fix issue 271 - dont write junitxml on slave nodes

CHANGELOG

@@ -1,6 +1,8 @@
 Changes between 2.3.4 and 2.3.5dev
 -----------------------------------
 
+- issue 271 - dont write junitxml on slave nodes
+
 - Issue 274 - dont try to show full doctest example
   when doctest does not know the example location
 

_pytest/junitxml.py

@@ -70,7 +70,8 @@ def pytest_addoption(parser):
 
 def pytest_configure(config):
     xmlpath = config.option.xmlpath
-    if xmlpath:
+    # prevent opening xmllog on slave nodes (xdist)
+    if xmlpath and not hasattr(config, 'slaveinput'):
         config._xml = LogXML(xmlpath, config.option.junitprefix)
         config.pluginmanager.register(config._xml)
 

testing/test_junitxml.py

@@ -289,6 +289,25 @@ def test_mangle_testnames():
     assert newnames == ["a.pything", "Class", "method"]
 
 
+def test_dont_configure_on_slaves(tmpdir):
+    gotten = []
+    class FakeConfig:
+        def __init__(self):
+            self.pluginmanager = self
+            self.option = self
+        junitprefix = None
+        #XXX: shouldnt need tmpdir ?
+        xmlpath = str(tmpdir.join('junix.xml'))
+        register = gotten.append
+    fake_config = FakeConfig()
+    from _pytest import junitxml
+    junitxml.pytest_configure(fake_config)
+    assert len(gotten) == 1
+    FakeConfig.slaveinput = None
+    junitxml.pytest_configure(fake_config)
+    assert len(gotten) == 1
+
+
 class TestNonPython:
     def test_summing_simple(self, testdir):
         testdir.makeconftest("""