Factor out XDG env defaults for readability

1 files changed, 26 insertions, 15 deletions

diff --git a/vim/autoload/xdg.vim b/vim/autoload/xdg.vim
index fd7ddedf..b83d7208 100644
--- a/vim/autoload/xdg.vim
+++ b/vim/autoload/xdg.vim
@@ -1,19 +1,34 @@
+" <https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html#variables>
+let s:defaults = {
+      \ 'XDG_CACHE_HOME': '~/.cache',
+      \ 'XDG_CONFIG_HOME': '~/.config',
+      \ 'XDG_CONFIG_DIRS': '/etc/xdg',
+      \ 'XDG_DATA_HOME': '~/.local/share',
+      \ 'XDG_DATA_DIRS': '/usr/local/share/:/usr/share/',
+      \}
+
+function! s:Get(name) abort
+  let name = a:name
+  let env = environ()
+  if has_key(env, name) && strlen(env[name]) > 0
+    return env[name]
+  elseif has_key(s:defaults, name)
+    return s:defaults[name]
+  else
+    return ''
+  endif
+endfunction
+
 function! xdg#CacheDir(name) abort
   let name = a:name
-  let home = exists('$XDG_CACHE_HOME')
-        \ ? $XDG_CACHE_HOME
-        \ : '~/.cache'
+  let home = s:Get('XDG_CACHE_HOME')
   return join([home, name], '/')
 endfunction
 
 function! xdg#ConfigDirs(name) abort
   let name = a:name
-  let home = exists('$XDG_CONFIG_HOME')
-        \ ? $XDG_CONFIG_HOME
-        \ : '~/.config'
-  let dirs = exists('$XDG_CONFIG_DIRS')
-        \ ? split($XDG_CONFIG_DIRS, ':')
-        \ : ['/etc/xdg']
+  let home = s:Get('XDG_CONFIG_HOME')
+  let dirs = split(s:Get('XDG_CONFIG_DIRS'), ':')
   return map(
         \ insert(dirs, home)
         \,'join([v:val, name], "/")'
@@ -22,12 +37,8 @@ endfunction
 
 function! xdg#DataDirs(name) abort
   let name = a:name
-  let home = exists('$XDG_DATA_HOME')
-        \ ? $XDG_DATA_HOME
-        \ : '~/.local/share'
-  let dirs = exists('$XDG_DATA_DIRS')
-        \ ? split($XDG_DATA_DIRS, ':')
-        \ : ['/usr/local/share', '/usr/share']
+  let home = s:Get('XDG_DATA_HOME')
+  let dirs = split(s:Get('XDG_DATA_DIRS'), ':')
   return map(
         \ insert(dirs, home)
         \,'join([v:val, name], "/")'