chore: upgrade vitest & update coverage exceptions

package.json

@@ -53,7 +53,7 @@
     "@biomejs/biome": "^2.3.5",
     "@types/aws-lambda": "^8.10.158",
     "@types/node": "^24.10.1",
-    "@vitest/coverage-v8": "^3.2.4",
+    "@vitest/coverage-v8": "^4.0.9",
     "husky": "^9.1.7",
     "lint-staged": "^16.2.5",
     "markdownlint-cli2": "^0.19.0",
@@ -62,7 +62,7 @@
     "typedoc": "^0.28.14",
     "typedoc-plugin-missing-exports": "^4.1.2",
     "typescript": "^5.9.3",
-    "vitest": "^3.0.9"
+    "vitest": "^4.0.9"
   },
   "lint-staged": {
     "*.{js,ts,json}": "biome check --write --no-errors-on-unmatched",

packages/batch/src/BasePartialBatchProcessor.ts

@@ -117,6 +117,7 @@ abstract class BasePartialBatchProcessor extends BasePartialProcessor {
 
     for (const msg of this.failureMessages) {
       const msgId = (msg as DynamoDBRecord).dynamodb?.SequenceNumber;
+      /* v8 ignore else -- @preserve */
       if (msgId) {
         failures.push({ itemIdentifier: msgId });
       }

packages/batch/src/BatchProcessorSync.ts

@@ -82,13 +82,13 @@ import type { BaseRecord, FailureResponse, SuccessResponse } from './types.js';
  * @param eventType The type of event to process (SQS, Kinesis, DynamoDB)
  * @deprecated Use {@link BasePartialBatchProcessor} instead, this class is deprecated and will be removed in the next major version.
  */
-/* v8 ignore start */ class BatchProcessorSync extends BasePartialBatchProcessor {
+/* v8 ignore next -- @preserve */ class BatchProcessorSync extends BasePartialBatchProcessor {
   /**
    * @throws {BatchProcessingError} This method is not implemented for asynchronous processing.
    *
    * @param _record The record to be processed
    */
-  public processRecord(
+  /* v8 ignore next -- @preserve */ public processRecord(
     _record: BaseRecord
   ): Promise<SuccessResponse | FailureResponse> {
     throw new BatchProcessingError('Not implemented. Use process() instead.');
@@ -120,6 +120,6 @@ import type { BaseRecord, FailureResponse, SuccessResponse } from './types.js';
       return this.failureHandler(record, error as Error);
     }
   }
-} /* v8 ignore stop */
+}
 
 export { BatchProcessorSync };

packages/batch/src/processPartialResponseSync.ts

@@ -99,7 +99,7 @@ import type {
  * @param processor Batch processor instance to handle the batch processing
  * @param options Batch processing options, which can vary with chosen batch processor implementation
  */
-/* v8 ignore start */ const processPartialResponseSync = <
+/* v8 ignore next -- @preserve */ const processPartialResponseSync = <
   T extends BasePartialBatchProcessor,
 >(
   event: { Records: BaseRecord[] },
@@ -116,6 +116,6 @@ import type {
   processor.processSync();
 
   return processor.response();
-}; /* v8 ignore stop */
+};
 
 export { processPartialResponseSync };

packages/commons/src/LRUCache.ts

@@ -215,6 +215,7 @@ class LRUCache<K, V> {
     if (this.mostRecentlyUsed === item) return;
 
     // If the item is not the newest, we need to mark it as the newest
+    /* v8 ignore else -- @preserve */
     if (item[NEWER]) {
       if (item === this.leastRecentlyUsed) {
         this.leastRecentlyUsed = item[NEWER];
@@ -226,6 +227,7 @@ class LRUCache<K, V> {
     }
     item[NEWER] = undefined;
     item[OLDER] = this.mostRecentlyUsed;
+    /* v8 ignore else -- @preserve */
     if (this.mostRecentlyUsed) {
       this.mostRecentlyUsed[NEWER] = item;
     }

packages/commons/src/awsSdkUtils.ts

@@ -80,6 +80,7 @@ const customUserAgentMiddleware = (feature: string) => {
 const hasPowertools = (middlewareStack: string[]): boolean => {
   let found = false;
   for (const middleware of middlewareStack) {
+    /* v8 ignore else -- @preserve */
     if (middleware.includes('addPowertoolsToUserAgent')) {
       found = true;
     }

packages/event-handler/src/appsync-events/RouteHandlerRegistry.ts

@@ -115,6 +115,7 @@ class RouteHandlerRegistry {
       }
     }
     if (mostSpecificHandler === undefined) {
+      /* v8 ignore else -- @preserve */
       if (!this.#warningSet.has(path)) {
         this.#logger.warn(
           `No route handler found for path '${path}' registered for ${this.#eventType}.`

packages/event-handler/src/appsync-events/utils.ts

@@ -38,8 +38,8 @@ const isAppSyncEventsEvent = (event: unknown): event is AppSyncEventsEvent => {
     'name' in event.info.channelNamespace &&
     isString(event.info.channelNamespace.name) &&
     'operation' in event.info &&
-    /* v8 ignore next */
-    (event.info.operation === 'PUBLISH' || event.info.operation === 'SUBSCRIBE')
+    isString(event.info.operation) &&
+    ['PUBLISH', 'SUBSCRIBE'].includes(event.info.operation)
   );
 };
 

packages/event-handler/src/rest/converters.ts

@@ -322,6 +322,7 @@ function addProxyEventHeaders(
   response: ExtendedAPIGatewayProxyResult
 ) {
   for (const [key, value] of Object.entries(response.headers ?? {})) {
+    /* v8 ignore else -- @preserve */
     if (value != null) {
       headers.set(key, String(value));
     }

packages/event-handler/src/rest/middleware/cors.ts

@@ -111,6 +111,7 @@ export const cors = (options?: CorsOptions): Middleware => {
         return;
       }
       setCORSBaseHeaders(requestOrigin, reqCtx.res.headers);
+      /* v8 ignore else -- @preserve */
       if (config.maxAge !== undefined) {
         reqCtx.res.headers.set(
           'access-control-max-age',

packages/event-handler/src/rest/utils.ts

@@ -365,6 +365,7 @@ export const getBase64EncodingFromHeaders = (headers: Headers): boolean => {
   }
 
   const contentType = headers.get('content-type');
+  /* v8 ignore else -- @preserve */
   if (contentType != null) {
     const type = contentType.split(';')[0].trim();
     if (
@@ -400,6 +401,7 @@ const streamifyResponse =
     return (async (event, responseStream, context) => {
       await handler(event, responseStream, context);
 
+      /* v8 ignore else -- @preserve */
       if ('chunks' in responseStream && Array.isArray(responseStream.chunks)) {
         const output = Buffer.concat(responseStream.chunks as Buffer[]);
         const nullBytes = Buffer.from([0, 0, 0, 0, 0, 0, 0, 0]);

packages/event-handler/tests/unit/rest/Router/basic-routing.test.ts

@@ -144,13 +144,13 @@ describe.each([
     expect(actual.hasContext).toBe(true);
   });
 
-  it('throws an invalid event error for non-API Gateway events', () => {
+  it('throws an invalid event error for non-API Gateway events', async () => {
     // Prepare
     const app = new Router();
     const nonApiGatewayEvent = { Records: [] }; // SQS-like event
 
     // Act & Assess
-    expect(app.resolve(nonApiGatewayEvent, context)).rejects.toThrowError(
+    await expect(app.resolve(nonApiGatewayEvent, context)).rejects.toThrowError(
       InvalidEventError
     );
   });

packages/idempotency/src/middleware/makeHandlerIdempotent.ts

@@ -124,7 +124,7 @@ const makeHandlerIdempotent = (
     });
 
     const idempotencyHandler = new IdempotencyHandler({
-      functionToMakeIdempotent: /* v8 ignore next */ () => ({}),
+      functionToMakeIdempotent: /* v8 ignore next -- @preserve */ () => ({}),
       functionArguments: [],
       idempotencyConfig,
       persistenceStore,

packages/idempotency/src/persistence/BasePersistenceLayer.ts

@@ -226,6 +226,7 @@ abstract class BasePersistenceLayer implements BasePersistenceLayerInterface {
   private deleteFromCache(idempotencyKey: string): void {
     if (!this.useLocalCache) return;
     // Delete from local cache if it exists
+    /* v8 ignore else -- @preserve */
     if (this.cache?.has(idempotencyKey)) {
       this.cache?.remove(idempotencyKey);
     }
@@ -324,6 +325,7 @@ abstract class BasePersistenceLayer implements BasePersistenceLayerInterface {
     if (Array.isArray(data) || typeof data === 'object') {
       if (data === null) return true;
       for (const value of Object.values(data)) {
+        /* v8 ignore else -- @preserve */
         if (value) {
           return false;
         }

packages/idempotency/tests/unit/persistence/BasePersistenceLayer.test.ts

@@ -28,20 +28,17 @@ vi.mock('node:crypto', () => ({
 }));
 
 describe('Class: BasePersistenceLayer', () => {
-  const ENVIRONMENT_VARIABLES = process.env;
-
   beforeAll(() => {
     vi.useFakeTimers().setSystemTime(new Date());
   });
 
   beforeEach(() => {
     vi.clearAllMocks();
     vi.resetModules();
-    process.env = { ...ENVIRONMENT_VARIABLES };
+    vi.stubEnv('AWS_LAMBDA_FUNCTION_NAME', 'my-lambda-function');
   });
 
   afterAll(() => {
-    process.env = ENVIRONMENT_VARIABLES;
     vi.useRealTimers();
   });
 

packages/jmespath/src/Parser.ts

@@ -668,6 +668,7 @@ class Parser {
       const value = this.#expression(0);
       const node = keyValPair(keyName, value);
       pairs.push(node);
+      /* v8 ignore else -- @preserve */
       if (this.#currentToken() === 'comma') {
         this.#match('comma');
       } else if (this.#currentToken() === 'rbrace') {

packages/jmespath/src/TreeInterpreter.ts

@@ -144,6 +144,7 @@ class TreeInterpreter {
       if (comparator === 'ne') {
         return !isStrictEqual(left, right);
       }
+      /* v8 ignore else -- @preserve */
       if (typeof left === 'number' && typeof right === 'number') {
         // Ordering operators only work on numbers. Evaluating them on other
         // types will return null.
@@ -221,6 +222,7 @@ class TreeInterpreter {
       // @ts-expect-error
       return this.#functions[funcName](args);
     } catch (error) {
+      /* v8 ignore else -- @preserve */
       if (
         error instanceof JMESPathTypeError ||
         error instanceof VariadicArityError ||
@@ -372,6 +374,7 @@ class TreeInterpreter {
     }
     const collected: Record<string, JSONObject> = {};
     for (const child of node.children) {
+      /* v8 ignore else -- @preserve */
       if (typeof child.value === 'string') {
         collected[child.value] = this.visit(child, value);
       }

packages/jmespath/src/utils.ts

@@ -228,6 +228,7 @@ const checkIfArgumentTypeIsValid = (
 
     return true;
   }
+  /* v8 ignore else -- @preserve */
   if (['string', 'number', 'boolean'].includes(type)) {
     typeCheckType(arg, type, argumentSpec, hasMoreTypesToCheck);
     if (typeof arg === type) return true;

packages/kafka/src/consumer.ts

@@ -95,6 +95,7 @@ const deserialize = ({
     }
     return deserializer(value, config.schema);
   }
+  /* v8 ignore else -- @preserve */
   if (config.type === 'protobuf') {
     if (!config.schema) {
       throw new KafkaConsumerMissingSchemaError(
@@ -139,12 +140,11 @@ const getDeserializer = async (type?: string) => {
  */
 const parseSchema = (value: unknown, schema: StandardSchemaV1) => {
   const result = schema['~standard'].validate(value);
-  /* v8 ignore start */
+  /* v8 ignore next -- @preserve */
   if (result instanceof Promise)
     throw new KafkaConsumerParserError(
       'Schema parsing supports only synchronous validation'
     );
-  /* v8 ignore stop */
   if (result.issues) {
     throw new KafkaConsumerParserError('Schema validation failed', {
       cause: result.issues,

packages/logger/src/Logger.ts

@@ -519,7 +519,6 @@ class Logger extends Utility implements LoggerInterface {
             });
           }
           throw error;
-          /* v8 ignore next */
         } finally {
           if (options?.clearState || options?.resetKeys) loggerRef.resetKeys();
           loggerRef.clearBuffer();
@@ -531,28 +530,29 @@ class Logger extends Utility implements LoggerInterface {
   /**
    * @deprecated This method is deprecated and will be removed in the future major versions. Use {@link resetKeys()} instead.
    */
-  /* v8 ignore start */ public static injectLambdaContextAfterOrOnError(
+  /* v8 ignore next -- @preserve */
+  public static injectLambdaContextAfterOrOnError(
     logger: Logger,
     _persistentAttributes: LogAttributes,
     options?: InjectLambdaContextOptions
   ): void {
     if (options && (options.clearState || options?.resetKeys)) {
       logger.resetKeys();
     }
-  } /* v8 ignore stop */
+  }
 
   /**
    * @deprecated - This method is deprecated and will be removed in the next major version.
    */
-  /* v8 ignore start */ public static injectLambdaContextBefore(
+  /* v8 ignore next -- @preserve */ public static injectLambdaContextBefore(
     logger: Logger,
     event: unknown,
     context: Context,
     options?: InjectLambdaContextOptions
   ): void {
     logger.addContext(context);
     logger.logEventIfEnabled(event, options?.logEvent);
-  } /* v8 ignore stop */
+  }
 
   /**
    * Log the AWS Lambda event payload for the current invocation if the environment variable `POWERTOOLS_LOGGER_LOG_EVENT` is set to `true`.

packages/logger/src/logBuffer.ts

@@ -47,6 +47,7 @@ export class SizedSet<V> extends Set<SizedItem<V>> {
    */
   delete(item: SizedItem<V>): boolean {
     const wasDeleted = super.delete(item);
+    /* v8 ignore next -- @preserve */
     if (wasDeleted) {
       this.currentBytesSize -= item.byteSize;
     }
@@ -66,6 +67,7 @@ export class SizedSet<V> extends Set<SizedItem<V>> {
    */
   shift(): SizedItem<V> | undefined {
     const firstElement = this.values().next().value;
+    /* v8 ignore next -- @preserve */
     if (firstElement) {
       this.delete(firstElement);
     }

packages/metrics/src/Metrics.ts

@@ -604,6 +604,7 @@ class Metrics extends Utility implements MetricsInterface {
       );
     }
 
+    /* v8 ignore else -- @preserve */
     if (!this.disabled) {
       const emfOutput = this.serializeMetrics();
       hasMetrics && this.console.log(JSON.stringify(emfOutput));
@@ -809,9 +810,9 @@ class Metrics extends Utility implements MetricsInterface {
    * - `POWERTOOLS_FUNCTION_NAME` environment variable
    * - {@link Metrics.captureColdStartMetric | `captureColdStartMetric('myFunctionName')`} method
    */
-  /* v8 ignore start */ public setFunctionName(name: string): void {
+  /* v8 ignore next -- @preserve */ public setFunctionName(name: string): void {
     this.functionName = name;
-  } /* v8 ignore end */
+  }
 
   /**
    * Set the flag to throw an error if no metrics are emitted.
@@ -866,9 +867,9 @@ class Metrics extends Utility implements MetricsInterface {
   /**
    * @deprecated Use {@link Metrics.setThrowOnEmptyMetrics | `setThrowOnEmptyMetrics()`} instead.
    */
-  /* v8 ignore start */ public throwOnEmptyMetrics(): void {
+  /* v8 ignore next -- @preserve */ public throwOnEmptyMetrics(): void {
     this.shouldThrowOnEmptyMetrics = true;
-  } /* v8 ignore stop */
+  }
 
   /**
    * Get the custom config service if it exists.

packages/parameters/src/appconfig/AppConfigProvider.ts

@@ -259,12 +259,9 @@ class AppConfigProvider extends BaseProvider {
   /**
    * Retrieving multiple configurations is not supported by AWS AppConfig.
    */
-  /* v8 ignore start */ public async getMultiple(
-    path: string,
-    _options?: unknown
-  ): Promise<void> {
+  public async getMultiple(path: string, _options?: unknown): Promise<void> {
     await super.getMultiple(path);
-  } /* v8 ignore stop */
+  }
 
   /**
    * Retrieve a configuration from AWS AppConfig.

packages/parameters/src/base/BaseProvider.ts

@@ -46,6 +46,7 @@ abstract class BaseProvider implements BaseProviderInterface {
     awsSdkV3ClientPrototype,
   }: BaseProviderConstructorOptions) {
     this.store = new Map();
+    /* v8 ignore else -- @preserve */
     if (awsSdkV3Client) {
       if (!isSdkClient(awsSdkV3Client) && awsSdkV3ClientPrototype) {
         console.warn(
@@ -164,6 +165,7 @@ abstract class BaseProvider implements BaseProviderInterface {
             entryKey
           );
         } catch (error) {
+          /* v8 ignore else -- @preserve */
           if (configs.throwOnTransformError) {
             if (error instanceof TransformParameterError) {
               throw error;

packages/parameters/src/base/DefaultProviders.ts

@@ -10,6 +10,7 @@ const DEFAULT_PROVIDERS: Record<string, BaseProviderInterface> = {};
  */
 const clearCaches = (): void => {
   for (const provider of Object.values(DEFAULT_PROVIDERS)) {
+    /* v8 ignore else -- @preserve */
     if (provider.clearCache) {
       provider.clearCache();
     }