Handle fractions

edn-format/edn#64
swaroopch · Jun 23, 2014 · 958b84f · 958b84f
1 parent a3e80ff
commit 958b84f
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Showing 4 changed files with 21 additions and 4 deletions.
diff --git a/edn_format/edn_dump.py b/edn_format/edn_dump.py
@@ -3,6 +3,7 @@
 import decimal
 import datetime
 import uuid
+import fractions
 import pyrfc3339
 from .immutable_dict import ImmutableDict
 
@@ -43,6 +44,8 @@ def seq(obj):
         return "#{{{}}}".format(seq(obj))
     elif isinstance(obj, dict) or isinstance(obj, ImmutableDict):
         return "{{{}}}".format(seq(itertools.chain.from_iterable(obj.items())))
+    elif isinstance(obj, fractions.Fraction):
+        return str(obj)
     elif isinstance(obj, datetime.datetime):
         return '#inst "{}"'.format(pyrfc3339.generate(obj))
     elif isinstance(obj, datetime.date):

diff --git a/edn_format/edn_lex.py b/edn_format/edn_lex.py
@@ -58,6 +58,7 @@ def __str__(self):
           'BOOLEAN',
           'INTEGER',
           'FLOAT',
+          'DIVIDE',
           'SYMBOL',
           'KEYWORD',
           'VECTOR_START',
@@ -89,8 +90,6 @@ def __str__(self):
           r"\/"
           r"[{all}]+"
           r"|"
-          r"\/"
-          r"|"
           r"{start}"
           r"[{all}]*"
           r")").format(**PARTS)
@@ -112,6 +111,7 @@ def __str__(self):
        r"[{all}]*"
        r")").format(**PARTS)
 
+t_DIVIDE = r'\/'
 t_VECTOR_START = r'\['
 t_VECTOR_END = r'\]'
 t_LIST_START = r'\('

diff --git a/edn_format/edn_parse.py b/edn_format/edn_parse.py
@@ -3,6 +3,7 @@
 import sys
 import uuid
 import datetime
+import fractions
 import pyrfc3339
 
 import ply.yacc
@@ -50,7 +51,8 @@ def p_term_leaf(p):
             | NIL
             | KEYWORD
             | SYMBOL
-            | WHITESPACE"""
+            | WHITESPACE
+            | DIVIDE"""
     p[0] = p[1]
 
 
@@ -89,6 +91,11 @@ def p_empty_map(p):
     p[0] = ImmutableDict({})
 
 
+def p_fraction(p):
+    """fraction : INTEGER DIVIDE INTEGER"""
+    p[0] = fractions.Fraction(p[1], p[3])
+
+
 def p_map(p):
     """map : MAP_START expressions MAP_OR_SET_END"""
     terms = p[2]
@@ -113,6 +120,7 @@ def p_expression(p):
                   | list
                   | set
                   | map
+                  | fraction
                   | term"""
     p[0] = p[1]
 

diff --git a/tests.py b/tests.py
@@ -1,4 +1,5 @@
 import datetime
+import fractions
 import pytz
 import unittest
 from edn_format import edn_lex, edn_parse, \
@@ -48,14 +49,18 @@ def test_lexer(self):
                        "abc")
         self.check_lex("[LexToken(SYMBOL,Symbol(?abc),1,0)]",
                        "?abc")
-        self.check_lex("[LexToken(SYMBOL,Symbol(/),1,0)]",
+        self.check_lex("[LexToken(DIVIDE,'/',1,0)]",
                        "/")
         self.check_lex("[LexToken(SYMBOL,Symbol(prefix/name),1,0)]",
                        "prefix/name")
         self.check_lex("[LexToken(SYMBOL,Symbol(true.),1,0)]",
                        "true.")
         self.check_lex("[LexToken(SYMBOL,Symbol($:ABC?),1,0)]",
                        "$:ABC?")
+        self.check_lex(("[LexToken(INTEGER,2,1,0), "
+                        "LexToken(DIVIDE,'/',1,1), "
+                        "LexToken(INTEGER,3,1,2)]"),
+                       "2/3")
 
     def check_parse(self, expected_output, actual_input):
         self.assertEqual(expected_output, edn_parse.parse(actual_input))
@@ -106,6 +111,7 @@ def test_parser(self):
         self.check_parse("blah\n", '"blah\n"')
         self.check_parse(["abc", "123"], '["abc", "123"]')
         self.check_parse({"key": "value"}, '{"key" "value"}')
+        self.check_parse(fractions.Fraction(2, 3), "2/3")
 
     def check_roundtrip(self, data_input):
         self.assertEqual(data_input, loads(dumps(data_input)))