fix: options not being correctly read when loaded before cmp

by delaying the initialization of `source`.

fixes #29

lua/cmp_tmux/source.lua

@@ -5,7 +5,6 @@
 -- license: MIT
 --
 
-local config = require('cmp.config')
 local Tmux = require('cmp_tmux.tmux')
 
 local source = {}
@@ -20,39 +19,52 @@ local default_config = {
 }
 
 local function create_config()
+    local config = require('cmp.config')
     local source_config = config.get_source_config('tmux') or {}
     return vim.tbl_extend('force', default_config, source_config.option or {})
 end
 
 source.new = function()
     local self = setmetatable({}, { __index = source })
-    self.config = create_config()
-    self.tmux = Tmux.new(self.config)
     return self
 end
 
 source.get_debug_name = function()
     return 'tmux'
 end
 
+function source:config()
+    if self.config_impl == nil then
+        self.config_impl = create_config()
+    end
+    return self.config_impl
+end
+
+function source:tmux()
+    if self.tmux_impl == nil then
+        self.tmux_impl = Tmux.new(self:config())
+    end
+    return self.tmux_impl
+end
+
 function source:is_available()
-    return self.tmux:is_enabled()
+    return self:tmux():is_enabled()
 end
 
 function source:get_keyword_pattern()
-    return self.config.keyword_pattern
+    return self:config().keyword_pattern
 end
 
 function source:get_trigger_characters()
     local ft = vim.bo.filetype
-    local tcft = self.config.trigger_characters_ft[ft]
-    return tcft or self.config.trigger_characters
+    local tcft = self:config().trigger_characters_ft[ft]
+    return tcft or self:config().trigger_characters
 end
 
 function source:complete(request, callback)
     local word = string.sub(request.context.cursor_before_line, request.offset)
 
-    self.tmux:complete(word, function(words)
+    self:tmux():complete(word, function(words)
         if words == nil then
             return callback()
         end
@@ -62,7 +74,7 @@ function source:complete(request, callback)
                 word = w,
                 label = w,
                 labelDetails = {
-                    detail = self.config.label,
+                    detail = self:config().label,
                 },
             }
         end, words)