add git integration

lua/lib/git.lua

@@ -0,0 +1,44 @@
+local function system(v) return vim.api.nvim_call_function('system', { v }) end
+
+local function is_git_repo()
+    local is_git = system('git rev-parse')
+    return string.match(is_git, 'fatal') == nil
+end
+
+local GIT_CMD = 'git status --porcelain=v1 '
+
+local function is_folder_dirty(path)
+    local ret = system(GIT_CMD..path)
+    return ret ~= nil and ret ~= ''
+end
+
+local function create_git_checker(pattern)
+    return function(path)
+        local ret = system(GIT_CMD..path)
+        return string.match(ret, pattern) ~= nil
+    end
+end
+
+local is_modified = create_git_checker('^ ?MM?')
+local is_staged = create_git_checker('^ ?A')
+local is_unmerged = create_git_checker('^ ?UU')
+local is_untracked = create_git_checker('^%?%?')
+
+local function get_git_attr(path, is_dir)
+    if is_git_repo() == false then return '' end
+    if is_dir then
+        if is_folder_dirty(path) == true then return 'Dirty' end
+    else
+        if is_modified(path) then return 'Modified'
+        elseif is_staged(path) then return 'Staged'
+        elseif is_unmerged(path) then return 'Unmerged'
+        elseif is_untracked(path) then return 'Untracked'
+        end
+    end
+
+    return ''
+end
+
+return {
+    get_git_attr = get_git_attr;
+}