initial copy and modifications from the original py/impl/test/dist and

looponfail code. Now works as its own "xdist" plugin.

testing/test_plugin.py

@@ -0,0 +1,61 @@
+import py
+
+import execnet
+from xdist.nodemanage import NodeManager
+
+def test_dist_incompatibility_messages(testdir):
+    Error = py.test.config.Error
+    py.test.raises(Error, "testdir.parseconfigure('--pdb', '--looponfail')")
+    result = testdir.runpytest("--pdb", "-n", "3")
+    assert result.ret != 0
+    assert "incompatible" in result.stderr.str()
+    result = testdir.runpytest("--pdb", "-d", "--tx", "popen")
+    assert result.ret != 0
+    assert "incompatible" in result.stderr.str()
+
+def test_dist_options(testdir):
+    config = testdir.parseconfigure("-n 2")
+    assert config.option.dist == "load"
+    assert config.option.tx == ['popen'] * 2
+    config = testdir.parseconfigure("-d")
+    assert config.option.dist == "load"
+
+class TestDistOptions:
+    def test_getxspecs(self, testdir):
+        config = testdir.parseconfigure("--tx=popen", "--tx", "ssh=xyz")
+        nodemanager = NodeManager(config)
+        xspecs = nodemanager._getxspecs()
+        assert len(xspecs) == 2
+        print(xspecs)
+        assert xspecs[0].popen 
+        assert xspecs[1].ssh == "xyz"
+
+    def test_xspecs_multiplied(self, testdir):
+        config = testdir.parseconfigure("--tx=3*popen",)
+        xspecs = NodeManager(config)._getxspecs()
+        assert len(xspecs) == 3
+        assert xspecs[1].popen 
+
+    def test_getrsyncdirs(self, testdir):
+        config = testdir.parseconfigure('--rsyncdir=' + str(testdir.tmpdir))
+        nm = NodeManager(config, specs=[execnet.XSpec("popen")])
+        roots = nm._getrsyncdirs()
+        assert len(roots) == 1 + 2 # pylib + xdist
+        assert testdir.tmpdir in roots
+
+    def test_getrsyncdirs_with_conftest(self, testdir):
+        p = py.path.local()
+        for bn in 'x y z'.split():
+            p.mkdir(bn)
+        testdir.makeconftest("""
+            rsyncdirs= 'x', 
+        """)
+        config = testdir.parseconfigure(
+              testdir.tmpdir, '--rsyncdir=y', '--rsyncdir=z')
+        nm = NodeManager(config, specs=[execnet.XSpec("popen")])
+        roots = nm._getrsyncdirs()
+        assert len(roots) == 3 + 2 # pylib + xdist
+        assert py.path.local('y') in roots 
+        assert py.path.local('z') in roots 
+        assert testdir.tmpdir.join('x') in roots 
+