Document incompatibility with parallelization in pytest-xdist. Close #8.

Author: RKrahl

doc/src/install.rst

@@ -12,6 +12,16 @@ System requirements
 (Python 3.1 is not supported by pytest 2.8.0 itself.)
 
 
+Interaction with other packages
+-------------------------------
+
+   pytest-xdist
+      pytest-xdist features test run parallelization,
+      e.g. distributing tests over separate processes that run in
+      parallel.  This is based on the assumption that the tests can be
+      run independent of each other.  pytest-dependency will only work
+      if you disable parallelization in pytest-xdist.
+
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