From 614af6b3c3b1aeb7e2673f18741a806cebc6676c Mon Sep 17 00:00:00 2001
From: Alexander Karle <akarle@umass.edu>
Date: Wed, 7 Nov 2018 23:58:20 -0500
Subject: [PATCH] vim: Add custom folding for help doc in Vim

This is particularly useful for writing my own doc.
---
 vim/ftplugin/help.vim | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 vim/ftplugin/help.vim

diff --git a/vim/ftplugin/help.vim b/vim/ftplugin/help.vim
new file mode 100644
index 0000000..1b11000
--- /dev/null
+++ b/vim/ftplugin/help.vim
@@ -0,0 +1,32 @@
+" Some folding settings I like to use for writing Vim plugin documentation
+" Won't work universally, but doesn't hurt to enable
+
+" Simple fold function to fold until the next ===== or ------
+function! DocTxtFoldExpr(lnum) abort
+    if getline(a:lnum + 1) =~ '^\(=\+\|-\+\)$'
+        return '<1'
+    else
+        return 1
+    endif
+endfunction
+
+" Fold Text that prints number lines folded, a preview of what header it is,
+" and the section name. Attempted to align nicely, but it breaks with tabs
+" -    6 lines: ===== INTRO .....
+" -   12 lines: ----- Example .....
+function! DocTxtFoldText() abort
+    let l = getline(v:foldstart)
+    let lp1 = getline(v:foldstart + 1)
+    let num_lines = v:foldend - v:foldstart + 1
+    let lines_text = printf("%4s", num_lines) . ' lines:'
+    let header_preview = l[0:5]
+    let section_name = lp1[0:stridx(lp1, '   ')]
+    if section_name !~ ' $'
+        let section_name = section_name . ' '
+    endif
+    return join([v:folddashes, lines_text, header_preview, section_name], ' ')
+endfunction
+
+setlocal foldexpr=DocTxtFoldExpr(v:lnum)
+setlocal foldtext=DocTxtFoldText()
+setlocal foldmethod=expr
--
libgit2 0.28.4