Allow any default parameter in two-fer (#432)

* Allow any default parameter in two-fer

Fixes #431

* Update tests for two-fer

* mix format

---------

Co-authored-by: Jeremie Gillet <[email protected]>

lib/elixir_analyzer/test_suite/two_fer.ex

@@ -45,19 +45,19 @@ defmodule ElixirAnalyzer.TestSuite.TwoFer do
 
     # function header
     form do
-      def two_fer(_ignore \\ "you")
+      def two_fer(_ignore \\ _ignore)
     end
 
     # function without a guard and with a do block
     form do
-      def two_fer(_ignore \\ "you") do
+      def two_fer(_ignore \\ _ignore) do
         _ignore
       end
     end
 
     # function with do block
     form do
-      def two_fer(_ignore \\ "you") when _ignore do
+      def two_fer(_ignore \\ _ignore) when _ignore do
         _ignore
       end
     end

test/elixir_analyzer/test_suite/two_fer_test.exs

@@ -91,9 +91,6 @@ defmodule ElixirAnalyzer.TestSuite.TwoFerTest do
         defmodule TwoFer do
           def two_fer(_)
         end,
-        defmodule TwoFer do
-          def two_fer(name \\ "wrong default value")
-        end,
         defmodule TwoFer do
           def two_fer(name) do
             "One for #{name}, one for me."
@@ -114,6 +111,21 @@ defmodule ElixirAnalyzer.TestSuite.TwoFerTest do
     end
   end
 
+  test_exercise_analysis "accepts any value as the default parameter",
+    comments_exclude: [Constants.two_fer_use_default_parameter()] do
+    [
+      defmodule TwoFer do
+        def two_fer(name \\ "you")
+      end,
+      defmodule TwoFer do
+        def two_fer(name \\ "wrong default value")
+      end,
+      defmodule TwoFer do
+        def two_fer(name \\ nil)
+      end
+    ]
+  end
+
   describe "function header" do
     test_exercise_analysis "refer when using a function header",
       comments_include: [Constants.two_fer_use_of_function_header()] do