fix(core): Add stage prefix to stack name shortening process

packages/@aws-cdk/core/lib/private/unique-resource-name.ts

@@ -46,7 +46,7 @@ const MAX_LEN = 256;
 
 const HASH_LEN = 8;
 
-export function makeUniqueResourceName(components: string[], options: MakeUniqueResourceNameOptions) {
+export function makeUniqueResourceName(components: string[], options: MakeUniqueResourceNameOptions, prefix: string='') {
   const maxLength = options.maxLength ?? 256;
   const separator = options.separator ?? '';
   components = components.filter(x => x !== HIDDEN_ID);
@@ -59,7 +59,7 @@ export function makeUniqueResourceName(components: string[], options: MakeUnique
   // in order to support transparent migration of cloudformation templates to the CDK without the
   // need to rename all resources.
   if (components.length === 1) {
-    const topLevelResource = removeNonAllowedSpecialCharacters(components[0], separator, options.allowedSpecialCharacters);
+    const topLevelResource = prefix + removeNonAllowedSpecialCharacters(components[0], separator, options.allowedSpecialCharacters);
 
     if (topLevelResource.length <= maxLength) {
       return topLevelResource;
@@ -68,6 +68,9 @@ export function makeUniqueResourceName(components: string[], options: MakeUnique
 
   // Calculate the hash from the full path, included unresolved tokens so the hash value is always unique
   const hash = pathHash(components);
+  if (prefix) {
+    components.unshift(prefix);
+  }
   const human = removeDupes(components)
     .filter(pathElement => pathElement !== HIDDEN_FROM_HUMAN_ID)
     .map(pathElement => removeNonAllowedSpecialCharacters(pathElement, separator, options.allowedSpecialCharacters))

packages/@aws-cdk/core/lib/stack.ts

@@ -1424,7 +1424,7 @@ export class Stack extends Construct implements ITaggable {
   private generateStackName() {
     const assembly = Stage.of(this);
     const prefix = (assembly && assembly.stageName) ? `${assembly.stageName}-` : '';
-    return `${prefix}${this.generateStackId(assembly)}`;
+    return `${this.generateStackId(assembly, prefix)}`;
   }
 
   /**
@@ -1439,7 +1439,7 @@ export class Stack extends Construct implements ITaggable {
   /**
    * Generate an ID with respect to the given container construct.
    */
-  private generateStackId(container: IConstruct | undefined) {
+  private generateStackId(container: IConstruct | undefined, prefix: string='') {
     const rootPath = rootPathTo(this, container);
     const ids = rootPath.map(c => Node.of(c).id);
 
@@ -1449,7 +1449,7 @@ export class Stack extends Construct implements ITaggable {
       throw new Error('unexpected: stack id must always be defined');
     }
 
-    return makeStackName(ids);
+    return makeStackName(ids, prefix);
   }
 
   private resolveExportedValue(exportedValue: any): ResolvedExport {
@@ -1635,9 +1635,9 @@ export function rootPathTo(construct: IConstruct, ancestor?: IConstruct): IConst
  * has only one component. Otherwise we fall back to the regular "makeUniqueId"
  * behavior.
  */
-function makeStackName(components: string[]) {
-  if (components.length === 1) { return components[0]; }
-  return makeUniqueResourceName(components, { maxLength: 128 });
+function makeStackName(components: string[], prefix: string='') {
+  if (components.length === 1 && prefix.length === 0) { return components[0]; }
+  return makeUniqueResourceName(components, { maxLength: 128 }, prefix);
 }
 
 function getCreateExportsScope(stack: Stack) {

packages/@aws-cdk/core/test/stage.test.ts

@@ -103,6 +103,17 @@ describe('stage', () => {
     expect(stack.stackName).toEqual('MyStage-MyStack');
   });
 
+  test('generated stack names will not exceed 128 characters', () => {
+    // WHEN
+    const app = new App();
+    const stage = new Stage(app, 'ThisStageNameIsVeryLongButWillOnlyBeTooLongWhenCombinedWithTheStackName');
+    const stack = new BogusStack(stage, 'ThisStackNameIsVeryLongButItWillOnlyBeTooLongWhenCombinedWithTheLongPrefix');
+
+    // THEN
+    expect(stack.stackName.length).toEqual(128);
+    expect(stack.stackName).toEqual('ThisStageNameIsVeryLongButWillOnlyBeTooLongWhenCombinedWithTsVeryLongButItWillOnlyBeTooLongWhenCombinedWithTheLongPrefix4CA9F65B');
+  });
+
   test('Can not have dependencies to stacks outside the nested asm', () => {
     // GIVEN
     const app = new App();