Fix: handle infinite loop caused by get traceState() (#530)

Author: mayurkale22

packages/opencensus-core/src/trace/model/no-record/no-record-span.ts

@@ -87,7 +87,7 @@ export class NoRecordSpan implements types.Span {
 
   /** Gets the trace state */
   get traceState(): types.TraceState|undefined {
-    return this.root.traceState;
+    return undefined;
   }
 
   /** Gets the ID of the parent span. */

packages/opencensus-core/test/test-no-record-root-span.ts

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+import * as assert from 'assert';
 import {CanonicalCode, CoreTracer, LinkType, MessageEventType, SpanKind} from '../src';
 import {NoRecordRootSpan} from '../src/trace/model/no-record/no-record-root-span';
 
@@ -32,5 +33,6 @@ describe('NoRecordRootSpan()', () => {
     noRecordRootSpan.addAttribute('my_first_attribute', 'foo');
     noRecordRootSpan.setStatus(CanonicalCode.OK);
     noRecordRootSpan.startChildSpan();
+    assert.equal(noRecordRootSpan.traceState, undefined);
   });
 });

packages/opencensus-core/test/test-no-record-span.ts

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+import * as assert from 'assert';
 import {CanonicalCode, LinkType, MessageEventType} from '../src';
 import {NoRecordSpan} from '../src/trace/model/no-record/no-record-span';
 
@@ -28,5 +29,6 @@ describe('NoRecordSpan()', () => {
     noRecordSpan.addMessageEvent(MessageEventType.RECEIVED, 1, 123456789);
     noRecordSpan.addAttribute('my_first_attribute', 'foo');
     noRecordSpan.setStatus(CanonicalCode.OK);
+    assert.equal(noRecordSpan.traceState, undefined);
   });
 });

packages/opencensus-core/test/test-root-span.ts

@@ -324,4 +324,19 @@ describe('RootSpan', () => {
       assert.ok(instanceOfLink(rootSpan.messageEvents[0]));
     });
   });
+
+  describe('get traceState()', () => {
+    it('should handle optional / undefined traceState', () => {
+      const root = new RootSpan(tracer, name, kind, traceId, parentSpanId);
+      assert.ok(root instanceof RootSpan);
+      assert.equal(root.traceState, undefined);
+    });
+
+    it('should create a RootSpan instance with traceState', () => {
+      const root =
+          new RootSpan(tracer, name, kind, traceId, parentSpanId, 'traceState');
+      assert.ok(root instanceof RootSpan);
+      assert.equal(root.traceState, 'traceState');
+    });
+  });
 });

packages/opencensus-core/test/test-span.ts

@@ -370,4 +370,27 @@ describe('Span', () => {
       assert.equal(span.status.message, 'This is an error');
     });
   });
+
+  describe('get traceState()', () => {
+    it('should return the traceState', () => {
+      const rootSpan =
+          new RootSpan(tracer, name, kind, traceId, parentSpanId, 'traceState');
+      rootSpan.start();
+      assert.equal(rootSpan.traceState, 'traceState');
+
+      const span = new Span(tracer, rootSpan);
+      assert.equal(span.traceId, rootSpan.traceId);
+      assert.equal(span.traceState, 'traceState');
+    });
+
+    it('should handle optional / undefined traceState', () => {
+      const rootSpan = new RootSpan(tracer, name, kind, traceId, parentSpanId);
+      rootSpan.start();
+      assert.equal(rootSpan.traceState, undefined);
+
+      const span = new Span(tracer, rootSpan);
+      assert.equal(span.traceId, rootSpan.traceId);
+      assert.equal(span.traceState, undefined);
+    });
+  });
 });