Update util.jl

Author: DilumAluthge

test/util.jl

@@ -1,7 +1,27 @@
-function recursively_unwrap_task_failed_ex(ex::ErrorException)
-  return ex
+extract_test_result_value(test_result::Test.Pass) = test_result.value
+
+recursively_unwrap_ex(ex::ErrorException) = ex
+recursively_unwrap_ex(ex::Base.IOError) = ex
+function recursively_unwrap_ex(outer_ex::TaskFailedException)
+  new_thing = outer_ex.task.exception
+  return recursively_unwrap_ex(new_thing)
+end
+
+Base.@kwdef struct ConfigForTestingTaskFailedException
+  expected_outer_ex_T
+  expected_inner_ex_T
+  expected_inner_ex_INSTANCE
 end
 
-function recursively_unwrap_task_failed_ex(outer_ex::TaskFailedException)
-  return recursively_unwrap_task_failed_ex(outer_ex.task.exception)
+function test_task_failed_exception(test_result::Test.Pass, cfg::ConfigForTestingTaskFailedException)
+  observed_outer_ex = extract_test_result_value(test_result)
+  @test observed_outer_ex isa expected_outer_ex_T
+  observed_inner_ex = recursively_unwrap_task_failed_ex(observed_outer_ex)
+  @test observed_inner_ex isa typeof(expected_inner_ex_INSTANCE)
+  @test observed_inner_ex == expected_inner_ex_INSTANCE
+  return nothing
 end
+
+
+
+@test observed_inner_ex isa expected_inner_ex_T # TODO