[PATCH v2 1/2] Add project-wide .vimrc configuration

[Felipe Contreras <felipe.contreras@gmail.com>]

It's not efficient that everyone must set specific configurations in all
their ~/.vimrc files; we can have a project-wide .vimrc that everyone
can use.

There's different ways to load this configuration, for example with
vim-addon-local-vimrc [1], but we don't need much of the complexity of
these solutions.

Instead I created a simple loader that is in the contrib area, which can
be installed with:

  cp -aT contrib/vim ~/.vim/pack/plugins/start/git

Then, add the location of the Git repository to your ~/.vimrc:

  let g:gitvimrc_whitelist = [ expand('$HOME') . '/dev/git' ]

Then the project-wide configuration will be loaded, which sets the
correct filetype for the documentation, and also the default indentation
of c, sh, perl, and asciidoc files.

These default configurations can be overridden in the typical way (by
adding the corresponding file in ~/.vim/after/ftplugin).

We could add the vim modelines at the bottom of every file, like other
projects do, but this seems more sensible.

[1] https://github.com/MarcWeber/vim-addon-local-vimrc

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
---
 .vimrc                          | 22 ++++++++++++++++++++++
 contrib/vim/plugin/gitvimrc.vim | 21 +++++++++++++++++++++
 2 files changed, 43 insertions(+)
 create mode 100644 .vimrc
 create mode 100644 contrib/vim/plugin/gitvimrc.vim

diff --git a/.vimrc b/.vimrc
new file mode 100644
index 0000000000..602c746477
--- /dev/null
+++ b/.vimrc
@@ -0,0 +1,22 @@
+" To make use of these configurations install the git plugin provided in
+" the contrib section:
+"
+"   cp -aT contrib/vim ~/.vim/pack/plugins/start/git
+"
+" Then whitelist the location of this directory to your ~/.vimrc:
+"
+"   let g:gitvimrc_whitelist = [ expand('$HOME') . '/dev/git' ]
+"
+" You can add multiple locations, or specify a regexp pattern.
+"
+
+augroup git
+	au BufRead,BufNewFile */Documentation/*.txt set filetype=asciidoc
+
+	au FileType c setl noexpandtab tabstop=8 shiftwidth=0 cino=(s,:0,l1,t0
+	au FileType sh setl noexpandtab tabstop=8 shiftwidth=0
+	au FileType perl setl noexpandtab tabstop=8 shiftwidth=0
+	au FileType asciidoc setl noexpandtab tabstop=8 shiftwidth=0 autoindent
+augroup END
+
+" vim: noexpandtab tabstop=8 shiftwidth=0
diff --git a/contrib/vim/plugin/gitvimrc.vim b/contrib/vim/plugin/gitvimrc.vim
new file mode 100644
index 0000000000..c3946e5410
--- /dev/null
+++ b/contrib/vim/plugin/gitvimrc.vim
@@ -0,0 +1,21 @@
+let s:gitvimrc_whitelist = get(g:, 'gitvimrc_whitelist', [])
+
+function LoadGitVimrc()
+  let l:top = trim(system('git rev-parse --show-toplevel'))
+  if l:top == '' | return | endif
+  let l:file = l:top . '/.vimrc'
+  if !filereadable(l:file) | return | endif
+
+  let l:found = 0
+  for l:pattern in s:gitvimrc_whitelist
+    if (match(l:top, l:pattern) != -1)
+      let l:found = 1
+      break
+    endif
+  endfor
+  if !l:found | return | endif
+
+  exec 'source ' . fnameescape(l:file)
+endf
+
+call LoadGitVimrc()
-- 
2.29.2