Add tests for global

Author: HyeockJinKim

tests/snippets/global_nonlocal.py

@@ -27,6 +27,14 @@ def y():
 res = x()
 assert res == 3, str(res)
 
+def x():
+    global a
+    global a # a here shouldn't generate SyntaxError
+    a = 3
+
+x()
+assert a == 3
+
 # Invalid syntax:
 src = """
 b = 2
@@ -44,7 +52,6 @@ def y():
 with assert_raises(SyntaxError):
     exec(src)
 
-
 # Invalid syntax:
 src = """
 def f():
@@ -62,6 +69,15 @@ def a():
     nonlocal a
 """
 
+with assert_raises(SyntaxError):
+    exec(src)
+
+src = """
+def f():
+    print(a)
+    global a
+"""
+
 with assert_raises(SyntaxError):
     exec(src)