What problem does it solve? Writing reliable tests for AWS CDK infrastructure is tricky: synthesized CloudFormation templates contain non-deterministic values like asset hashes, and teams struggle to choose between snapshot tests and explicit property assertions, leading to flaky tests or missed security-critical misconfigurations. ## Core Features & Use Cases - Snapshot Testing with Normalization: Capture full stack baselines with Template.fromStack() while normalizing non-deterministic values like S3Key and SourceObjectKeys to prevent false failures. - Fine-Grained Assertions: Verify specific resource properties using hasResourceProperties, resourceCountIs, and Match helpers for security-critical settings like encryption, IAM, and dead-letter queues. - Decision Guidance: Clear rules for when to use snapshots versus assertions, plus naming conventions and anti-patterns to avoid. - Use Case: When adding a new SQS stack with a dead-letter queue, generate a snapshot test for the overall template plus an explicit assertion verifying RedrivePolicy maxReceiveCount, then update snapshots safely after intentional changes. ## Quick Start Ask the AI to write CDK tests for a new stack following the snapshot and assertion patterns in this skill.
