Provide test/4 with teardown clause

README.md

@@ -28,10 +28,10 @@ bddr:test([given_app_started(),
 
 ## ...it doesn't do XYZ?
 
-No, the implementation is four lines of code. No parse transforms, no
-macros. It's the developer's responsibility to provide his/her abstractions for
-the tested components. Remember, your tests are just Erlang code. Make it
-readable and extensible for others. Be humane.
+No, the implementation is minimal. No parse transforms, no macros. It's the
+developer's responsibility to provide his/her abstractions for the tested
+components. Remember, your tests are just Erlang code. Make it readable and
+extensible for others. Be humane.
 
 ----------
 

src/bddr.erl

@@ -1,7 +1,28 @@
 -module(bddr).
--export([test/3]).
+-export([test/3, test/4]).
 
-test(Given, When, Then) when is_function(Given, 0) ->
-    Then(When(Given()));
 test(Given, When, Then) ->
-    Then(When(Given)).
+    test(Given, When, Then, fun null_teardown/1).
+
+test(Given, When, Then, Teardown) ->
+    Environment = run_given(Given),
+    Result = run_test(Environment, When, Then),
+    _ = (catch Teardown(Environment)),
+    return(Result).
+
+%% Internal
+
+null_teardown(_) -> ok.
+
+run_given(G) when is_function(G, 0) -> G();
+run_given(G) -> G.
+
+run_test(E, W, T) ->
+    try T(W(E))
+    catch E:R -> {bddr_failure, {E, R}}
+    end.
+
+return({bddr_failure, {exit, E}}) -> exit(E);
+return({bddr_failure, {throw, T}}) -> throw(T);
+return({bddr_failure, {error, E}}) -> error(E);
+return(Result) -> Result.

test/bddr_SUITE.erl

@@ -16,7 +16,9 @@ all() -> [givens_can_be_a_lambda,
 
           then_clause_can_access_action_result,
           then_clause_matches_on_action_result,
-          then_with_unexpected_result_raises_function_clause
+          then_with_unexpected_result_raises_function_clause,
+
+          test_provides_teardown_option
          ].
 
 givens_can_be_a_lambda(_) ->
@@ -80,10 +82,20 @@ then_with_unexpected_result_raises_function_clause(_) ->
                         fun(_) -> nay end,
                         fun(yay) -> this_will_fail end)).
 
+test_provides_teardown_option(_) ->
+    bddr:test(spawn(fun echo/0),
+              fun(_) -> some_user_action end,
+              fun(_) -> ok end,
 
-%% Non-test functions
+              fun(Pid) -> Pid ! self(),
+                          receive ok -> ok end,
+                          false = is_process_alive(Pid) end).
 
 
+%% Non-test functions
+echo() ->
+    receive From -> From ! ok end.
+
 compiles(Source) ->
     try {ModName, Bin} = dynamic_compile:from_string(Source),
          is_atom(ModName) andalso is_binary(Bin)