Do not re-use the same chatId forever

lua/eca/mediator.lua

@@ -86,4 +86,8 @@ function mediator:mcps()
   return mcps
 end
 
+function mediator:id()
+  return self.state and self.state.id
+end
+
 return mediator

lua/eca/sidebar.lua

@@ -1275,7 +1275,7 @@ function M:_send_message(message)
 
   local contexts = self:get_contexts()
   self.mediator:send("chat/prompt", {
-    chatId = self.id,
+    chatId = self.mediator:id(),
     requestId = tostring(os.time()),
     message = message,
     contexts = contexts or {},

lua/eca/state.lua

@@ -17,6 +17,7 @@
 ---@field status string
 ---
 ---@class eca.State
+---@field id string?
 ---@field status eca.StateStatus
 ---@field config eca.StateConfig
 ---@field usage eca.StateUsage
@@ -26,6 +27,7 @@ local State = {}
 ---@return eca.State
 function State._new()
   local instance = setmetatable({
+    id = nil,
     status = {
       state = "idle",
       text = "Idle",
@@ -99,6 +101,10 @@ function State:_chat_content_received(message)
     return
   end
 
+  if message.params.chatId and message.params.chatId ~= self.id then
+    self.id = message.params.chatId
+  end
+
   local content = message.params.content
 
   if content.type == "progress" then

tests/test_chat_id.lua

@@ -0,0 +1,118 @@
+local MiniTest = require("mini.test")
+local eq = MiniTest.expect.equality
+local child = MiniTest.new_child_neovim()
+
+local function flush(ms)
+  vim.uv.sleep(ms or 50)
+  child.api.nvim_eval("1")
+end
+
+local function setup_env()
+  -- Initialize everything
+  _G.Server = require('eca.server').new()
+  _G.State = require('eca.state').new()
+  _G.Mediator = require('eca.mediator').new(_G.Server, _G.State)
+  _G.Sidebar = require('eca.sidebar').new(1, _G.Mediator)
+end
+
+local T = MiniTest.new_set({
+  hooks = {
+    pre_case = function()
+      child.restart({ "-u", "scripts/minimal_init.lua" })
+      child.lua([[require('eca.commands').setup()]])
+      child.lua_func(setup_env)
+    end,
+    post_case = function()
+      child.lua("if _G.Server and _G.Server.process then _G.Server.process:kill() end")
+    end,
+    post_once = child.stop,
+  },
+})
+
+T["chat id lifecycle"] = MiniTest.new_set()
+
+T["chat id lifecycle"]["mediator id follows state id updates"] = function()
+  -- Initially there is no chat id
+  eq(child.lua_get("_G.State.id"), vim.NIL)
+  eq(child.lua_get("_G.Mediator:id()"), vim.NIL)
+
+  -- Simulate a content notification with a chatId
+  child.lua([[require('eca.observer').notify({
+    method = 'chat/contentReceived',
+    params = { chatId = 'chat-123', content = { type = 'progress', state = 'responding', text = '...' } },
+  })]])
+  flush()
+
+  eq(child.lua_get("_G.State.id"), "chat-123")
+  eq(child.lua_get("_G.Mediator:id()"), "chat-123")
+end
+
+T["chat id lifecycle"]["send request uses current chat id when available"] = function()
+  -- Ensure no chat id initially
+  eq(child.lua_get("_G.State.id"), vim.NIL)
+
+  -- Send a message before any chat id exists
+  child.lua([[_G.Sidebar:_send_message('hello')]])
+
+  -- Inspect the last message sent to the server
+  local last_json = child.lua_get("_G.Server.messages[#_G.Server.messages].content")
+  local parsed = child.lua_get("vim.json.decode(...)", { last_json })
+  eq(parsed.method, "chat/prompt")
+  -- When id is nil, chatId should be absent in params
+  eq(parsed.params.chatId == nil, true)
+
+  -- Now simulate receiving a new chat id
+  child.lua([[require('eca.observer').notify({
+    method = 'chat/contentReceived',
+    params = { chatId = 'chat-new', content = { type = 'progress', state = 'responding', text = '...' } },
+  })]])
+  flush()
+  eq(child.lua_get("_G.State.id"), "chat-new")
+
+  -- Send another message; it should include the new chat id
+  child.lua([[_G.Sidebar:_send_message('again')]])
+  local last_json2 = child.lua_get("_G.Server.messages[#_G.Server.messages].content")
+  local parsed2 = child.lua_get("vim.json.decode(...)", { last_json2 })
+  eq(parsed2.method, "chat/prompt")
+  eq(parsed2.params.chatId, "chat-new")
+end
+
+T["chat id lifecycle"]["reopening neovim uses a new chat id"] = function()
+  -- First session: set a chat id via notification
+  child.lua([[require('eca.observer').notify({
+    method = 'chat/contentReceived',
+    params = { chatId = 'chat-first', content = { type = 'progress', state = 'responding', text = '...' } },
+  })]])
+  flush()
+  eq(child.lua_get("_G.State.id"), "chat-first")
+
+  -- Restart Neovim to simulate reopening
+  child.restart({ "-u", "scripts/minimal_init.lua" })
+  child.lua([[require('eca.commands').setup()]])
+  child.lua_func(setup_env)
+
+  -- New session should not carry over the previous chat id
+  eq(child.lua_get("_G.State.id"), vim.NIL)
+
+  -- First message should not include a chatId
+  child.lua([[_G.Sidebar:_send_message('hello after reopen')]])
+  local last_json3 = child.lua_get("_G.Server.messages[#_G.Server.messages].content")
+  local parsed = child.lua_get("vim.json.decode(...)", { last_json3 })
+  eq(parsed.method, "chat/prompt")
+  eq(parsed.params.chatId == nil, true)
+
+  -- After receiving content, a new chat id should be used
+  child.lua([[require('eca.observer').notify({
+    method = 'chat/contentReceived',
+    params = { chatId = 'chat-second', content = { type = 'progress', state = 'responding', text = '...' } },
+  })]])
+  flush()
+  eq(child.lua_get("_G.State.id"), "chat-second")
+
+  child.lua([[_G.Sidebar:_send_message('use new id')]])
+  local last_json4 = child.lua_get("_G.Server.messages[#_G.Server.messages].content")
+  local parsed2 = child.lua_get("vim.json.decode(...)", { last_json4 })
+  eq(parsed2.params.chatId, "chat-second")
+end
+
+return T