feat(client): control concurrent discovery

See #13

doc/neotest.txt

@@ -59,7 +59,7 @@ Default values:
       enabled = true
     },
     discovery = {
-      concurrent = true,
+      concurrent = 0,
       enabled = true
     },
     floating = {
@@ -187,7 +187,7 @@ Class~
 {neotest.Config.discovery}
 Fields~
 {enabled} `(boolean)`
-{concurrent} `(boolean)` Parse files concurrently. Disable if experiencing performance issues.
+{concurrent} `(integer)` Number of workers to parse files concurrently. 0 automatically assigns number based on CPU. Set to 1 if experiencing lag.
 
 Class~
 {neotest.Config.running}

lua/neotest/client/init.lua

@@ -244,47 +244,34 @@ function NeotestClient:_update_positions(path, args)
         end
       end
       local files = lib.func_util.filter_list(adapter.is_test_file, lib.files.find(path))
-      return lib.files.parse_dir_from_files(path, files)
+      local positions = lib.files.parse_dir_from_files(path, files)
+      self._state:update_positions(adapter_id, positions)
+      self:_parse_files(adapter_id, path, files)
     else
-      return adapter.discover_positions(path)
+      local positions = adapter.discover_positions(path)
+      if positions then
+        self._state:update_positions(adapter_id, positions)
+      end
     end
   end)
   if not success or not positions then
     logger.error("Couldn't find positions in path", path, positions)
     return
   end
-  self._state:update_positions(adapter_id, positions)
-
-  if positions:data().type == "dir" then
-    self:_parse_dir_files(path, adapter_id)
-  end
 end
 
-function NeotestClient:_parse_dir_files(path, adapter_id)
-  local tree = assert(self._state:positions(adapter_id, path))
-  local parse_funcs = {}
-  for _, node in tree:iter_nodes() do
-    local pos = node:data()
-    if pos.type == "file" and #node:children() == 0 then
-      table.insert(parse_funcs, function()
-        self:_update_positions(pos.id, { adapter = adapter_id })
-      end)
+function NeotestClient:_parse_files(adapter_id, root, paths)
+  local function worker()
+    while #paths > 0 do
+      self:_update_positions(table.remove(paths), { adapter = adapter_id })
     end
   end
 
-  if #parse_funcs == 0 then
-    return
-  end
-
-  local root = tree:data().path
-
-  if config.projects[root].discovery.concurrent then
-    async.util.join(parse_funcs)
-  else
-    for _, func in ipairs(parse_funcs) do
-      func()
-    end
+  local workers = {}
+  for _ = 1, config.projects[root].discovery.concurrent do
+    table.insert(workers, worker)
   end
+  async.util.join(workers)
 end
 
 ---@private

lua/neotest/config/init.lua

@@ -19,7 +19,7 @@ local function define_highlights()
   hi default NeotestMarked ctermfg=Brown guifg=#F79000 gui=bold
   hi default NeotestTarget ctermfg=Red guifg=#F70067
   hi default link NeotestUnknown Normal
-]])
+]] )
 end
 
 local augroup = vim.api.nvim_create_augroup("NeotestColorSchemeRefresh", {})
@@ -45,7 +45,7 @@ define_highlights()
 
 ---@class neotest.Config.discovery
 ---@field enabled boolean
----@field concurrent boolean Parse files concurrently. Disable if experiencing performance issues.
+---@field concurrent integer Number of workers to parse files concurrently. 0 automatically assigns number based on CPU. Set to 1 if experiencing lag.
 
 ---@class neotest.Config.running
 ---@field concurrent boolean Run tests concurrently when an adapter provides multiple commands to run
@@ -101,7 +101,7 @@ local default_config = {
   adapters = {},
   discovery = {
     enabled = true,
-    concurrent = true,
+    concurrent = 0,
   },
   running = {
     concurrent = true,
@@ -202,18 +202,35 @@ local user_config = default_config
 ---@type neotest.Config
 local NeotestConfigModule = {}
 
+local convert_concurrent = function(val)
+  if val == 0 or val == true then
+    return #vim.loop.cpu_info() + 4
+  end
+  if val == false then
+    return 1
+  end
+  assert(type(val) == "number", "concurrent must be a boolean or a number")
+  return val
+end
+
 ---@param config neotest.Config
 ---@private
 function NeotestConfigModule.setup(config)
   user_config = vim.tbl_deep_extend("force", default_config, config)
+  --- Avoid mutating default for docgen
+  user_config.discovery = vim.tbl_deep_extend(
+    "force",
+    user_config.discovery,
+    { concurrent = convert_concurrent(user_config.discovery.concurrent) }
+  )
 
   user_config.projects = setmetatable({}, {
-    __index = function(_, key)
+    __index = function()
       return user_config
     end,
   })
   for project_root, project_config in pairs(config.projects or {}) do
-    NeotestConfigModule.setup_project(project_root, config)
+    NeotestConfigModule.setup_project(project_root, project_config)
   end
 end
 
@@ -225,6 +242,8 @@ function NeotestConfigModule.setup_project(project_root, config)
     discovery = user_config.discovery,
     running = user_config.running,
   })
+  user_config.projects[path].discovery.concurrent =
+  convert_concurrent(user_config.projects[path].discovery.concurrent)
 end
 
 function NeotestConfigModule._format_default()