Handle fractions

edn-format/edn#64
bfontaine · Aug 24, 2018 · eec8248 · eec8248
1 parent 7a3865c
commit eec8248
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Showing 4 changed files with 23 additions and 5 deletions.
diff --git a/edn_format/edn_dump.py b/edn_format/edn_dump.py
@@ -3,6 +3,7 @@
 
 import datetime
 import decimal
+import fractions
 import itertools
 import re
 import sys
@@ -105,6 +106,8 @@ def udump(obj,
             pairs = ((Keyword(k) if isinstance(k, (bytes, basestring)) else k, v) for k, v in pairs)
 
         return '{{{}}}'.format(seq(itertools.chain.from_iterable(pairs), **kwargs))
+    elif isinstance(obj, fractions.Fraction):
+        return str(obj)
     elif isinstance(obj, datetime.datetime):
         return '#inst "{}"'.format(pyrfc3339.generate(obj, microseconds=True))
     elif isinstance(obj, datetime.date):

diff --git a/edn_format/edn_lex.py b/edn_format/edn_lex.py
@@ -93,6 +93,7 @@ def __str__(self):
           'BOOLEAN',
           'INTEGER',
           'FLOAT',
+          'DIVIDE',
           'SYMBOL',
           'KEYWORD',
           'VECTOR_START',
@@ -124,8 +125,6 @@ def __str__(self):
           r"\/"
           "[{all}]+"
           "|"
-          r"\/"
-          "|"
           "{start}"
           "[{all}]*"
           ")").format(**PARTS)
@@ -147,6 +146,7 @@ def __str__(self):
        "[{all}]*"
        ")").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
@@ -2,6 +2,7 @@
 from __future__ import absolute_import, division, print_function, unicode_literals
 
 import datetime
+import fractions
 import sys
 import uuid
 
@@ -52,7 +53,8 @@ def p_term_leaf(p):
             | NIL
             | KEYWORD
             | SYMBOL
-            | WHITESPACE"""
+            | WHITESPACE
+            | DIVIDE"""
     p[0] = p[1]
 
 
@@ -91,6 +93,11 @@ 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]
@@ -115,6 +122,7 @@ def p_expression(p):
                   | list
                   | set
                   | map
+                  | fraction
                   | term"""
     p[0] = p[1]
 

diff --git a/tests.py b/tests.py
@@ -6,8 +6,8 @@
 from uuid import uuid4
 import random
 import datetime
+import fractions
 import unittest
-
 import pytz
 
 from edn_format import edn_lex, edn_parse, \
@@ -58,14 +58,15 @@ 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(MAP_START,'{',1,0), "
                        "LexToken(KEYWORD,Keyword(a),1,2), "
                        "LexToken(BOOLEAN,False,1,5), "
@@ -74,6 +75,11 @@ def test_lexer(self):
                        "LexToken(MAP_OR_SET_END,'}',1,21)]",
                        "{ :a false, :b false }")
 
+        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))
 
@@ -129,6 +135,7 @@ def test_parser(self):
         self.check_parse(frozenset({ImmutableList([u"ab", u"cd"]),
                                     ImmutableList([u"ef"])}),
                          '#{["ab", "cd"], ["ef"]}')
+        self.check_parse(fractions.Fraction(2, 3), "2/3")
 
     def check_roundtrip(self, data_input, **kw):
         self.assertEqual(data_input, loads(dumps(data_input, **kw)))