fix: error when no tests [Closes parroty#43]

Having just this test suite:

defmodule SansConfTest do
  use ExUnit.Case
  use ExCheck

  # test "greets the world" do
  #   assert SansConf.hello() == :world
  # end
end

Would cause:

** (EXIT from #PID<0.92.0>) exited in: GenServer.stop(#PID<0.262.0>, :normal, 30000)
    ** (EXIT) exited in: :sys.terminate(#PID<0.262.0>, :normal, :infinity)
        ** (EXIT) an exception was raised:
            ** (KeyError) key :test not found in: %{}
                (excheck) lib/excheck/formatter.ex:65: ExCheck.Formatter.update_tests_counter/1

.travis.yml

@@ -4,7 +4,7 @@ elixir:
   - 1.8
   - 1.7
   - 1.6
-  - 1.5
+  # - 1.5
 
 before_script:
   - if [[ "$TRAVIS_ELIXIR_VERSION" =~ "1.9" ]]; then mix format mix.exs "{config,lib,test}/**/*.{ex,exs}" --check-formatted; fi

README.md

@@ -12,7 +12,7 @@ First add ExCheck and [triq][triq] to your project's dependencies in `mix.exs`.
 ```Elixir
   defp deps do
     [
-      {:excheck, git: "https://github.com/devstopfix/excheck.git", tag: "0.7.0", only: :test},
+      {:excheck, git: "https://github.com/devstopfix/excheck.git", tag: "0.7.1", only: :test},
       {:triq, "~> 1.2"}
     ]
   end
@@ -23,9 +23,9 @@ You need to have erlang-eunit installed in order to build triq.
 and add the following to test_helper.exs:
 
 ```Elixir
-ExCheck.start
+ExCheck.start()
 # ... other helper functions
-ExUnit.start
+ExUnit.start()
 ```
 
 ### Configuration
@@ -154,6 +154,16 @@ The following generators defined in :triq are imported through "use ExCheck" sta
 - It's a trial implementation, and has limited functionalities yet.
 - Files in test folder contains some more property examples.
 
+Issues closed:
+
+* [43](https://github.com/parroty/excheck/issues/43)
+
+### Credits
+
+- [parroty](https://github.com/parroty) for authoring this library
+- [triq developers](https://gitlab.com/triq/triq/-/project_members) for the core library
+- [luc-tielen](https://github.com/luc-tielen) for bug fixes
+
 
 [triq]: https://hex.pm/packages/triq
 [elixirv]: https://github.com/elixir-lang/elixir/blob/master/lib/elixir/pages/Compatibility%20and%20Deprecations.md

lib/excheck/formatter.ex

@@ -61,9 +61,11 @@ defmodule ExCheck.Formatter do
     total_tests
   end
 
-  defp update_tests_counter(tests_counter) when is_map(tests_counter) do
+  defp update_tests_counter(%{test: _} = tests_counter) when is_map(tests_counter) do
     total_tests = %{tests_counter | test: tests_counter.test + ExCheck.IOServer.total_tests()}
     ExCheck.IOServer.reset_test_count()
     total_tests
   end
+
+  defp update_tests_counter(%{}), do: %{}
 end

mix.exs

@@ -7,7 +7,7 @@ defmodule ExCheck.Mixfile do
       name: "ExCheck",
       source_url: "https://github.com/devstopfix/excheck",
       homepage_url: "https://github.com/parroty/ExCheck.git",
-      version: "0.7.0",
+      version: "0.7.1",
       elixir: "~> 1.5",
       deps: deps(),
       description: description(),