test: use a record-only sampler for test

packages/opentelemetry-tracing/test/common/export/BatchSpanProcessorBase.test.ts

@@ -16,7 +16,6 @@
 
 import { diag } from '@opentelemetry/api';
 import {
-  AlwaysOffSampler,
   AlwaysOnSampler,
   ExportResultCode,
   loggingErrorHandler,
@@ -26,6 +25,7 @@ import * as assert from 'assert';
 import * as sinon from 'sinon';
 import { BasicTracerProvider, BufferConfig, InMemorySpanExporter, Span } from '../../../src';
 import { context } from '@opentelemetry/api';
+import { TestRecordOnlySampler } from './TestRecordOnlySampler';
 import { TestTracingSpanExporter } from './TestTracingSpanExporter';
 import { TestStackContextManager } from './TestStackContextManager';
 import { BatchSpanProcessorBase } from '../../../src/export/BatchSpanProcessorBase';
@@ -41,7 +41,7 @@ function createSampledSpan(spanName: string): Span {
 
 function createUnsampledSpan(spanName: string): Span {
   const tracer = new BasicTracerProvider({
-    sampler: new AlwaysOffSampler(),
+    sampler: new TestRecordOnlySampler(),
   }).getTracer('default');
   const span = tracer.startSpan(spanName);
   span.end();

packages/opentelemetry-tracing/test/common/export/TestRecordOnlySampler.ts

@@ -0,0 +1,30 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { Sampler, SamplingDecision, SamplingResult } from '@opentelemetry/api';
+
+/** Sampler that always records but doesn't sample spans. */
+export class TestRecordOnlySampler implements Sampler {
+  shouldSample(): SamplingResult {
+    return {
+      decision: SamplingDecision.RECORD,
+    };
+  }
+
+  toString(): string {
+    return 'TestRecordOnlySampler';
+  }
+}