feat: add language settings for copilot answers

* added answer language setting

* Update rplugin/python3/CopilotChat/handlers/chat_handler.py

Co-authored-by: Dung Duc Huynh (Kaka) <870029+jellydn@users.noreply.github.com>

* added document to README and setup function

---------

Co-authored-by: neutrinoA4 <test@test.com>
Co-authored-by: Dung Duc Huynh (Kaka) <870029+jellydn@users.noreply.github.com>

README.md

@@ -36,6 +36,7 @@ return {
       show_help = "yes", -- Show help text for CopilotChatInPlace, default: yes
       debug = false, -- Enable or disable debug mode, the log file will be in ~/.local/state/nvim/CopilotChat.nvim.log
       disable_extra_info = 'no', -- Disable extra information (e.g: system prompt) in the response.
+      language = "English" -- Copilot answer language settings when using default prompts. Default language is English.
       -- proxy = "socks5://127.0.0.1:3000", -- Proxies requests via https or socks.
     },
     build = function()

lua/CopilotChat/init.lua

@@ -15,13 +15,15 @@ _COPILOT_CHAT_GLOBAL_CONFIG = {}
 --       - disable_extra_info: ('yes' | 'no') default: 'yes'.
 --       - hide_system_prompt: ('yes' | 'no') default: 'yes'.
 --       - proxy: (string?) default: ''.
+--       - language: (string?) default: ''.
 --       - prompts: (table?) default: default_prompts.
 --       - debug: (boolean?) default: false.
 M.setup = function(options)
   vim.g.copilot_chat_show_help = options and options.show_help or 'yes'
   vim.g.copilot_chat_disable_separators = options and options.disable_extra_info or 'yes'
   vim.g.copilot_chat_hide_system_prompt = options and options.hide_system_prompt or 'yes'
   vim.g.copilot_chat_proxy = options and options.proxy or ''
+  vim.g.copilot_chat_language = options and options.language or ''
   local debug = options and options.debug or false
   _COPILOT_CHAT_GLOBAL_CONFIG.debug = debug
 

rplugin/python3/CopilotChat/handlers/chat_handler.py

@@ -26,6 +26,7 @@ def __init__(self, nvim: MyNvim, buffer: MyBuffer):
         self.copilot: Copilot = None
         self.buffer: MyBuffer = buffer
         self.proxy: str = os.getenv("HTTPS_PROXY") or os.getenv("ALL_PROXY") or ""
+        self.language = self.nvim.eval("g:copilot_chat_language")
 
     # public
 
@@ -79,6 +80,8 @@ def _construct_system_prompt(self, prompt: str):
             system_prompt = system_prompts.COPILOT_TESTS
         elif prompt == system_prompts.EXPLAIN_SHORTCUT:
             system_prompt = system_prompts.COPILOT_EXPLAIN
+        if self.language != "":
+            system_prompt = system_prompt + "\n" + system_prompts.PROMPT_ANSWER_LANGUAGE_TEMPLATE.substitute(language=self.language)
         return system_prompt
 
     def _add_start_separator(

rplugin/python3/CopilotChat/handlers/inplace_chat_handler.py

@@ -20,6 +20,7 @@ def __init__(self, nvim: MyNvim):
         self.diff_mode: bool = False
         self.model: str = MODEL_GPT4
         self.system_prompt: str = "SENIOR_DEVELOPER_PROMPT"
+        self.language = self.nvim.eval("g:copilot_chat_language")
 
         # Add user prompts collection
         self.user_prompts = self.nvim.eval("g:copilot_chat_user_prompts")

rplugin/python3/CopilotChat/handlers/vsplit_chat_handler.py

@@ -14,6 +14,7 @@ def __init__(self, nvim: MyNvim):
                 "filetype": "copilot-chat",
             },
         )
+        self.language = self.nvim.eval("g:copilot_chat_language")
 
     def vsplit(self):
         self.buffer.option("filetype", "copilot-chat")

rplugin/python3/CopilotChat/prompts.py

@@ -1,3 +1,5 @@
+from string import Template
+
 # pylint: disable=locally-disabled, multiple-statements, fixme, line-too-long
 COPILOT_INSTRUCTIONS = """You are an AI programming assistant.
 When asked for you name, you must respond with "GitHub Copilot".
@@ -249,3 +251,4 @@
 """
 PROMPT_SIMPLE_DOCSTRING = "add simple docstring to this code"
 PROMPT_SEPARATE = "add comments separating the code into sections"
+PROMPT_ANSWER_LANGUAGE_TEMPLATE = Template("Please answer in ${language}")