Skip progress display when in non-terminal (pytest >= 2.9)

See pytest-dev/pytest#1397

testing/acceptance_test.py

@@ -642,3 +642,25 @@ def test_worker_id_fixture(testdir, n):
         assert worker_ids == set(['master'])
     else:
         assert worker_ids == set(['gw0', 'gw1'])
+
+
+def test_color_yes_collection_on_non_atty(testdir, request):
+    """skip collect progress report when working on non-terminals.
+
+    Similar to pytest-dev/pytest#1397
+    """
+    tr = request.config.pluginmanager.getplugin("terminalreporter")
+    if not hasattr(tr, 'isatty'):
+        pytest.skip('only valid for newer pytest versions')
+    testdir.makepyfile("""
+        import pytest
+        @pytest.mark.parametrize('i', range(10))
+        def test_this(i):
+            assert 1
+    """)
+    args = ['--color=yes', '-n2']
+    result = testdir.runpytest(*args)
+    assert 'test session starts' in result.stdout.str()
+    assert '\x1b[1m' in result.stdout.str()
+    assert 'gw0 [10] / gw1 [10]' in result.stdout.str()
+    assert 'gw0 C / gw1 C' not in result.stdout.str()