2 files changed, 201 insertions, 0 deletions
diff --git a/start/cmp/lua/cmp_nvim_lsp/init.lua b/start/cmp/lua/cmp_nvim_lsp/init.lua
new file mode 100644
index 0000000..9feb93a
--- /dev/null
+++ b/start/cmp/lua/cmp_nvim_lsp/init.lua
@@ -0,0 +1,84 @@
+local source = require('cmp_nvim_lsp.source')
+
+local M = {}
+
+---Registered client and source mapping.
+M.client_source_map = {}
+
+---Setup cmp-nvim-lsp source.
+M.setup = function()
+  vim.cmd([[
+    augroup cmp_nvim_lsp
+      autocmd!
+      autocmd InsertEnter * lua require'cmp_nvim_lsp'._on_insert_enter()
+    augroup END
+  ]])
+end
+
+local if_nil = function(val, default)
+  if val == nil then return default end
+  return val
+end
+
+M.update_capabilities = function(capabilities, override)
+  override = override or {}
+
+  local completionItem = capabilities.textDocument.completion.completionItem
+
+  completionItem.snippetSupport = if_nil(override.snippetSupport, true)
+  completionItem.preselectSupport = if_nil(override.preselectSupport, true)
+  completionItem.insertReplaceSupport = if_nil(override.insertReplaceSupport, true)
+  completionItem.labelDetailsSupport = if_nil(override.labelDetailsSupport, true)
+  completionItem.deprecatedSupport = if_nil(override.deprecatedSupport, true)
+  completionItem.commitCharactersSupport = if_nil(override.commitCharactersSupport, true)
+  completionItem.tagSupport = if_nil(override.tagSupport, { valueSet = { 1 } })
+  completionItem.resolveSupport = if_nil(override.resolveSupport, {
+    properties = {
+      'documentation',
+      'detail',
+      'additionalTextEdits',
+    }
+  })
+
+  return capabilities
+end
+
+---Refresh sources on InsertEnter.
+M._on_insert_enter = function()
+  local cmp = require('cmp')
+
+  local allowed_clients = {}
+
+  -- register all active clients.
+  for _, client in ipairs(vim.lsp.get_active_clients()) do
+    allowed_clients[client.id] = client
+    if not M.client_source_map[client.id] then
+      local s = source.new(client)
+      if s:is_available() then
+        M.client_source_map[client.id] = cmp.register_source('nvim_lsp', s)
+      end
+    end
+  end
+
+  -- register all buffer clients (early register before activation)
+  for _, client in ipairs(vim.lsp.buf_get_clients(0)) do
+    allowed_clients[client.id] = client
+    if not M.client_source_map[client.id] then
+      local s = source.new(client)
+      if s:is_available() then
+        M.client_source_map[client.id] = cmp.register_source('nvim_lsp', s)
+      end
+    end
+  end
+
+  -- unregister stopped/detached clients.
+  for client_id, source_id in pairs(M.client_source_map) do
+    if not allowed_clients[client_id] or allowed_clients[client_id]:is_stopped() then
+      cmp.unregister_source(source_id)
+      M.client_source_map[client_id] = nil
+    end
+  end
+end
+
+return M
+
diff --git a/start/cmp/lua/cmp_nvim_lsp/source.lua b/start/cmp/lua/cmp_nvim_lsp/source.lua
new file mode 100644
index 0000000..d4dd587
--- /dev/null
+++ b/start/cmp/lua/cmp_nvim_lsp/source.lua
@@ -0,0 +1,117 @@
+local source = {}
+
+source.new = function(client)
+  local self = setmetatable({}, { __index = source })
+  self.client = client
+  self.request_ids = {}
+  return self
+end
+
+source.get_debug_name = function(self)
+  return table.concat({ 'nvim_lsp', self.client.name }, ':')
+end
+
+source.is_available = function(self)
+  -- client is stopped.
+  if self.client.is_stopped() then
+    return false
+  end
+
+  -- client is not attached to current buffer.
+  if not vim.lsp.buf_get_clients(vim.api.nvim_get_current_buf())[self.client.id] then
+    return false
+  end
+
+  -- client has no completion capability.
+  if not self:_get(self.client.server_capabilities, { 'completionProvider' }) then
+    return false
+  end
+  return true;
+end
+
+source.get_trigger_characters = function(self)
+  return self:_get(self.client.server_capabilities, { 'completionProvider', 'triggerCharacters' }) or {}
+end
+
+source.complete = function(self, request, callback)
+  local params = vim.lsp.util.make_position_params(0, self.client.offset_encoding)
+  params.context = {}
+  params.context.triggerKind = request.completion_context.triggerKind
+  params.context.triggerCharacter = request.completion_context.triggerCharacter
+
+  self:_request('textDocument/completion', params, function(_, response)
+    callback(response)
+  end)
+end
+
+source.resolve = function(self, completion_item, callback)
+  -- client is stopped.
+  if self.client.is_stopped() then
+    return callback()
+  end
+
+  -- client has no completion capability.
+  if not self:_get(self.client.server_capabilities, { 'completionProvider', 'resolveProvider' }) then
+    return callback()
+  end
+
+  self:_request('completionItem/resolve', completion_item, function(_, response)
+    callback(response or completion_item)
+  end)
+end
+
+source.execute = function(self, completion_item, callback)
+  -- client is stopped.
+  if self.client.is_stopped() then
+    return callback()
+  end
+
+  -- completion_item has no command.
+  if not completion_item.command then
+    return callback()
+  end
+
+  self:_request('workspace/executeCommand', completion_item.command, function(_, _)
+    callback()
+  end)
+end
+
+source._get = function(_, root, paths)
+  local c = root
+  for _, path in ipairs(paths) do
+    c = c[path]
+    if not c then
+      return nil
+    end
+  end
+  return c
+end
+
+source._request = function(self, method, params, callback)
+  if self.request_ids[method] ~= nil then
+    self.client.cancel_request(self.request_ids[method])
+    self.request_ids[method] = nil
+  end
+  local _, request_id
+  _, request_id = self.client.request(method, params, function(arg1, arg2, arg3)
+    if self.request_ids[method] ~= request_id then
+      return
+    end
+    self.request_ids[method] = nil
+
+    -- Text changed, retry
+    if arg1 and arg1.code == -32801 then
+      self:_request(method, params, callback)
+      return
+    end
+
+    if method == arg2 then
+      callback(arg1, arg3) -- old signature
+    else
+      callback(arg1, arg2) -- new signature
+    end
+  end)
+  self.request_ids[method] = request_id
+end
+
+return source