gitmodules: Set foldmethod=expr per modeline

Fold away every submodule entry.

Add section headers.

.config/vim/ftplugin/gitconfig.vim

@@ -0,0 +1,3 @@
+" Create folds for all lines between a section start and either the next section
+" start or blank line
+setlocal foldexpr=getline(v:lnum)=~'^\\['?'>1':getline(v:lnum+1)=~'(^\\[\\|^$)'?'<1':getline(v:lnum)=~'^\\t'

.gitmodules

@@ -1,11 +1,17 @@
+# vim: foldmethod=expr
+# See the foldexpr in ftplugin/gitconfig.vim as well as vim-sort-folds
+
+# meta
 [submodule "dotbot"]
 	path = meta/dotbot
 	url = https://github.com/anishathalye/dotbot
 
+# bin
 [submodule "fzf"]
 	path = .local/bin/fzf-repo
 	url = https://github.com/junegunn/fzf
 
+# git
 [submodule "diff-so-fancy"]
 	path = .config/git/diff-so-fancy
 	url = https://github.com/so-fancy/diff-so-fancy
@@ -13,6 +19,7 @@
 	path = .config/git/git-filter-repo
 	url = https://github.com/newren/git-filter-repo
 
+# tmux
 [submodule "tmux-continuum"]
 	path = .config/tmux/plugins/tmux-continuum
 	url = https://github.com/tmux-plugins/tmux-continuum
@@ -29,6 +36,7 @@
 	path = .config/tmux/plugins/tpm
 	url = https://github.com/tmux-plugins/tpm
 
+# vim
 [submodule "arm-syntax-vim"]
 	path = .config/vim/pack/plugins/opt/arm-syntax-vim
 	url = https://github.com/ARM9/arm-syntax-vim
@@ -87,6 +95,7 @@
 	path = .config/vim/pack/plugins/opt/vim-textobj-user
 	url = https://github.com/kana/vim-textobj-user
 
+# zsh
 [submodule "fzf-tab"]
 	path = .config/zsh/plugins/fzf-tab
 	url = https://github.com/Aloxaf/fzf-tab