feat: walk up dir tree to find project config

lua/project_config/utils.lua

@@ -1,38 +1,51 @@
 local Path = require("plenary.path")
-local sha = require 'project_config.sha2'
+local sha = require("project_config.sha2")
 
 local utils = {}
 
 -- calculate file signature, file should be instance of Path
 function utils.file_signature(file)
-  if not file:exists() then return nil end
-  local content = string.format('%q', table.concat(file:readlines(), "\n"))
+  if not file:exists() then
+    return nil
+  end
+  local content = string.format("%q", table.concat(file:readlines(), "\n"))
   return sha.sha256(content)
 end
 
 -- generate the config file for the current cwd
 function utils.get_config_file()
   local cwd = Path:new(vim.loop.cwd())
-  local data_dir = Path:new(vim.fn.stdpath('data'))
-
+  local data_dir = Path:new(vim.fn.stdpath("data"))
   local file = sha.sha256(cwd:absolute()) .. ".vim"
-
-  return data_dir:joinpath('project_config', file)
+  local config_file = data_dir:joinpath("project_config", file)
+  if config_file:exists() then
+    return config_file
+  end
+
+  for _, path in pairs(cwd:parents()) do
+    local parent_config = data_dir:joinpath("project_config", sha.sha256(path) .. ".vim")
+    if parent_config:exists() then
+      return parent_config
+    end
+  end
+
+  return config_file
 end
 
 -- get index of value in table, or nil if missing
 function utils.index_of(table, value)
   local index = {}
-  for k, v in pairs(table) do index[v] = k end
+  for k, v in pairs(table) do
+    index[v] = k
+  end
   return index[value]
 end
 
 -- wrapper around vim confirm()
 function utils.confirm(dialog, options, default)
   local opts = table.concat(options, "\n")
   local def = utils.index_of(options, default)
-  return vim.api.nvim_eval(string.format([[confirm("%s", "%s", "%s")]], dialog,
-                                         opts, def))
+  return vim.api.nvim_eval(string.format([[confirm("%s", "%s", "%s")]], dialog, opts, def))
 end
 
 -- source config file