Update integration test

packages/@aws-cdk/aws-pipes-targets-alpha/lib/cloudwatch-logs.ts

@@ -10,23 +10,23 @@ export interface CloudWatchLogsTargetParameters {
    * The input transformation to apply to the message before sending it to the target.
    *
    * @see https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-pipes-pipe-pipetargetparameters.html#cfn-pipes-pipe-pipetargetparameters-inputtemplate
-   * @default none
+   * @default - none
    */
   readonly inputTransformation?: IInputTransformation;
 
   /**
    * The name of the log stream.
    *
    * @see https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-pipes-pipe-pipetargetcloudwatchlogsparameters.html#cfn-pipes-pipe-pipetargetcloudwatchlogsparameters-logstreamname
-   * @default none
+   * @default - none
    */
   readonly logStreamName?: string;
 
   /**
    * The time the event occurred, expressed as the number of milliseconds after Jan 1, 1970 00:00:00 UTC.
    *
    * @see https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-pipes-pipe-pipetargetcloudwatchlogsparameters.html#cfn-pipes-pipe-pipetargetcloudwatchlogsparameters-timestamp
-   * @default none
+   * @default - none
    */
   readonly timestamp?: string;
 }
@@ -42,10 +42,13 @@ export class CloudWatchLogsTarget implements ITarget {
   constructor(logGroup: ILogGroup, parameters?: CloudWatchLogsTargetParameters) {
     this.logGroup = logGroup;
     this.targetArn = logGroup.logGroupArn;
-    this.cloudWatchLogsParameters = parameters;
 
-    validateLogStreamName(this.cloudWatchLogsParameters?.logStreamName);
-    validateTimestamp(this.cloudWatchLogsParameters?.timestamp);
+    if (parameters) {
+      this.cloudWatchLogsParameters = parameters;
+      for (const validate of [validateLogStreamName, validateTimestamp]) {
+        validate(parameters);
+      }
+    }
   }
 
   grantPush(grantee: IRole): void {
@@ -68,15 +71,15 @@ export class CloudWatchLogsTarget implements ITarget {
   }
 }
 
-function validateLogStreamName(name?: string) {
-  if (name !== undefined) {
-    if (name.length < 1 || name.length > 256) {
-      throw new Error(`Log stream name must be between 1 and 256 characters, received ${name.length}`);
+function validateLogStreamName({ logStreamName }: CloudWatchLogsTargetParameters) {
+  if (logStreamName !== undefined) {
+    if (logStreamName.length < 1 || logStreamName.length > 256) {
+      throw new Error(`Log stream name must be between 1 and 256 characters, received ${logStreamName.length}`);
     }
   }
 }
 
-function validateTimestamp(timestamp?: string) {
+function validateTimestamp({ timestamp }: CloudWatchLogsTargetParameters) {
   if (timestamp !== undefined) {
     if (timestamp.length < 1 || timestamp.length > 256) {
       throw new Error(`Timestamp must be between 1 and 256 characters, received ${timestamp.length}`);