jmaicher · August 9, 2016 20:59 · Oct 27, 2014 · Oct 27, 2014 · Oct 27, 2014 · Oct 27, 2014
diff --git a/mutate.py → mutate.py b/mutate.py → mutate.py
diff --git a/foobar_test.py b/foobar_test.py
@@ -28,6 +28,7 @@ def run_unittest_without_output():
 
 def unittest_with_mutant(mutant):
   code = compile(mutant, '<string>', 'exec')
+  # don't do that at home
   exec code in globals()
   return run_unittest_without_output()
 

diff --git a/mutate.py → mutate.py b/mutate.py → mutate.py
diff --git a/mutate.py → mutate.py b/mutate.py → mutate.py
diff --git a/foobar.py b/foobar.py
@@ -0,0 +1,10 @@
+class FooBar:
+
+  @classmethod
+  def baz(cls, x):
+    if (x % 3 == 0) or (x % 5 == 0):
+      return "foo"
+    elif x % 2 == 0:
+      return "bar"
+    else:
+      return "baz"
diff --git a/foobar_test.py b/foobar_test.py
@@ -0,0 +1,57 @@
+import unittest
+import ast, astunparse, inspect
+from foobar import FooBar
+from mutate import mutate
+
+class FooBarTest(unittest.TestCase):
+
+  # missing case
+  def test_foo(self):
+    # self.assertEquals(FooBar.baz(9), 'foo')
+    pass
+
+  def test_bar(self):
+    self.assertEquals(FooBar.baz(2), 'bar')
+
+  def test_baz(self):
+    self.assertEquals(FooBar.baz(7), 'baz')
+
+
+def run_unittest_without_output():
+  suite = unittest.TestSuite()
+  for test in ['test_foo', 'test_bar', 'test_baz']:
+    suite.addTest(FooBarTest(test))
+  result = unittest.TestResult()
+  suite.run(result)
+  return result
+
+
+def unittest_with_mutant(mutant):
+  code = compile(mutant, '<string>', 'exec')
+  exec code in globals()
+  return run_unittest_without_output()
+
+
+def unittest_with_mutants(mutants):
+  print "Running mutation tests..."
+  passedWithMutant = False
+  for mutant in mutants:
+    result = unittest_with_mutant(mutant)
+    if result.wasSuccessful():
+      # mutant passed => failed
+      passedWithMutant = True
+      source = astunparse.unparse(mutant)
+      print "FAILED - Everything passed with the following mutant: %s" % source
+
+  if not passedWithMutant:
+    print "OK - Tested with %i mutant(s), everything covered" % len(mutants)
+
+
+if __name__ == '__main__':
+  # Test without mutations
+  unittest.main(exit=False)
+
+  # Test with mutations
+  source_ast = ast.parse(inspect.getsource(FooBar))
+  mutants = mutate(source_ast)
+  unittest_with_mutants(mutants)
diff --git a/mutate.py b/mutate.py
@@ -0,0 +1,35 @@
+import ast, _ast, copy
+
+class Mutator(ast.NodeTransformer):
+  MUTATIONS = [
+  # (FromOp, ToOp)
+    (_ast.Or, _ast.And),
+    (_ast.And, _ast.Or)
+  ]
+
+  def mutate(self, root, mutation):
+    self._changed = False
+    self._mutation = mutation
+
+    mutant = self.visit(root)
+    return (mutant, self._changed)
+
+  def visit_BoolOp(self, node):
+    (FromOp, ToOp) = self._mutation
+    if(type(node.op) == FromOp):
+      self._changed = True
+      node.op = ToOp()
+
+    return node
+
+# returns all mutants for given ast
+def mutate(ast):
+  mutants = []
+  mutator = Mutator()
+
+  for mutation in Mutator.MUTATIONS:
+    (mutant, mutated) = mutator.mutate(copy.deepcopy(ast), mutation)
+    if mutated:
+      mutants.append(mutant)
+
+  return mutants
diff --git a/stdout b/stdout
@@ -0,0 +1,19 @@
+...
+----------------------------------------------------------------------
+Ran 3 tests in 0.001s
+
+OK
+
+Running mutation tests...
+FAILED - Everything passed with the following mutant:
+
+class FooBar:
+
+    @classmethod
+    def baz(cls, x):
+        if (((x % 3) == 0) and ((x % 5) == 0)):
+            return 'foo'
+        elif ((x % 2) == 0):
+            return 'bar'
+        else:
+            return 'baz'