Vimdoc writer (#11132)

Support for vimdoc, documentation format used by vim in its help pages.
Relies heavily on definition lists and precise text alignment to generate tags.

Author: reptee

MANUAL.txt

@@ -361,6 +361,7 @@ header when requesting a document from a URL:
     - `s5` ([S5] HTML and JavaScript slide show)
     - `tei` ([TEI Simple])
     - `typst` ([typst])
+    - `vimdoc` ([Vimdoc])
     - `xml` (XML version of native AST)
     - `xwiki` ([XWiki markup])
     - `zimwiki` ([ZimWiki markup])
@@ -511,6 +512,7 @@ header when requesting a document from a URL:
 [DokuWiki markup]: https://www.dokuwiki.org/dokuwiki
 [ZimWiki markup]: https://zim-wiki.org/manual/Help/Wiki_Syntax.html
 [XWiki markup]: https://www.xwiki.org/xwiki/bin/view/Documentation/UserGuide/Features/XWikiSyntax/
+[Vimdoc]: https://vimhelp.org/helphelp.txt.html#help-writing
 [TWiki markup]: https://twiki.org/cgi-bin/view/TWiki/TextFormattingRules
 [TikiWiki markup]: https://doc.tiki.org/Wiki-Syntax-Text#The_Markup_Language_Wiki-Syntax
 [Haddock markup]: https://www.haskell.org/haddock/doc/html/ch03s08.html

data/templates/default.vimdoc

@@ -0,0 +1,16 @@
+$if(filename)$*${filename}*	$endif$$if(abstract)$${abstract}$endif$$if(filename)$
+
+
+$endif$$if(combined-title)$${combined-title}
+
+
+$endif$$toc-reminder$
+
+$if(toc)$
+$toc$
+
+$endif$
+
+$body$
+
+ $modeline$

pandoc.cabal

@@ -23,7 +23,7 @@ description:     Pandoc is a Haskell library for converting from one markup
                    txt2tags, djot)
                  - HTML formats (HTML 4 and 5)
                  - Ebook formats (EPUB v2 and v3, FB2)
-                 - Documentation formats (GNU TexInfo, Haddock)
+                 - Documentation formats (GNU TexInfo, Haddock, Vimdoc)
                  - Roff formats (man, ms)
                  - TeX formats (LaTeX, ConTeXt)
                  - Typst
@@ -110,6 +110,7 @@ data-files:
                  data/templates/fonts.latex
                  data/templates/font-settings.latex
                  data/templates/after-header-includes.latex
+                 data/templates/default.vimdoc
 
                  -- translations
                  data/translations/*.yaml
@@ -386,6 +387,7 @@ extra-source-files:
                  test/writer.zimwiki
                  test/writer.xwiki
                  test/writer.muse
+                 test/writer.vimdoc
                  test/ansi-test.ansi
                  test/writers-lang-and-dir.latex
                  test/writers-lang-and-dir.context
@@ -433,6 +435,8 @@ extra-source-files:
                  test/odt/markdown/*.md
                  test/odt/native/*.native
                  test/pod-reader.pod
+                 test/vimdoc/*.markdown
+                 test/vimdoc/*.vimdoc
 source-repository head
   type:          git
   location:      https://github.com/jgm/pandoc.git
@@ -660,6 +664,7 @@ library
                    Text.Pandoc.Writers.AnnotatedTable,
                    Text.Pandoc.Writers.BibTeX,
                    Text.Pandoc.Writers.ANSI,
+                   Text.Pandoc.Writers.Vimdoc,
                    Text.Pandoc.PDF,
                    Text.Pandoc.UTF8,
                    Text.Pandoc.Scripting,

src/Text/Pandoc/Writers.hs

@@ -79,6 +79,7 @@ module Text.Pandoc.Writers
     , writeXML
     , writeXWiki
     , writeZimWiki
+    , writeVimdoc
     , getWriter
     ) where
 
@@ -132,6 +133,7 @@ import Text.Pandoc.Writers.Typst
 import Text.Pandoc.Writers.XML
 import Text.Pandoc.Writers.XWiki
 import Text.Pandoc.Writers.ZimWiki
+import Text.Pandoc.Writers.Vimdoc
 
 data Writer m = TextWriter (WriterOptions -> Pandoc -> m Text)
               | ByteStringWriter (WriterOptions -> Pandoc -> m BL.ByteString)
@@ -206,6 +208,7 @@ writers = [
   ,("djot"         , TextWriter writeDjot)
   ,("ansi"         , TextWriter writeANSI)
   ,("xml"          , TextWriter writeXML)
+  ,("vimdoc"       , TextWriter writeVimdoc)
   ]
 
 -- | Retrieve writer, extensions based on formatSpec (format+extensions).