implement decorator to mark bug related tests as expected failures

myhdl/test/conversion/conftest.py

@@ -0,0 +1,20 @@
+from itertools import chain
+
+import pytest
+
+from myhdl.conversion import verify
+
+xfail = pytest.mark.xfail
+
+hdlmap = {
+    'verilog': ('icarus', 'vlog'),
+    'vhdl': ('GHDL', 'vcom')
+}
+
+
+def bug(issue_no, hdl='all'):
+    if hdl == 'all':
+        sims = list(chain.from_iterable(hdlmap.values()))
+    else:
+        sims = hdlmap[hdl]
+    return xfail(verify.simulator in sims, reason='issue '+issue_no)

myhdl/test/conversion/general/test_interfaces3.py

@@ -11,8 +11,7 @@ from myhdl.conversion import analyze, verify
 
 from myhdl import *
 
-xfail_ghdl = pytest.mark.xfail(verify.simulator == 'GHDL',
-                               reason='issue #33')
+from conftest import bug
 
 class Intf1:
     def __init__(self, x):
@@ -189,7 +188,7 @@ def test_three_analyze():
     intf = IntfWithConstant2()
     analyze(m_top_const, clock, reset, x, y, intf)
 
-@xfail_ghdl
+@bug('33', 'vhdl')
 def test_three_verify():
     assert verify(c_testbench_three) == 0