Bundle DiffEqPy.jl into diffeqpy

closes #22

MANIFEST.in

@@ -1,3 +1,4 @@
 include README.md
 include LICENSE.md
 include docs/*.txt
+include diffeqpy/*.jl

diffeqpy/__init__.py

@@ -1,6 +1,23 @@
+import os
+
 from julia import Julia
 
+script_dir = os.path.dirname(os.path.realpath(__file__))
+
+
 def setup():
     jul = Julia()
-    jul.using("DiffEqPy")
+
+    # Load ./setup.jl
+    include = jul.eval('include')  # jul.include does not work sometimes
+    include(os.path.join(script_dir, 'setup.jl'))
+
+    # Make Julia functions and types exported from
+    # DifferentialEquations accessible:
+    jul.add_module_functions('DifferentialEquations')
+
+    # pysolve has to be treated manually:
+    # See: https://github.com/JuliaPy/pyjulia/issues/117#issuecomment-323498621
+    jul.pysolve = jul.eval('pysolve')
+
     return jul

diffeqpy/setup.jl

@@ -0,0 +1,14 @@
+using DifferentialEquations
+using PyCall
+
+pysolve = PyCall.pyfunctionret(solve,Any,Vararg{PyCall.PyAny})
+inspect = pyimport("inspect")
+
+function DiffEqBase.numargs(f::PyCall.PyObject)
+    haskey(f,:py_func) ? _f = f[:py_func] : _f = f
+    if PyCall.pyversion < v"3.0.0"
+        return length(first(inspect[:getargspec](_f)))
+    else
+        return length(first(inspect[:getfullargspec](_f)))
+    end
+end