fix crash on capture arg completion

Author: lukaszsamson

apps/elixir_ls_utils/lib/completion_engine.ex

@@ -184,6 +184,10 @@ defmodule ElixirLS.Utils.CompletionEngine do
         # expand_struct_fields_or_local_or_var(code, List.to_string(local_or_var), shell)
         expand_local_or_var(List.to_string(local_or_var), env, metadata, cursor_position)
 
+      # elixir >= 1.18
+      {:capture_arg, capture_arg} ->
+        expand_local_or_var(List.to_string(capture_arg), env, metadata, cursor_position)
+
       {:local_arity, local} ->
         expand_local(List.to_string(local), true, env, metadata, cursor_position)
 

apps/elixir_ls_utils/test/complete_test.exs

@@ -470,6 +470,20 @@ defmodule ElixirLS.Utils.CompletionEngineTest do
     assert [] == expand(~c"~r")
   end
 
+  test "function completion using a capture arg" do
+    env = %Env{
+      vars: [
+        %VarInfo{
+          name: :"&12",
+          version: 1
+        }
+      ]
+    }
+
+    assert [%{name: "&12", type: :variable}] =
+             expand(~c"&1", env)
+  end
+
   test "function completion using a variable bound to a module" do
     env = %Env{
       vars: [