Add tests for private claims in the payload

This change adds tests for private claims added to the payload during
sign and ensures that after verifying the payload contains the expected
claim.

test/claim-private.tests.js

@@ -0,0 +1,73 @@
+'use strict';
+
+const expect = require('chai').expect;
+const util = require('util');
+const testUtils = require('./test-utils');
+
+function signWithPayload(payload, callback) {
+  testUtils.signJWTHelper(payload, 'secret', {algorithm: 'none'}, callback);
+}
+
+describe('with a private claim', function() {
+  [
+    true,
+    false,
+    null,
+    -1,
+    0,
+    1,
+    -1.1,
+    1.1,
+    '',
+    'private claim',
+    'UTF8 - José',
+    [],
+    ['foo'],
+    {},
+    {foo: 'bar'},
+  ].forEach((privateClaim) => {
+    it(`should sign and verify with claim of ${util.inspect(privateClaim)}`, function (done) {
+      signWithPayload({privateClaim}, (e1, token) => {
+        testUtils.verifyJWTHelper(token, undefined, {}, (e2, decoded) => {
+          testUtils.asyncCheck(done, () => {
+            expect(e1).to.be.null;
+            expect(e2).to.be.null;
+            expect(decoded).to.have.property('privateClaim').to.deep.equal(privateClaim);
+          });
+        })
+      });
+    });
+  });
+
+  // these values JSON.stringify to null
+  [
+    -Infinity,
+    Infinity,
+    NaN,
+  ].forEach((privateClaim) => {
+    it(`should sign and verify with claim of ${util.inspect(privateClaim)}`, function (done) {
+      signWithPayload({privateClaim}, (e1, token) => {
+        testUtils.verifyJWTHelper(token, undefined, {}, (e2, decoded) => {
+          testUtils.asyncCheck(done, () => {
+            expect(e1).to.be.null;
+            expect(e2).to.be.null;
+            expect(decoded).to.have.property('privateClaim', null);
+          });
+        })
+      });
+    });
+  });
+
+  // private claims with value undefined are not added to the payload
+  it(`should sign and verify with claim of undefined`, function (done) {
+    signWithPayload({privateClaim: undefined}, (e1, token) => {
+      testUtils.verifyJWTHelper(token, undefined, {}, (e2, decoded) => {
+        testUtils.asyncCheck(done, () => {
+          expect(e1).to.be.null;
+          expect(e2).to.be.null;
+          expect(decoded).to.not.have.property('privateClaim');
+        });
+      })
+    });
+  });
+});