Merge pull request #6 from gregglind/negativearray-bug6

Negative array slicing?

3 files changed, 12 insertions, 8 deletions

diff --git a/jsonpath_rw/lexer.py b/jsonpath_rw/lexer.py
index d9efa50..9a70934 100644
--- a/jsonpath_rw/lexer.py
+++ b/jsonpath_rw/lexer.py
@@ -11,9 +11,9 @@ class JsonPathLexerError(Exception):
 
 class JsonPathLexer(object):
     '''
-    A Lexical analyzer for JsonPath. 
+    A Lexical analyzer for JsonPath.
     '''
-    
+
     def __init__(self, debug=False):
         self.debug = debug
         if self.__doc__ == None:
@@ -23,7 +23,7 @@ class JsonPathLexer(object):
         '''
         Maps a string to an iterator over tokens. In other words: [char] -> [token]
         '''
-        
+
         new_lexer = ply.lex.lex(module=self, debug=self.debug, errorlog=logger)
         new_lexer.latest_newline = 0
         new_lexer.input(string)
@@ -43,7 +43,7 @@ class JsonPathLexer(object):
     # Anyhow, it is pythonic to give some rope to hang oneself with :-)
 
     literals = ['*', '.', '[', ']', '(', ')', '$', ',', ':', '|', '&']
-    
+
     reserved_words = { 'where': 'WHERE' }
 
     tokens = ['DOUBLEDOT', 'NUMBER', 'ID', 'NAMED_OPERATOR'] + list(reserved_words.values())
@@ -62,7 +62,7 @@ class JsonPathLexer(object):
         return t
 
     def t_NUMBER(self, t):
-        r'\d+'
+        r'-?\d+'
         t.value = int(t.value)
         return t
 
@@ -101,7 +101,7 @@ class JsonPathLexer(object):
     def t_doublequote_error(self, t):
         raise JsonPathLexerError('Error on line %s, col %s while lexing doublequoted field: Unexpected character: %s ' % (t.lexer.lineno, t.lexpos - t.lexer.latest_newline, t.value[0]))
 
-    
+
     # Back-quoted "magic" operators
     t_backquote_ignore = ''
     def t_BACKQUOTE(self, t):
diff --git a/tests/test_lexer.py b/tests/test_lexer.py
index 115874f..64d26c9 100644
--- a/tests/test_lexer.py
+++ b/tests/test_lexer.py
@@ -15,7 +15,7 @@ class TestLexer(unittest.TestCase):
         t.lineno = -1
         t.lexpos = -1
         return t
-    
+
     def assert_lex_equiv(self, s, stream2):
         # NOTE: lexer fails to reset after call?
         l = JsonPathLexer(debug=True)
@@ -38,6 +38,8 @@ class TestLexer(unittest.TestCase):
         self.assert_lex_equiv('fuzz', [self.token('fuzz', 'ID')])
         self.assert_lex_equiv('1', [self.token(1, 'NUMBER')])
         self.assert_lex_equiv('45', [self.token(45, 'NUMBER')])
+        self.assert_lex_equiv('-1', [self.token(-1, 'NUMBER')])
+        self.assert_lex_equiv(' -13 ', [self.token(-13, 'NUMBER')])
         self.assert_lex_equiv('"fuzz.bang"', [self.token('fuzz.bang', 'ID')])
         self.assert_lex_equiv('fuzz.bang', [self.token('fuzz', 'ID'), self.token('.', '.'), self.token('bang', 'ID')])
         self.assert_lex_equiv('fuzz.*', [self.token('fuzz', 'ID'), self.token('.', '.'), self.token('*', '*')])
diff --git a/tests/test_parser.py b/tests/test_parser.py
index ed41966..fd1e121 100644
--- a/tests/test_parser.py
+++ b/tests/test_parser.py
@@ -28,7 +28,9 @@ class TestParser(unittest.TestCase):
                                 ('[:]', Slice()),
                                 ('[*]', Slice()),
                                 ('[:2]', Slice(end=2)),
-                                ('[1:2]', Slice(start=1, end=2))])
+                                ('[1:2]', Slice(start=1, end=2)),
+                                ('[5:-2]', Slice(start=5, end=-2))
+                               ])
 
     def test_nested(self):
         self.check_parse_cases([('foo.baz', Child(Fields('foo'), Fields('baz'))),