Honour stdout on TestProgram more fully.

We were failing to pass it into the runner, and this causes hilarity
for child runners which then end up with sys.stdout in their test
  suite, rather than their stub streams.

Change-Id: I19984102547f92493f330059928f7e0b3897c38c

NEWS

@@ -10,6 +10,12 @@ NEXT
 Changes
 -------
 
+* ``stdout`` is now correctly honoured on ``run.TestProgram`` - before the
+  runner objects would be created with no stdout parameter. If construction
+  fails, the previous parameter list is attempted, permitting compatibility
+  with Runner classes that don't accept stdout as a parameter.
+  (Robert Collins)
+
 * The ``ExtendedToStreamDecorator`` now handles content objects with one less
   packet - the last packet of the source content is sent with EOF set rather
   than an empty packet with EOF set being sent after the last packet of the

testtools/distutilscmd.py

@@ -26,7 +26,7 @@ class TestCommand(Command):
 
     def __init__(self, dist):
         Command.__init__(self, dist)
-        self.runner = TestToolsTestRunner(sys.stdout)
+        self.runner = TestToolsTestRunner(stdout=sys.stdout)
 
 
     def initialize_options(self):

testtools/run.py

@@ -73,6 +73,8 @@ class TestToolsTestRunner(object):
         :param stdout: Stream to use for stdout.
         """
         self.failfast = failfast
+        if stdout is None:
+            stdout = sys.stdout
         self.stdout = stdout
 
     def list(self, test):
@@ -89,7 +91,7 @@ class TestToolsTestRunner(object):
     def run(self, test):
         "Run the given test case or test suite."
         result = TextTestResult(
-            unicode_output_stream(sys.stdout), failfast=self.failfast)
+            unicode_output_stream(self.stdout), failfast=self.failfast)
         result.startTestRun()
         try:
             return test.run(result)
@@ -185,6 +187,7 @@ class TestProgram(object):
             argv = sys.argv
         if stdout is None:
             stdout = sys.stdout
+        self.stdout = stdout
 
         self.exit = exit
         self.failfast = failfast
@@ -224,7 +227,7 @@ class TestProgram(object):
                 runner.list(self.test)
             else:
                 for test in iterate_tests(self.test):
-                    stdout.write('%s\n' % test.id())
+                    self.stdout.write('%s\n' % test.id())
 
     def usageExit(self, msg=None):
         if msg:
@@ -375,12 +378,20 @@ class TestProgram(object):
     def _get_runner(self):
         if self.testRunner is None:
             self.testRunner = TestToolsTestRunner
+        try:
+            testRunner = self.testRunner(verbosity=self.verbosity,
+                                         failfast=self.failfast,
+                                         buffer=self.buffer,
+                                         stdout=self.stdout)
+        except TypeError:
+            # didn't accept the verbosity, buffer, failfast or stdout arguments
+            # Try with the prior contract
             try:
                 testRunner = self.testRunner(verbosity=self.verbosity,
                                              failfast=self.failfast,
                                              buffer=self.buffer)
             except TypeError:
-            # didn't accept the verbosity, buffer or failfast arguments
+                # Now try calling it with defaults
                 try:
                     testRunner = self.testRunner()
                 except TypeError:

testtools/tests/test_distutilscmd.py

@@ -61,8 +61,8 @@ class TestCommandTest(TestCase):
         dist.cmdclass = {'test': TestCommand}
         dist.command_options = {
             'test': {'test_module': ('command line', 'testtools.runexample')}}
-        cmd = dist.reinitialize_command('test')
         with fixtures.MonkeyPatch('sys.stdout', stdout.stream):
+            cmd = dist.reinitialize_command('test')
             dist.run_command('test')
         self.assertThat(
             stdout.getDetails()['stdout'].as_text(),
@@ -83,8 +83,8 @@ OK
             'test': {
                 'test_suite': (
                     'command line', 'testtools.runexample.test_suite')}}
-        cmd = dist.reinitialize_command('test')
         with fixtures.MonkeyPatch('sys.stdout', stdout.stream):
+            cmd = dist.reinitialize_command('test')
             dist.run_command('test')
         self.assertThat(
             stdout.getDetails()['stdout'].as_text(),

testtools/tests/test_run.py

@@ -13,9 +13,13 @@ import testtools
 from testtools import TestCase, run
 from testtools.compat import (
     _b,
+    _u,
     StringIO,
     )
-from testtools.matchers import Contains
+from testtools.matchers import (
+    Contains,
+    MatchesRegex,
+    )
 
 
 if fixtures:
@@ -235,12 +239,27 @@ testtools.resourceexample.TestFoo.test_foo
                 self.fail('a')
             def test_b(self):
                 self.fail('b')
-        runner = run.TestToolsTestRunner(failfast=True)
         with fixtures.MonkeyPatch('sys.stdout', stdout.stream):
+            runner = run.TestToolsTestRunner(failfast=True)
             runner.run(TestSuite([Failing('test_a'), Failing('test_b')]))
         self.assertThat(
             stdout.getDetails()['stdout'].as_text(), Contains('Ran 1 test'))
 
+    def test_stdout_honoured(self):
+        self.useFixture(SampleTestFixture())
+        tests = []
+        out = StringIO()
+        exc = self.assertRaises(SystemExit, run.main,
+            argv=['prog', 'testtools.runexample.test_suite'],
+            stdout=out)
+        self.assertEqual((0,), exc.args)
+        self.assertThat(
+            out.getvalue(),
+            MatchesRegex(_u("""Tests running...
+
+Ran 2 tests in \\d.\\d\\d\\ds
+OK
+""")))
 
 
 def test_suite():