (setq code (org-blackfriday-issue-239-workaround code parent-type))
     (prog1
         (format "%s%s\n%s%s" backticks lang code backticks)
       (when (equal 'quote-block parent-type)

test/site/content-org/all-posts.org

@@ -1243,7 +1243,9 @@ prefix = /dir/where/you/want/to/install/org # Default: /usr/share
 #+begin_src emacs-lisp
 (message "hello")
 #+end_src
-** Source block with list syntax in a list            :@upstream:blackfriday:
+** Source and example blocks with list syntax in a list
+*** Source blocks                                    :src_block:lists:hyphen:
+**** Source block with list syntax in a list          :@upstream:blackfriday:
 :PROPERTIES:
 :EXPORT_DATE: 2017-08-01
 :EXPORT_FILE_NAME: list-has-src-block-with-list-syntax
@@ -1266,7 +1268,7 @@ Below is an example of such a case:
   #+end_src
 - List item 3
 
-Another such example:
+Another such example, but with space before a hyphen in source block:
 
 1. First item
    #+begin_src yaml
@@ -1276,10 +1278,10 @@ Another such example:
 2. Second item
    #+begin_src yaml
    ports:
-   - port: 80
+    - port: 80
    #+end_src
 3. Third item
-** Source block without list syntax in a list
+**** Source block without list syntax in a list
 :PROPERTIES:
 :EXPORT_DATE: 2017-08-01
 :EXPORT_FILE_NAME: list-has-src-block-but-no-list-syntax
@@ -1288,12 +1290,12 @@ This case is not affected by /Blackfriday/ [[https://github.com/russross/blackfr
 code block does not have Markdown syntax lists.
 - List item 1
   #+begin_src md
-,*abc*
-/def/
-=def=
+  ,*abc*
+ /def/
+ =def=
   #+end_src
 - List item 2
-** Source block with list syntax but not in a list
+**** Source block with list syntax but not in a list
 :PROPERTIES:
 :EXPORT_DATE: 2017-08-01
 :EXPORT_FILE_NAME: src-block-outside-list-with-list-syntax
@@ -1301,6 +1303,43 @@ code block does not have Markdown syntax lists.
 #+begin_src md
 - list 1
 #+end_src
+*** Example blocks                               :lists:hyphen:example_block:
+**** Example block with list syntax in a list          :@upstream:blackfriday:
+:PROPERTIES:
+:EXPORT_FILE_NAME: list-has-example-block-with-list-syntax
+:END:
+An upstream bug in {{{bfissue(239)}}} caused fenced code blocks in
+lists to not render correctly if they contain Markdown syntax
+lists. =ox-hugo= provides a hack to get around that bug.
+
+Below is an example of such a case:
+
+- List item 1
+  #+begin_example
+  - List item 1.1 in code block
+  - List item 1.2 in code block
+  #+end_example
+- List item 2
+  #+begin_example
+  + List item 2.1 in code block
+  + List item 2.2 in code block
+  #+end_example
+- List item 3
+
+Another such example, but with spaces before the hyphens in example
+blocks:
+
+- List item 1
+  #+begin_example
+   - List item 1.1 in code block
+   - List item 1.2 in code block
+  #+end_example
+- List item 2
+  #+begin_example
+    + List item 2.1 in code block
+    + List item 2.2 in code block
+  #+end_example
+- List item 3
 ** Org Babel Results
 :PROPERTIES:
 :EXPORT_FILE_NAME: org-babel-results-preserve-indent

test/site/content/posts/list-has-example-block-with-list-syntax.md

@@ -0,0 +1,43 @@
++++
+title = "Example block with list syntax in a list"
+tags = ["src-block", "lists", "hyphen", "example-block", "blackfriday"]
+categories = ["upstream"]
+draft = false
++++
+
+An upstream bug in _Blackfriday_ Issue #[239](https://github.com/russross/blackfriday/issues/239) caused fenced code blocks in
+lists to not render correctly if they contain Markdown syntax
+lists. `ox-hugo` provides a hack to get around that bug.
+
+Below is an example of such a case:
+
+-   List item 1
+
+    ```text
+    ​- List item 1.1 in code block
+    ​- List item 1.2 in code block
+    ```
+-   List item 2
+
+    ```text
+    ​+ List item 2.1 in code block
+    ​+ List item 2.2 in code block
+    ```
+-   List item 3
+
+Another such example, but with spaces before the hyphens in example
+blocks:
+
+-   List item 1
+
+    ```text
+    ​- List item 1.1 in code block
+    ​- List item 1.2 in code block
+    ```
+-   List item 2
+
+    ```text
+    ​+ List item 2.1 in code block
+    ​+ List item 2.2 in code block
+    ```
+-   List item 3

test/site/content/posts/list-has-src-block-but-no-list-syntax.md

@@ -1,7 +1,7 @@
 +++
 title = "Source block without list syntax in a list"
 date = 2017-08-01
-tags = ["src-block"]
+tags = ["src-block", "lists", "hyphen"]
 draft = false
 +++
 

test/site/content/posts/list-has-src-block-with-list-syntax.md

@@ -1,7 +1,7 @@
 +++
 title = "Source block with list syntax in a list"
 date = 2017-08-01
-tags = ["src-block", "blackfriday"]
+tags = ["src-block", "lists", "hyphen", "blackfriday"]
 categories = ["upstream"]
 draft = false
 +++
@@ -26,7 +26,7 @@ Below is an example of such a case:
     ```
 -   List item 3
 
-Another such example:
+Another such example, but with space before a hyphen in source block:
 
 1.  First item
 
@@ -38,6 +38,6 @@ Another such example:
 
     ```yaml
     ports:
-    ​- port: 80
+    ​ - port: 80
     ```
 3.  Third item

test/site/content/posts/src-block-outside-list-with-list-syntax.md

@@ -1,7 +1,7 @@
 +++
 title = "Source block with list syntax but not in a list"
 date = 2017-08-01
-tags = ["src-block"]
+tags = ["src-block", "lists", "hyphen"]
 draft = false
 +++