handling memory error in timeout utility

codewars_test/test_framework.py

@@ -85,6 +85,7 @@ def assert_approx_equals(
     expect(abs((actual - expected) / div) < margin, message, allow_raise)
 
 
+
 '''
 Usage:
 @describe('describe text')
@@ -94,7 +95,6 @@ def it1():
         # some test cases...
 '''
 
-
 def _timed_block_factory(opening_text):
     from timeit import default_timer as timer
     from traceback import format_exception
@@ -126,28 +126,37 @@ def wrapper(func):
 it = _timed_block_factory('IT')
 
 
-'''
-Timeout utility
-Usage:
-@timeout(sec)
-def some_tests():
-    any code block...
-Note: Timeout value can be a float.
-'''
 
-
-def timeout(sec):
+def timeout(sec, user_msg=""):
+    
     def wrapper(func):
-        from multiprocessing import Process
-        msg = 'Should not throw any exceptions inside timeout'
+        from multiprocessing import Process, Value
 
-        def wrapped():
-            expect_no_error(msg, func)
-        process = Process(target=wrapped)
+        def wrapped(finished):
+            try:
+                func()
+                finished.value = 1.0
+            except BaseException as e:
+                finished.value = 1.0
+                fail("Should not throw any exceptions inside timeout: {}".format(repr(e)))
+
+        finished = Value('d',0.0)
+        # needed to know if the process crashed without any "feedback" and before any
+        # assertion has been done in the wrapped function or the wrapper (happens if 
+        # the heap memory explodes)
+
+        process = Process(target=wrapped, args=(finished,))
         process.start()
         process.join(sec)
+
         if process.is_alive():
-            fail('Exceeded time limit of {:.3f} seconds'.format(sec))
+            msg = 'Exceeded time limit of {:.3f} seconds'.format(sec)
+            if user_msg:
+                msg += ': ' + user_msg
+            fail(msg)
             process.terminate()
             process.join()
+        elif not finished.value:
+            fail('Something went wrong: the process running the function crashed without feedback (probably saturating the available memory)')
+
     return wrapper

tests/fixtures/timeout_failing_inner_test_assertion.expected.txt

@@ -0,0 +1,6 @@
+
+<DESCRIBE::>group 1
+
+<FAILED::>Didn't pass
+
+<COMPLETEDIN::>30.41

tests/fixtures/timeout_failing_inner_test_assertion.py

@@ -0,0 +1,8 @@
+import codewars_test as test
+
+
+@test.describe("group 1")
+def group_1():
+    @test.timeout(0.01)
+    def test_1():
+        test.fail("Didn't pass")

tests/fixtures/timeout_failing_memory_crash.expected.txt

@@ -0,0 +1,8 @@
+
+<DESCRIBE::>group 1
+
+<IT::>check memory crash
+
+<FAILED::>Something went wrong: the process running the function crashed without feedback (probably saturating the available memory)
+
+<COMPLETEDIN::>30.41

tests/fixtures/timeout_failing.py → tests/fixtures/timeout_failing_time.py

@@ -5,7 +5,6 @@
 def group_1():
     @test.timeout(0.01)
     def test_1():
-        x = 0
-        while x < 10 ** 9:
-            x += 1
+        while True:
+            pass
         test.pass_()

tests/fixtures/timeout_failing_user_raise_error.expected.txt

@@ -0,0 +1,8 @@
+
+<DESCRIBE::>group 1
+
+<IT::>it 1
+
+<FAILED::>Should not throw any exceptions inside timeout: KeyError()
+
+<COMPLETEDIN::>30.41

tests/fixtures/timeout_failing_user_raise_error.py

@@ -0,0 +1,11 @@
+import codewars_test as test
+
+
+@test.describe("group 1")
+def group_1():
+    @test.it("it 1")
+    def group_1():
+        @test.timeout(0.2)
+        def test_1():
+            raise KeyError()
+            test.pass_()

tests/fixtures/timeout_failing_with_user_message.expected.txt

@@ -0,0 +1,6 @@
+
+<DESCRIBE::>group 1
+
+<FAILED::>Exceeded time limit of 0.010 seconds: nope...
+
+<COMPLETEDIN::>30.41

tests/fixtures/timeout_failing_with_user_message.py

@@ -0,0 +1,10 @@
+import codewars_test as test
+
+
+@test.describe("group 1")
+def group_1():
+    @test.timeout(0.01, "nope...")
+    def test_1():
+        while True:
+            pass
+        test.pass_()

tests/fixtures/timeout_passing.expected.txt

@@ -3,6 +3,4 @@
 
 <PASSED::>Test Passed
 
-<PASSED::>Test Passed
-
 <COMPLETEDIN::>17.19