Update handling of non-finite numbers to match jq 1.6

3 files changed, 37 insertions, 2 deletions

diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 2bba698..bfb2984 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -1,6 +1,13 @@
 Changelog
 =========
 
+1.4.0
+-----
+
+* Update handling of non-finite numbers to match the behaviour jq 1.6.
+  Specifically, NaN is outputted as None, Inf is outputted as DBL_MAX,
+  and -Inf is outputted as DBL_MIN.
+
 1.3.0
 -----
 
diff --git a/jq.pyx b/jq.pyx
index 00609a8..691b783 100644
--- a/jq.pyx
+++ b/jq.pyx
@@ -2,7 +2,8 @@ import json
 import threading
 
 from cpython.bytes cimport PyBytes_AsString
-from libc.math cimport modf
+from libc.float cimport DBL_MAX
+from libc.math cimport INFINITY, modf
 
 
 cdef extern from "jv.h":
@@ -83,7 +84,13 @@ cdef object _jv_to_python(jv value):
         python_value = True
     elif kind == JV_KIND_NUMBER:
         number_value = jv_number_value(value)
-        if _is_integer(number_value):
+        if number_value == INFINITY:
+            python_value = DBL_MAX
+        elif number_value == -INFINITY:
+            python_value = -DBL_MAX
+        elif number_value != number_value:
+            python_value = None
+        elif _is_integer(number_value):
             python_value = int(number_value)
         else:
             python_value = number_value
diff --git a/tests/jq_tests.py b/tests/jq_tests.py
index 4eab9f7..bcacdca 100644
--- a/tests/jq_tests.py
+++ b/tests/jq_tests.py
@@ -20,6 +20,27 @@ def test_can_add_one_to_each_element_of_an_array():
     )
 
 
+def test_nan_is_outputted_as_null():
+    assert_equal(
+        None,
+        jq.compile("0/0").input(0).first(),
+    )
+
+
+def test_positive_infinity_is_outputted_as_positive_max_double():
+    assert_equal(
+        1.7976931348623157e+308,
+        jq.compile(". * 2").input(1.7976931348623157e+308).first(),
+    )
+
+
+def test_negative_infinity_is_outputted_as_negative_max_double():
+    assert_equal(
+        -1.7976931348623157e+308,
+        jq.compile(". * 2").input(-1.7976931348623157e+308).first(),
+    )
+
+
 def test_can_use_regexes():
     assert_equal(
         True,