Add more tests for REAL

Author: andrivet

src/asn1.py

@@ -1008,7 +1008,7 @@ def _decode_real_binary(content):  # type: (bytes) -> float
             raise Error('ASN1 decoding error: Exponent ({}), mantissa ({}) or factor ({}) too big.'.format(exponent, mantissa, scaling))
         if value == 0:
             raise Error('ASN1 decoding error: invalid encoding for +0.')
-        return value
+        return float(value)  # Always as a float
 
     @staticmethod
     def _decode_real_binary_exponent(values):  # type: (bytes) -> Tuple[int, int]

tests/test_asn1.py

@@ -15,6 +15,7 @@
 import base64
 from builtins import int
 
+import math
 import pytest
 
 import asn1
@@ -422,6 +423,34 @@ def test_real(self):
         enc.write(0.15625)
         res = enc.output()
         assert res == b'\x09\x03\x80\xFB\x05'
+        enc.start()
+        enc.write(1.0)
+        res = enc.output()
+        assert res == b'\x09\x03\x80\x00\x01'
+        enc.start()
+        enc.write(-1.0)
+        res = enc.output()
+        assert res == b'\x09\x03\xC0\x00\x01'
+        enc.start()
+        enc.write(2.0)
+        res = enc.output()
+        assert res == b'\x09\x03\x80\x01\x01'
+        enc.start()
+        enc.write(0.5)
+        res = enc.output()
+        assert res == b'\x09\x03\x80\xFF\x01'
+        enc.start()
+        enc.write(10.5)
+        res = enc.output()
+        assert res == b'\x09\x03\x80\xFF\x15'
+        enc.start()
+        enc.write(-3.25)
+        res = enc.output()
+        assert res == b'\x09\x03\xC0\xFE\x0D'
+        enc.start()
+        enc.write(1024.0)
+        res = enc.output()
+        assert res == b'\x09\x03\x80\x0A\x01'
 
 class TestDecoder(object):
     """Test suite for ASN1 Decoder."""
@@ -1156,6 +1185,102 @@ def test_mix_context_universal(self):
 
         assert dec.peek() is None
 
+    def test_real_zero(self):
+        buf = b'\x09\x00'
+        enc = asn1.Decoder()
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == 0.0
+
+    def test_real_negative_zero(self):
+        buf = b'\x09\x01\x43'
+        enc = asn1.Decoder()
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == 0.0 and math.copysign(1, value) == -1.0
+
+    def test_real_negative_infinite(self):
+        buf = b'\x09\x01\x41'
+        enc = asn1.Decoder()
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == float('-inf')
+
+    def test_real_positive_infinite(self):
+        buf = b'\x09\x01\x40'
+        enc = asn1.Decoder()
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == float('inf')
+
+    def test_real_positive_nan(self):
+        buf = b'\x09\x01\x42'
+        enc = asn1.Decoder()
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value != value
+
+    def test_real(self):
+        buf = b'\x09\x03\x80\xFB\x05'
+        enc = asn1.Decoder()
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == 0.15625
+        buf = b'\x09\x03\x80\x00\x01'
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == 1.0
+        buf = b'\x09\x03\xC0\x00\x01'
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == -1.0
+        buf = b'\x09\x03\x80\x01\x01'
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == 2.0
+        buf = b'\x09\x03\x80\xFF\x01'
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == 0.5
+        buf = b'\x09\x03\x80\xFF\x15'
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == 10.5
+        buf = b'\x09\x03\xC0\xFE\x0D'
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == -3.25
+        buf = b'\x09\x03\x80\x0A\x01'
+        enc.start(buf)
+        tag, value = enc.read()
+        assert tag == (asn1.Numbers.Real, asn1.Types.Primitive, asn1.Classes.Universal)
+        assert isinstance(value, float)
+        assert value == 1024.0
+
 
 class TestEncoderDecoder(object):
     """Test suite for ASN1 Encoder and Decoder."""