From fc9a4ef6e9dcde7e48ca54609ba7c9e80a1f20a7 Mon Sep 17 00:00:00 2001
From: Oleg Broytman <phd@phdru.name>
Date: Sun, 22 Jun 2014 03:27:13 +0400
Subject: [PATCH] Change handling of spaces

AND/NOT/OR operators require spaces if subexpressions are not in
parentheses so ignoring whitespace no longer works.
---
 parser/grammar        | 16 ++++++++++------
 parser/parser.py      | 36 ++++++++++++++++++++++--------------
 parser/test_parser.py |  2 +-
 3 files changed, 33 insertions(+), 21 deletions(-)

diff --git a/parser/grammar b/parser/grammar
index 5a0c3d5..7c34096 100644
--- a/parser/grammar
+++ b/parser/grammar
@@ -26,9 +26,13 @@ NOT_OP : '!'
 SP1 : '[ \t]+'
 
 expression : NAME
-           | expression AND_OP AND_OP expression
-           | expression AND_OP expression
-           | expression OR_OP OR_OP expression
-           | expression OR_OP expression
-           | NOT_OP expression
-           | '(' expression ')'
+           | expression SP0 AND_OP AND_OP SP0 expression
+           | expression SP0 AND_OP SP0 expression
+           | NOT_OP SP0 expression
+           | expression SP0 OR_OP OR_OP SP0 expression
+           | expression SP0 OR_OP SP0 expression
+           | '(' SP0 expression SP0 ')'
+
+SP0 : SP1 | empty
+
+empty :
diff --git a/parser/parser.py b/parser/parser.py
index 1fb9903..0af77f6 100644
--- a/parser/parser.py
+++ b/parser/parser.py
@@ -4,7 +4,7 @@ from ply import lex, yacc
 
 literals = '()'
 
-tokens = ('NAME', 'AND_OP', 'OR_OP', 'NOT_OP')
+tokens = ('NAME', 'AND_OP', 'OR_OP', 'NOT_OP', 'SP1')
 
 t_NAME = '[a-z][a-z0-9_]*'
 
@@ -14,7 +14,7 @@ t_OR_OP = r'\|'
 
 t_NOT_OP = '!'
 
-t_ignore = '[ \t]+'
+t_SP1 = '[ \t]+'
 
 def t_error(t):
     """Avoid warnings on stderr"""
@@ -26,28 +26,36 @@ def p_expression_name(p):
     p[0] = ('NAME', p[1])
 
 def p_expression_and_and(p):
-    """expression : expression AND_OP AND_OP expression"""
-    p[0] = ('AND', p[1], p[4])
+    """expression : expression SP0 AND_OP AND_OP SP0 expression"""
+    p[0] = ('AND', p[1], p[6])
 
 def p_expression_and(p):
-    """expression : expression AND_OP expression"""
-    p[0] = ('AND', p[1], p[3])
+    """expression : expression SP0 AND_OP SP0 expression"""
+    p[0] = ('AND', p[1], p[5])
 
 def p_expression_not(p):
-    """expression : NOT_OP expression"""
-    p[0] = ('NOT', p[2])
+    """expression : NOT_OP SP0 expression"""
+    p[0] = ('NOT', p[3])
 
 def p_expression_or_or(p):
-    """expression : expression OR_OP OR_OP expression"""
-    p[0] = ('OR', p[1], p[4])
+    """expression : expression SP0 OR_OP OR_OP SP0 expression"""
+    p[0] = ('OR', p[1], p[6])
 
 def p_expression_or(p):
-    """expression : expression OR_OP expression"""
-    p[0] = ('OR', p[1], p[3])
+    """expression : expression SP0 OR_OP SP0 expression"""
+    p[0] = ('OR', p[1], p[5])
 
 def p_expression_parens(p):
-    """expression : '(' expression ')'"""
-    p[0] = ('PARENS', p[2])
+    """expression : '(' SP0 expression SP0 ')'"""
+    p[0] = ('PARENS', p[3])
+
+def p_SP0(p):
+    """SP0 : SP1
+           | empty
+    """
+
+def p_empty(p):
+    """empty : """
 
 def p_error(p):
     """Avoid warnings on stderr"""
diff --git a/parser/test_parser.py b/parser/test_parser.py
index 628c984..d7363c0 100755
--- a/parser/test_parser.py
+++ b/parser/test_parser.py
@@ -24,7 +24,7 @@ class TestParser(unittest.TestCase):
         self.assertEqual(parser.parse('!xxx&yyy&zzz|ooo'),
             ('OR', ('AND', ('AND', ('NOT', ('NAME', 'xxx')), ('NAME', 'yyy')), ('NAME', 'zzz')), ('NAME', 'ooo'))
         )
-        self.assertEqual(parser.parse('!(xxx && yyy)'),
+        self.assertEqual(parser.parse('!(xxx &&  yyy)'),
             ('NOT', ('PARENS', ('AND', ('NAME', 'xxx'), ('NAME', 'yyy'))))
         )
         self.assertEqual(parser.parse('!(xxx || yyy)'),
-- 
2.39.2