Support PEP 3104, Access to Names in Outer Scopes

baron/formatting_grouper.py

@@ -87,6 +87,7 @@ class UnExpectedSpaceToken(BaronError):
     "RAISE",
     "EXEC",
     "GLOBAL",
+    "NONLOCAL",
     "PRINT",
     "INDENT",
     "WHILE",

baron/grammator.py

@@ -132,6 +132,7 @@ def simple_stmt_semicolon(pack):
     @pg.production("small_stmt : assert_stmt")
     @pg.production("small_stmt : raise_stmt")
     @pg.production("small_stmt : global_stmt")
+    @pg.production("small_stmt : nonlocal_stmt")
     @pg.production("compound_stmt : if_stmt")
     @pg.production("compound_stmt : while_stmt")
     @pg.production("compound_stmt : for_stmt")

baron/grammator_primitives.py

@@ -235,6 +235,16 @@ def global_stmt(pack):
         }
 
 
+    @pg.production("nonlocal_stmt : NONLOCAL names")
+    def nonlocal_stmt(pack):
+        (token, names) = pack
+        return {
+            "type": "nonlocal",
+            "formatting": token.hidden_tokens_after,
+            "value": names,
+        }
+
+
     @pg.production("names : NAME")
     def names_name(pack):
         (name,) = pack

baron/render.py

@@ -504,7 +504,11 @@ def child_by_key(node, key):
             ("formatting", "second_formatting", "as"),
             ("key",        "as",                "as"),
         ],
-
+        "nonlocal": [
+            ("constant",    "nonlocal",         True),
+            ("formatting", "formatting",        True),
+            ("list",        "value",            True),
+        ],
         "del": [
             ("constant",   "del",               True),
             ("formatting", "formatting",        True),

baron/tokenizer.py

@@ -5,7 +5,7 @@
 class UnknowItem(BaronError):
     pass
 
-KEYWORDS = ("and", "as", "assert", "break", "class", "continue", "def", "del", "elif", "else", "except", "exec", "finally", "for", "from", "global", "if", "import", "in", "is", "lambda", "not", "or", "pass", "print", "raise", "return", "try", "while", "with", "yield")
+KEYWORDS = ("and", "as", "assert", "break", "class", "continue", "def", "del", "elif", "else", "except", "exec", "finally", "for", "from", "global", "nonlocal", "if", "import", "in", "is", "lambda", "not", "or", "pass", "print", "raise", "return", "try", "while", "with", "yield")
 
 TOKENS = (
     (r'[a-zA-Z_]\w*', 'NAME'),

tests/test_formatting_grouper.py

@@ -2547,6 +2547,18 @@ def test_global_two():
     ])
 
 
+def test_nonlocal():
+    "global a"
+    group([
+        ('NONLOCAL', 'nonlocal'),
+        ('SPACE', ' '),
+        ('NAME', 'a'),
+    ], [
+        ('NONLOCAL', 'nonlocal', [], [('SPACE', ' ')]),
+        ('NAME', 'a'),
+    ])
+
+
 def test_print():
     "print"
     group([