Fix bug in test count reporting when using ExCheck in umbrella apps

lib/excheck/error_agent.ex

@@ -25,6 +25,11 @@ defmodule ExCheck.ErrorAgent do
     end)
   end
 
+  @doc "Clears all errors stored by this agent."
+  def clear_errors(agent) do
+    agent |> Agent.update(fn(_) -> %{} end)
+  end
+
   @doc "Stops the agent."
   def stop(agent) do
     Agent.stop(agent)

lib/excheck/formatter.ex

@@ -31,9 +31,13 @@ defmodule ExCheck.Formatter do
   end
 
   defp update_tests_counter(tests_counter) when is_integer(tests_counter) do
-    tests_counter + ExCheck.IOServer.total_tests
+    total_tests = tests_counter + ExCheck.IOServer.total_tests
+    ExCheck.IOServer.reset_test_count
+    total_tests
   end
   defp update_tests_counter(tests_counter) when is_map(tests_counter) do
-    %{tests_counter | test: tests_counter.test + ExCheck.IOServer.total_tests}
+    total_tests = %{tests_counter | test: tests_counter.test + ExCheck.IOServer.total_tests}
+    ExCheck.IOServer.reset_test_count
+    total_tests
   end
 end

lib/excheck/io_server.ex

@@ -34,6 +34,11 @@ defmodule ExCheck.IOServer do
     @server |> GenServer.call(:total_tests)
   end
 
+  @doc "Resets the test count."
+  def reset_test_count do
+    @server |> GenServer.call(:reset_test_count)
+  end
+
   @doc "Returns all error loggings from property tests"
   def errors do
     @server |> GenServer.call(:errors)
@@ -65,6 +70,10 @@ defmodule ExCheck.IOServer do
   def handle_call(:total_tests, _from, state = %State{tests: tests}) do
     {:reply, tests, state}
   end
+  def handle_call(:reset_test_count, _from, state = %State{agent: agent}) do
+    agent |> ErrAgent.clear_errors
+    {:reply, :ok, %State{state | tests: 0}}
+  end
   def handle_call(:errors, _from, state = %State{agent: agent}) do
     response = ErrAgent.errors(agent)
     {:reply, response, state}