add parsing of constant with unary +

2 files changed, 16 insertions, 1 deletions

diff --git a/cffi/cparser.py b/cffi/cparser.py
index a53d4c3..d699894 100644
--- a/cffi/cparser.py
+++ b/cffi/cparser.py
@@ -532,11 +532,15 @@ class Parser(object):
 
     def _parse_constant(self, exprnode, partial_length_ok=False):
         # for now, limited to expressions that are an immediate number
-        # or negative number
+        # or positive/negative number
         if isinstance(exprnode, pycparser.c_ast.Constant):
             return int(exprnode.value, 0)
         #
         if (isinstance(exprnode, pycparser.c_ast.UnaryOp) and
+                exprnode.op == '+'):
+            return self._parse_constant(exprnode.expr)
+        #
+        if (isinstance(exprnode, pycparser.c_ast.UnaryOp) and
                 exprnode.op == '-'):
             return -self._parse_constant(exprnode.expr)
         # load previously defined int constant
diff --git a/testing/test_parsing.py b/testing/test_parsing.py
index 594796a..97a16f9 100644
--- a/testing/test_parsing.py
+++ b/testing/test_parsing.py
@@ -288,3 +288,14 @@ def test__is_constant_globalvar():
         decl = ast.children()[0][1]
         node = decl.type
         assert p._is_constant_globalvar(node) == expected_output
+
+def test_enum():
+    ffi = FFI()
+    ffi.cdef("""
+        enum Enum { POS = +1, TWO = 2, NIL = 0, NEG = -1};
+        """)
+    C = ffi.dlopen(None)
+    assert C.POS == 1
+    assert C.TWO == 2
+    assert C.NIL == 0
+    assert C.NEG == -1