From ff2a072201fd4ec3cf1783e1ab0ecec6d3e7cb94 Mon Sep 17 00:00:00 2001
From: Dirk Pranke <dpranke@gmail.com>
Date: Sun, 14 May 2023 18:44:54 -0700
Subject: [PATCH] Fix GitHub issue #63 - Handle `+Infinity` properly.

The code handled `Infinity` and `-Infinity` but not `+Infinity`.
This change fixes that so all three are handled.
---
 json5/json5.g     |  3 ++-
 json5/parser.py   | 23 +++++++++++++----------
 tests/lib_test.py |  1 +
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/json5/json5.g b/json5/json5.g
index a33ccd2..2c5c05b 100644
--- a/json5/json5.g
+++ b/json5/json5.g
@@ -98,7 +98,8 @@ id_continue    = ascii_id_start
                | '\u200D'
 
 num_literal    = '-' num_literal:n                   -> '-' + n
-               | '+'? dec_literal:d ~id_start        -> d
+               | '+' num_literal:n                   -> n
+               | dec_literal:d ~id_start             -> d
                | hex_literal
                | 'Infinity'
                | 'NaN'
diff --git a/json5/parser.py b/json5/parser.py
index 86bc194..eb297fb 100644
--- a/json5/parser.py
+++ b/json5/parser.py
@@ -734,8 +734,8 @@ def _id_continue__c9_(self):
 
     def _num_literal_(self):
         self._choose([self._num_literal__c0_, self._num_literal__c1_,
-                      self._hex_literal_, self._num_literal__c3_,
-                      self._num_literal__c4_])
+                      self._num_literal__c2_, self._hex_literal_,
+                      self._num_literal__c4_, self._num_literal__c5_])
 
     def _num_literal__c0_(self):
         self._push('num_literal__c0')
@@ -746,19 +746,22 @@ def _num_literal__c0_(self):
 
     def _num_literal__c1_(self):
         self._push('num_literal__c1')
-        self._seq([self._num_literal__c1__s0_,
-                   lambda: self._bind(self._dec_literal_, 'd'),
-                   lambda: self._not(self._id_start_),
-                   lambda: self._succeed(self._get('d'))])
+        self._seq([lambda: self._ch('+'),
+                   lambda: self._bind(self._num_literal_, 'n'),
+                   lambda: self._succeed(self._get('n'))])
         self._pop('num_literal__c1')
 
-    def _num_literal__c1__s0_(self):
-        self._opt(lambda: self._ch('+'))
+    def _num_literal__c2_(self):
+        self._push('num_literal__c2')
+        self._seq([lambda: self._bind(self._dec_literal_, 'd'),
+                   lambda: self._not(self._id_start_),
+                   lambda: self._succeed(self._get('d'))])
+        self._pop('num_literal__c2')
 
-    def _num_literal__c3_(self):
+    def _num_literal__c4_(self):
         self._str('Infinity')
 
-    def _num_literal__c4_(self):
+    def _num_literal__c5_(self):
         self._str('NaN')
 
     def _dec_literal_(self):
diff --git a/tests/lib_test.py b/tests/lib_test.py
index 68842e7..90e5f56 100644
--- a/tests/lib_test.py
+++ b/tests/lib_test.py
@@ -120,6 +120,7 @@ def test_numbers(self):
 
         # names
         self.check('Infinity', float('inf'))
+        self.check('+Infinity', float('inf'))
         self.check('-Infinity', float('-inf'))
         self.assertTrue(math.isnan(json5.loads('NaN')))
         self.assertTrue(math.isnan(json5.loads('-NaN')))