Fix get_surrounding_module/2 ast helper

Author: NJichev

lib/next_ls/commands/alias.ex

@@ -25,7 +25,7 @@ defmodule NextLS.Commands.Alias do
   def run(opts) do
     with {:ok, %{text: text, uri: uri, position: position}} <- unify(opts(), Map.new(opts)),
          {:ok, ast} = parse(text),
-         {:ok, defm} <- ASTHelpers.get_nearest_module(ast, position),
+         {:ok, defm} <- ASTHelpers.get_surrounding_module(ast, position),
          {:ok, {:__aliases__, _, modules}} <- get_node(ast, position) do
       range = make_range(defm)
       indent = EditHelpers.get_indent(text, range.start.line)

lib/next_ls/extensions/elixir_extension/code_action/require.ex

@@ -16,7 +16,7 @@ defmodule NextLS.ElixirExtension.CodeAction.Require do
 
     with {:ok, require_module} <- get_edit(diagnostic.message),
          {:ok, ast} <- parse_ast(text),
-         {:ok, defm} <- ASTHelpers.get_nearest_module(ast, range.start),
+         {:ok, defm} <- ASTHelpers.get_surrounding_module(ast, range.start),
          indentation <- get_indent(text, defm),
          nearest <- find_nearest_node_for_require(defm),
          range <- get_edit_range(nearest) do

lib/next_ls/helpers/ast_helpers.ex

@@ -154,12 +154,15 @@ defmodule NextLS.ASTHelpers do
     end)
   end
 
-  @spec get_nearest_module(ast :: Macro.t(), position :: Position.t()) :: {:ok, Macro.t()} | {:error, String.t()}
-  def get_nearest_module(ast, position) do
+  @spec get_surrounding_module(ast :: Macro.t(), position :: Position.t()) :: {:ok, Macro.t()} | {:error, String.t()}
+  def get_surrounding_module(ast, position) do
     defm =
       ast
       |> Macro.prewalker()
       |> Enum.filter(fn node -> match?({:defmodule, _, _}, node) end)
+      |> Enum.filter(fn {_, ctx, _} ->
+        position.line + 1 - ctx[:line] >= 0
+      end)
       |> Enum.min_by(
         fn {_, ctx, _} ->
           abs(ctx[:line] - 1 - position.line)

test/next_ls/helpers/ast_helpers_test.exs

@@ -76,7 +76,7 @@ defmodule NextLS.ASTHelpersTest do
     end
   end
 
-  describe "find_nearest_module/2" do
+  describe "get_surrounding_module/2" do
     test "finds the nearest defmodule definition in the ast" do
       {:ok, ast} =
         Spitfire.parse("""
@@ -95,18 +95,18 @@ defmodule NextLS.ASTHelpersTest do
 
       for line <- lines do
         position = %Position{line: line, character: 0}
-        assert {:ok, {:defmodule, _, [{:__aliases__, _, [:Foo]} | _]}} = ASTHelpers.get_nearest_module(ast, position)
+        assert {:ok, {:defmodule, _, [{:__aliases__, _, [:Foo]} | _]}} = ASTHelpers.get_surrounding_module(ast, position)
       end
 
       lines = 5..7
 
       for line <- lines do
         position = %Position{line: line, character: 0}
-        assert {:ok, {:defmodule, _, [{:__aliases__, _, [:Bar]} | _]}} = ASTHelpers.get_nearest_module(ast, position)
+        assert {:ok, {:defmodule, _, [{:__aliases__, _, [:Bar]} | _]}} = ASTHelpers.get_surrounding_module(ast, position)
       end
 
       position = %Position{line: 0, character: 0}
-      assert {:ok, {:defmodule, _, [{:__aliases__, _, [:Test]} | _]}} = ASTHelpers.get_nearest_module(ast, position)
+      assert {:ok, {:defmodule, _, [{:__aliases__, _, [:Test]} | _]}} = ASTHelpers.get_surrounding_module(ast, position)
     end
 
     test "errors out when it can't find a module" do
@@ -116,7 +116,25 @@ defmodule NextLS.ASTHelpersTest do
         """)
 
       position = %Position{line: 0, character: 0}
-      assert {:error, "no defmodule definition"} = ASTHelpers.get_nearest_module(ast, position)
+      assert {:error, "no defmodule definition"} = ASTHelpers.get_surrounding_module(ast, position)
+    end
+
+    test "it finds the nearest surrounding module" do
+      {:ok, ast} =
+        Spitfire.parse("""
+        defmodule Test do
+          alias Foo
+          alias Bar
+          alias Baz
+
+          defmodule Quix do
+            defstruct [:key]
+          end
+        end
+        """)
+
+      position = %Position{line: 4, character: 0}
+      assert {:ok, {:defmodule, _, [{:__aliases__, _, [:Test]} | _]}} = ASTHelpers.get_surrounding_module(ast, position)
     end
   end
 end