fix: nil couldn't delete the table. Use vim.NIL

Author: kiyoon

README.md

@@ -112,7 +112,7 @@ Most will use the current word to find the import statement, but the treesitter
     opts = {
       -- Example 1:
         -- Default behaviour for `tqdm` is `from tqdm.auto import tqdm`.
-        -- If you want to change it to `import tqdm`, you can set `import = {"tqdm"}` and `import_from = {tqdm = nil}` here.
+        -- If you want to change it to `import tqdm`, you can set `import = {"tqdm"}` and `import_from = {tqdm = vim.NIL}` here.
         -- If you want to change it to `from tqdm import tqdm`, you can set `import_from = {tqdm = "tqdm"}` here.
 
       -- Example 2:
@@ -125,20 +125,20 @@ Most will use the current word to find the import statement, but the treesitter
           -- "tqdm",
         },
 
-        ---@type table<string, string>
+        ---@type table<string, string|vim.NIL>
         import_as = {
           -- These are the default values. Here for demonstration.
           -- np = "numpy",
           -- pd = "pandas",
         },
 
-        ---@type table<string, string>
+        ---@type table<string, string|vim.NIL>
         import_from = {
-          -- tqdm = nil,
+          -- tqdm = vim.NIL,
           -- tqdm = "tqdm",
         },
 
-        ---@type table<string, string[]>
+        ---@type table<string, string[]|vim.NIL>
         statement_after_imports = {
           -- logger = { "import my_custom_logger", "", "logger = my_custom_logger.get_logger()" },
         },

lua/python_import.lua

@@ -1,8 +1,33 @@
 local config = require "python_import.config"
 local lookup_table = require "python_import.lookup_table"
 
+---In Lua, if a value in a table is set to `nil`, it is treated as if the key does not exist.
+---Thus, we use `vim.NIL` in the PythonImport.UserConfig to indicate that the value should be removed from the table.
+---@param t table
+local function remove_vim_nil(t)
+  for k, v in pairs(t) do
+    if v == vim.NIL then
+      t[k] = nil
+    end
+  end
+end
+
 local M = {}
 
+---@class PythonImport.UserExtendLookupTable
+---@field import string[]?
+---@field import_as table<string, string|vim.NIL>?
+---@field import_from table<string, string|vim.NIL>?
+---@field statement_after_imports table<string, string[]|vim.NIL>?
+
+---@class PythonImport.UserConfig
+---@field extend_lookup_table PythonImport.UserExtendLookupTable?
+---
+---Return nil to indicate no match is found and continue with the default lookup
+---Return a table to stop the lookup and use the returned table as the result
+---Return an empty table to stop the lookup. This is useful when you want to add to wherever you need to.
+---@field custom_function fun(winnr: integer, word: string, ts_node: TSNode?): string[]? | nil
+
 ---@param opts PythonImport.UserConfig
 function M.setup(opts)
   -- NOTE: This may be called twice if you lazy load the plugin
@@ -25,6 +50,10 @@ function M.setup(opts)
     config.opts.extend_lookup_table.statement_after_imports
   )
 
+  remove_vim_nil(lookup_table.import_as)
+  remove_vim_nil(lookup_table.import_from)
+  remove_vim_nil(lookup_table.statement_after_imports)
+
   -- make lookup table for faster lookup
   for _, v in ipairs(lookup_table.import) do
     lookup_table.is_import[v] = true

lua/python_import/config.lua

@@ -8,19 +8,19 @@ M.default_opts = {
       -- "pickle",
     },
 
-    ---@type table<string, string>
+    ---@type table<string, string|vim.NIL>
     import_as = {
       -- np = "numpy",
       -- pd = "pandas",
     },
 
-    ---@type table<string, string>
+    ---@type table<string, string|vim.NIL>
     import_from = {
       -- tqdm = "tqdm.auto",
       -- nn = "torch",
     },
 
-    ---@type table<string, string[]>
+    ---@type table<string, string[]|vim.NIL>
     statement_after_imports = {
       -- logger = { "import my_custom_logger", "", "logger = my_custom_logger.get_logger()" },
     },