added raise statements

tests/test_parser.py

@@ -513,6 +513,12 @@ def test_del_two_comma():
 def test_raise():
     yield check_stmts, 'raise', False
     
+def test_raise_x():
+    yield check_stmts, 'raise TypeError', False
+    
+def test_raise_x_from():
+    yield check_stmts, 'raise TypeError from x', False
+    
 
 #DEBUG_LEVEL = 1
 #DEBUG_LEVEL = 100

xonsh/ast.py

@@ -6,4 +6,4 @@ from ast import Module, Num, Expr, Str, Bytes, UnaryOp, UAdd, USub, Invert, \
     Index, Load, Slice, List, Tuple, Set, Dict, AST, NameConstant, Ellipsis, \
     Name, GeneratorExp, Store, comprehension, ListComp, SetComp, DictComp, \
     Assign, AugAssign, BitXor, BitAnd, BitOr, LShift, RShift, Assert, Delete, \
-    Del, Pass
+    Del, Pass, Raise

xonsh/parser.py

@@ -559,10 +559,23 @@ class Parser(object):
 
     def p_raise_stmt(self, p):
         """raise_stmt : RAISE 
-                      | test 
-                      | test FROM test
+                      | RAISE test 
+                      | RAISE test FROM test
         """
-        p[0] = p[1:]
+        lenp = len(p)
+        cause = None
+        if lenp == 2:
+            exc = None
+        elif lenp == 3:
+            exc = p[2]
+        elif lenp == 5:
+            exc = p[2]
+            cause = p[4]
+        else:
+            assert False
+        p0 = ast.Raise(exc=exc, cause=cause, lineno=self.lineno, 
+                       col_offset=self.col)
+        p[0] = p0
 
     def p_import_stmt(self, p):
         """import_stmt : import_name