Add a test for getPublicKeyBytesAsBigInteger() (#28)

Author: asbelsare

src/com/google/cose/OkpKey.java

@@ -43,6 +43,7 @@ public byte[] getPublicKeyBytes() {
   }
 
   public BigInteger getPublicKeyBytesAsBigInteger() {
+    byte[] publicKeyBytes = getPublicKeyBytes();
     // Reverse the bytes to get the correct big-endian representation.
     byte[] reversedBytes = new byte[publicKeyBytes.length];
     for (int i = 0; i < publicKeyBytes.length; i++) {

test/com/google/cose/OkpSigningKeyTest.java

@@ -73,6 +73,8 @@ public void testRoundTrip() throws CborException, CoseException {
 
     Assert.assertArrayEquals(keyId, rebuiltKey.getKeyId());
     Assert.assertArrayEquals(keyWithConstructor.serialize(), rebuiltKey.serialize());
+    Assert.assertEquals(keyWithConstructor.getPublicKeyBytesAsBigInteger(), 
+        rebuiltKey.getPublicKeyBytesAsBigInteger());
   }
 
   @Test
@@ -186,4 +188,12 @@ public void testOkpGeneratedKey_verificationWithSignature() throws CborException
 
     okpKey.verify(Algorithm.SIGNING_ALGORITHM_EDDSA, TestUtilities.CONTENT_BYTES, signature);
   }
+
+  @Test
+  public void testPublicKeyAsBigInteger() throws CborException, CoseException {
+    OkpSigningKey key = OkpSigningKey.builder().withXCoordinate(X_BYTES).build();
+    Assert.assertEquals(
+        "11903303657706407974989296177215005343713679411332034699907763981919547054807",
+        key.getPublicKeyBytesAsBigInteger().toString());
+  }
 }