added tests and better handle zero-length cookies

lib/controls/paged_results_control.js

@@ -50,6 +50,7 @@ PagedResultsControl.prototype.parse = function parse(buffer) {
     this._value = {};
     this._value.size = ber.readInt();
     this._value.cookie = ber.readString(asn1.Ber.OctetString, true);
+    if(!this._value.cookie) this._value.cookie = new Buffer(0); //readString returns '' instead of a zero-length buffer
     return true;
   }
 
@@ -66,10 +67,10 @@ PagedResultsControl.prototype._toBer = function (ber) {
   var writer = new BerWriter();
   writer.startSequence();
   writer.writeInt(this.value.size);
-  if(this.value.cookie)
+  if(this.value.cookie && this.value.cookie.length>0)
     writer.writeBuffer(this.value.cookie, asn1.Ber.OctetString);
   else
-    writer.writeString('');
+    writer.writeString(''); //writeBuffer rejects zero-length buffers
   writer.endSequence();
 
   ber.writeBuffer(writer.buffer, 0x04);

test/controls/paged_results_control_test.js

@@ -0,0 +1,86 @@
+
+var test = require('tap').test;
+
+var asn1 = require('asn1');
+
+var BerReader = asn1.BerReader;
+var BerWriter = asn1.BerWriter;
+var getControl;
+var PagedResultsControl;
+
+function bufferEqual(t, a, b) {
+  t.equal(a.toString('hex'), b.toString('hex'))
+}
+
+
+///--- Tests
+
+
+test('load library', function (t) {
+  PagedResultsControl =
+    require('../../lib').PagedResultsControl;
+  t.ok(PagedResultsControl);
+  getControl = require('../../lib').getControl;
+  t.ok(getControl);
+  t.end();
+});
+
+
+test('new no args', function (t) {
+  t.ok(new PagedResultsControl());
+  t.end();
+});
+
+
+test('new with args', function (t) {
+  var c = new PagedResultsControl({
+    type: '1.2.840.113556.1.4.319',
+    criticality: true,
+    value: {
+      size: 1000,
+      cookie: new Buffer([1,2,3])
+    }
+  });
+  t.ok(c);
+  t.equal(c.type, '1.2.840.113556.1.4.319');
+  t.ok(c.criticality);
+  t.equal(c.value.size, 1000);
+  bufferEqual(t,c.value.cookie, new Buffer([1,2,3]));
+
+
+  var writer = new BerWriter();
+  c.toBer(writer);
+  var reader = new BerReader(writer.buffer);
+  var psc = getControl(reader);
+  t.ok(psc);
+  console.log('psc', psc.value);
+  t.equal(psc.type, '1.2.840.113556.1.4.319');
+  t.ok(psc.criticality);
+  t.equal(psc.value.size, 1000);
+  bufferEqual(t,psc.value.cookie, new Buffer([1,2,3]));
+
+  t.end();
+});
+
+test('tober', function (t) {
+  var psc = new PagedResultsControl({
+    type: '1.2.840.113556.1.4.319',
+    criticality: true,
+    value: {
+      size: 20,
+      cookie: new Buffer(0)
+    }
+  });
+
+  var ber = new BerWriter();
+  psc.toBer(ber);
+
+  var c = getControl(new BerReader(ber.buffer));
+  t.ok(c);
+  t.equal(c.type, '1.2.840.113556.1.4.319');
+  t.ok(c.criticality);
+  t.equal(c.value.size, 20);
+  bufferEqual(t,c.value.cookie, new Buffer(0));
+
+  t.end();
+});