1 files changed, 167 insertions, 0 deletions
diff --git a/lua/common_lsp/util.lua b/lua/common_lsp/util.lua
index 6da2db1c..b821854a 100644
--- a/lua/common_lsp/util.lua
+++ b/lua/common_lsp/util.lua
@@ -1,5 +1,7 @@
 local validate = vim.validate
 local api = vim.api
+local lsp = vim.lsp
+local uv = vim.loop
 
 local M = {}
 
@@ -87,6 +89,171 @@ function M.create_module_commands(module_name, commands)
   end
 end
 
+-- Some path utilities
+M.path = (function()
+  local function exists(filename)
+    local stat = uv.fs_stat(filename)
+    return stat and stat.type or false
+  end
+
+  local function is_dir(filename)
+    return exists(filename) == 'directory'
+  end
+
+  local function is_file(filename)
+    return exists(filename) == 'file'
+  end
+
+  local is_windows = uv.os_uname().sysname == "Windows"
+  local path_sep = is_windows and "\\" or "/"
+
+  local is_fs_root
+  if is_windows then
+    is_fs_root = function(path)
+      return path:match("^%a:\\\\$")
+    end
+  else
+    is_fs_root = function(path)
+      return path == "/"
+    end
+  end
+
+  local dirname
+  do
+    local strip_dir_pat = path_sep.."([^"..path_sep.."]+)$"
+    local strip_sep_pat = path_sep.."$"
+    dirname = function(path)
+      local result = path:gsub(strip_sep_pat, ""):gsub(strip_dir_pat, "")
+			if #result == 0 then
+				return "/"
+			end
+			return result
+    end
+  end
+
+  local function path_join(...)
+    return table.concat(vim.tbl_flatten {...}, path_sep)
+  end
+
+  -- Traverse the path calling cb along the way.
+  local function traverse_parents(path, cb)
+    path = uv.fs_realpath(path)
+    local dir = path
+    -- Just in case our algo is buggy, don't infinite loop.
+    for _ = 1, 100 do
+      dir = dirname(dir)
+			-- If we can't ascend further, then stop looking.
+      if cb(dir, path) then
+        return dir, path
+      end
+			if is_fs_root(dir) then
+				break
+			end
+    end
+  end
+
+  -- Iterate the path until we find the rootdir.
+  local function iterate_parents(path)
+    path = uv.fs_realpath(path)
+		local function it(s, v)
+			if is_fs_root(v) then return end
+			return dirname(v), path
+		end
+		return it, path, path
+  end
+
+  return {
+    is_dir = is_dir;
+    is_file = is_file;
+    exists = exists;
+    sep = path_sep;
+    dirname = dirname;
+    join = path_join;
+    traverse_parents = traverse_parents;
+    iterate_parents = iterate_parents;
+  }
+end)()
+
+
+-- Returns a function(root_dir), which, when called with a root_dir it hasn't
+-- seen before, will call make_config(root_dir) and start a new client.
+function M.server_per_root_dir_manager(make_config)
+  local clients = {}
+  local manager = {}
+
+  function manager.add(root_dir)
+    if not root_dir then return end
+
+    -- Check if we have a client alredy or start and store it.
+    local client_id = clients[root_dir]
+    if not client_id then
+      local new_config = make_config(root_dir)
+      new_config.root_dir = root_dir
+      new_config.on_exit = M.add_hook_before(new_config.on_exit, function()
+        clients[root_dir] = nil
+      end)
+      client_id = lsp.start_client(new_config)
+      clients[root_dir] = client_id
+    end
+    return client_id
+  end
+
+  function manager.clients()
+    local res = {}
+    for _, id in pairs(clients) do
+      local client = lsp.get_client_by_id(id)
+      if client then
+        table.insert(res, client)
+      end
+    end
+    return res
+  end
+
+  return manager
+end
+
+function M.search_ancestors(startpath, fn)
+  validate { fn = {fn, 'f'} }
+  if fn(startpath) then return startpath end
+  for path in M.path.iterate_parents(startpath) do
+    if fn(path) then return path end
+  end
+end
+
+function M.root_pattern(...)
+  local patterns = vim.tbl_flatten {...}
+  local function matcher(path)
+    for _, pattern in ipairs(patterns) do
+      if M.path.exists(M.path.join(path, pattern)) then
+        return path
+      end
+    end
+  end
+  return function(startpath)
+    return M.search_ancestors(startpath, matcher)
+  end
+end
+function M.find_git_ancestor(startpath)
+  return M.search_ancestors(startpath, function(path)
+    if M.path.is_dir(M.path.join(path, ".git")) then
+      return path
+    end
+  end)
+end
+function M.find_node_modules_ancestor(startpath)
+  return M.search_ancestors(startpath, function(path)
+    if M.path.is_dir(M.path.join(path, "node_modules")) then
+      return path
+    end
+  end)
+end
+function M.find_package_json_ancestor(startpath)
+  return M.search_ancestors(startpath, function(path)
+    if M.path.is_file(M.path.join(path, "package.json")) then
+      return path
+    end
+  end)
+end
 
 return M
 -- vim:et ts=2 sw=2