Forces iidy to wait for a terminal state when summarizing stack contents

For some reason, iidy is getting an in progress state when summarizing stack contents. It's possible this is just due to timing.
When we know we're going to be in a terminal state, we can just wait for a terminal status to be returned instead of accepting the in progress status.
It's not clear why this specifically happens with `UPDATE_COMPLETE_CLEANUP_IN_PROGRESS`, but it could be a special case for timing.

src/cfn/getStackDescription.ts

@@ -1,9 +1,18 @@
+import { TERMINAL } from './statusTypes';
+
 import * as _ from 'lodash';
 import * as aws from 'aws-sdk'
 
-export async function getStackDescription(StackName: string): Promise<aws.CloudFormation.Stack> {
+export async function getStackDescription(StackName: string, expectTerminalStatus: boolean = false): Promise<aws.CloudFormation.Stack> {
   const cfn = new aws.CloudFormation();
-  const stacks = await cfn.describeStacks({StackName}).promise();
+  const stacks = await (async () => {
+    if (expectTerminalStatus) {
+      while (!_.includes(TERMINAL, (await cfn.describeStacks({StackName}).promise()).Stacks![0].StackStatus)) {
+        await new Promise(resolve => setTimeout(resolve, 1000));
+      }
+    }
+    return await cfn.describeStacks({StackName}).promise();
+  })();
   if (_.isUndefined(stacks.Stacks) || stacks.Stacks.length < 1) {
     throw new Error(`${StackName} not found. Has it been deleted? Check the AWS Console.`);
   } else {

src/cfn/index.ts

@@ -40,7 +40,7 @@ class CreateStack extends AbstractCloudFormationStackCommand {
 
 class UpdateStack extends AbstractCloudFormationStackCommand {
   cfnOperation: CfnOperation = 'UPDATE_STACK';
-  expectedFinalStackStatus = ['UPDATE_COMPLETE', 'UPDATE_COMPLETE_CLEANUP_IN_PROGRESS'];
+  expectedFinalStackStatus = ['UPDATE_COMPLETE'];
 
   async _run() {
     return this._runUpdate();
@@ -130,7 +130,7 @@ export class CreateChangeSet extends AbstractCloudFormationStackCommand {
 
 class ExecuteChangeSet extends AbstractCloudFormationStackCommand {
   cfnOperation: CfnOperation = 'EXECUTE_CHANGESET'
-  expectedFinalStackStatus = ['UPDATE_COMPLETE', 'UPDATE_COMPLETE_CLEANUP_IN_PROGRESS', 'CREATE_COMPLETE']
+  expectedFinalStackStatus = ['UPDATE_COMPLETE', 'CREATE_COMPLETE']
 
   async _run() {
     await this.cfn.executeChangeSet(

src/cfn/summarizeStackContents.ts

@@ -26,7 +26,7 @@ export async function summarizeStackContents(
   const resourcesPromise = cfn.describeStackResources({StackName: StackId}).promise();
   const exportsPromise = getAllStackExportsWithImports(StackId);
   const changeSetsPromise = cfn.listChangeSets({StackName: StackId}).promise();
-  const stack = await (stackPromise || getStackDescription(StackId));
+  const stack = await (stackPromise || getStackDescription(StackId, true));
   const resources = def([], (await resourcesPromise).StackResources);
   // TODO paginate resource lookup ^
   if (resources.length > 0) {