Allow capturing deprecated log level, closes #12605

Author: josevalim

lib/ex_unit/lib/ex_unit/capture_log.ex

@@ -96,7 +96,14 @@ defmodule ExUnit.CaptureLog do
   @doc since: "1.13.0"
   @spec with_log(keyword, (-> result)) :: {result, String.t()} when result: any
   def with_log(opts \\ [], fun) when is_list(opts) do
-    opts = Keyword.put_new(opts, :level, nil)
+    opts =
+      if opts[:level] == :warn do
+        IO.warn("level: :warn is deprecated, please use :warning instead")
+        Keyword.put(opts, :level, :warning)
+      else
+        opts
+      end
+
     {:ok, string_io} = StringIO.open("")
 
     try do

lib/ex_unit/test/ex_unit/capture_log_test.exs

@@ -78,6 +78,19 @@ defmodule ExUnit.CaptureLogTest do
     end
   end
 
+  test "deprecated log level" do
+    ExUnit.CaptureIO.capture_io(:stderr, fn ->
+      output =
+        capture_log([level: :warn], fn ->
+          Logger.log(:warn, "ABC")
+          Logger.log(:warning, "DEF")
+        end)
+
+      assert output =~ "ABC"
+      assert output =~ "DEF"
+    end)
+  end
+
   describe "with_log/2" do
     test "returns the result and the log" do
       {result, log} =