update eslint to v9

BUILD.bazel

@@ -1,3 +1,4 @@
+load("@aspect_rules_js//js:defs.bzl", "js_library")
 load("@aspect_rules_js//npm:defs.bzl", "npm_link_package")
 load("@bazel_skylib//lib:selects.bzl", "selects")
 load("@bazel_skylib//rules:common_settings.bzl", "bool_flag")
@@ -89,3 +90,10 @@ selects.config_setting_group(
         ":not_dbg_build",
     ],
 )
+
+# prettier
+js_library(
+    name = "prettierrc",
+    srcs = [".prettierrc.json"],
+    visibility = ["//visibility:public"],
+)

build/wd_ts_bundle.bzl

@@ -91,7 +91,8 @@ def wd_ts_bundle_capnp(
             data = srcs + [
                 eslintrc_json,
                 tsconfig_json,
-                "//:node_modules/@typescript-eslint/eslint-plugin",
+                "//tools:base-eslint",
+                "//:prettierrc",
             ],
             tags = ["lint"],
             target_compatible_with = select({

package.json

@@ -7,24 +7,23 @@
   },
   "dependencies": {
     "capnp-ts": "^0.7.0",
-    "prettier": "^3.2.5",
+    "prettier": "^3.3.3",
     "typescript": "5.5.4"
   },
   "devDependencies": {
     "@bazel/bazelisk": "~1.19.0",
+    "@eslint/js": "^9.9.0",
     "@types/debug": "^4.1.10",
+    "@types/eslint__js": "^8.42.3",
     "@types/node": "^20.14.8",
-    "@types/prettier": "^2.7.1",
-    "@typescript-eslint/eslint-plugin": "^7.3.1",
-    "@typescript-eslint/parser": "^7.3.1",
     "capnpc-ts": "^0.7.0",
     "chrome-remote-interface": "^0.33.2",
     "esbuild": "^0.15.18",
-    "eslint": "^8.57.0",
-    "eslint-config-prettier": "^9.1.0",
+    "eslint": "^9.9.0",
     "eslint-plugin-import": "^2.29.1",
-    "eslint-plugin-prettier": "^5.1.3",
-    "expect-type": "^0.18.0"
+    "eslint-plugin-prettier": "^5.2.1",
+    "expect-type": "^0.18.0",
+    "typescript-eslint": "^8.2.0"
   },
   "pnpm": {
     "overrides": {

src/cloudflare/BUILD.bazel

@@ -2,7 +2,7 @@ load("@workerd//:build/wd_ts_bundle.bzl", "wd_ts_bundle")
 
 wd_ts_bundle(
     name = "cloudflare",
-    eslintrc_json = ".eslintrc.json",
+    eslintrc_json = "eslint.config.mjs",
     import_name = "cloudflare",
     internal_modules = glob(
         [

src/cloudflare/eslint.config.mjs

@@ -0,0 +1,4 @@
+import { baseConfig } from '../../tools/base.eslint.config.mjs';
+
+// eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+export default [...baseConfig({ tsconfigRootDir: import.meta.dirname })];

src/cloudflare/internal/ai-api.ts

@@ -79,7 +79,7 @@ export class Ai {
       extraHeaders,
       sessionOptions,
       ...object
-    }): object => object)(this.options || {});
+    }): object => object)(this.options);
 
     const body = JSON.stringify({
       inputs,
@@ -90,8 +90,8 @@ export class Ai {
       method: 'POST',
       body: body,
       headers: {
-        ...(this.options?.sessionOptions?.extraHeaders || {}),
-        ...(this.options?.extraHeaders || {}),
+        ...(this.options.sessionOptions?.extraHeaders || {}),
+        ...(this.options.extraHeaders || {}),
         'content-type': 'application/json',
         'cf-consn-sdk-version': '2.0.0',
         'cf-consn-model-id': `${this.options.prefix ? `${this.options.prefix}:` : ''}${model}`,

src/cloudflare/internal/d1-api.ts

@@ -108,11 +108,7 @@ class D1DatabaseWithSessionAPI extends D1Database {
     constraintOrToken: D1SessionCommitTokenOrConstraint | null | undefined
   ): D1DatabaseSession {
     constraintOrToken = constraintOrToken?.trim();
-    if (
-      constraintOrToken === null ||
-      constraintOrToken === undefined ||
-      constraintOrToken === ''
-    ) {
+    if (constraintOrToken == null || constraintOrToken === '') {
       constraintOrToken = D1_SESSION_CONSTRAINT_FIRST_UNCONSTRAINED;
     }
     return new D1DatabaseSession(this.fetcher, constraintOrToken);
@@ -181,6 +177,7 @@ class D1DatabaseSession {
     switch (this.commitTokenOrConstraint) {
       // First to any replica, and then anywhere that satisfies the commit token.
       case D1_SESSION_CONSTRAINT_FIRST_UNCONSTRAINED:
+        return null;
       // First to primary, and then anywhere that satisfies the commit token.
       case D1_SESSION_CONSTRAINT_FIRST_PRIMARY:
         return null;
@@ -449,7 +446,7 @@ class D1PreparedStatement {
 
     const firstResult = results[0]!;
     if (colName !== undefined) {
-      if (hasResults && firstResult[colName] === undefined) {
+      if (firstResult[colName] === undefined) {
         throw new Error(`D1_COLUMN_NOTFOUND: Column not found (${colName})`, {
           cause: new Error('Column not found'),
         });
@@ -460,6 +457,7 @@ class D1PreparedStatement {
     }
   }
 
+  /* eslint-disable-next-line @typescript-eslint/no-unnecessary-type-parameters */
   public async run<T = Record<string, unknown>>(): Promise<D1Response> {
     return firstIfArray(
       await this.dbSession._sendOrThrow<T>(
@@ -554,12 +552,12 @@ function mapD1Result<T>(result: D1UpstreamResponse<T>): D1UpstreamResponse<T> {
   return result.error
     ? {
         success: false,
-        meta: result.meta || {},
+        meta: result.meta,
         error: result.error,
       }
     : {
         success: true,
-        meta: result.meta || {},
+        meta: result.meta,
         ...('results' in result ? { results: result.results } : {}),
       };
 }

src/cloudflare/internal/images-api.ts

@@ -63,7 +63,7 @@ class ImageTransformerImpl implements ImageTransformer {
     this.consumed = false;
   }
 
-  public transform(transform: Transform): ImageTransformerImpl {
+  public transform(transform: Transform): this {
     this.transforms.push(transform);
     return this;
   }

src/cloudflare/internal/pipeline-transform.ts

@@ -13,7 +13,7 @@ async function* readLines(
 
   // @ts-expect-error must have a '[Symbol.asyncIterator]()' method
   for await (const chunk of stream) {
-    const full = partial + chunk;
+    const full = partial + (chunk as string);
     for (const char of full) {
       if (char === '\n') {
         yield full.substring(start, end);
@@ -68,13 +68,15 @@ export class PipelineTransformImpl extends entrypoints.WorkerEntrypoint {
 
   // called by the dispatcher which then calls the subclass methods
   // @ts-expect-error thinks ping is never used
-  private async _ping(): Promise<void> {
+  private _ping(): Promise<void> {
     // making sure the function was overriden by an implementing subclass
     if (this.transformJson !== PipelineTransformImpl.prototype.transformJson) {
-      return await Promise.resolve(); // eslint
+      return Promise.resolve();
     } else {
-      throw new Error(
-        'the transformJson method must be overridden by the PipelineTransform subclass'
+      return Promise.reject(
+        new Error(
+          'the transformJson method must be overridden by the PipelineTransform subclass'
+        )
       );
     }
   }
@@ -92,16 +94,18 @@ export class PipelineTransformImpl extends entrypoints.WorkerEntrypoint {
     this.#initalized = true;
 
     switch (this.#batch.format) {
-      case Format.JSON_STREAM:
+      case Format.JSON_STREAM: {
         const data = await this.#readJsonStream();
         const transformed = await this.transformJson(data);
         return this.#sendJson(transformed);
+      }
       default:
         throw new Error('unsupported batch format');
     }
   }
 
   async #readJsonStream(): Promise<object[]> {
+    // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
     if (this.#batch!.format !== Format.JSON_STREAM) {
       throw new Error(`expected JSON_STREAM not ${this.#batch!.format}`);
     }

src/cloudflare/internal/vectorize-api.ts

@@ -57,6 +57,7 @@ class VectorizeIndexImpl implements Vectorize {
 
         if (typeof options.returnMetadata === 'boolean') {
           // Allow boolean returnMetadata for backward compatibility. true converts to 'all' and false converts to 'none'
+          // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
           options.returnMetadata = options.returnMetadata ? 'all' : 'none';
         }
       }
@@ -226,7 +227,9 @@ class VectorizeIndexImpl implements Vectorize {
             cause: new Error(errResponse.error),
           }
         );
-      } catch {}
+      } catch {
+        // do nothing
+      }
 
       if (err) {
         throw err;

src/node/BUILD.bazel

@@ -2,7 +2,7 @@ load("@workerd//:build/wd_ts_bundle.bzl", "wd_ts_bundle")
 
 wd_ts_bundle(
     name = "node",
-    eslintrc_json = ".eslintrc.json",
+    eslintrc_json = "eslint.config.mjs",
     import_name = "node",
     internal_modules = glob([
         "internal/*.ts",

src/node/eslint.config.mjs

@@ -0,0 +1,3 @@
+import { baseConfig } from '../../tools/base.eslint.config.mjs';
+
+export default [...baseConfig({ tsconfigRootDir: import.meta.dirname })];

src/node/internal/internal_zlib_base.ts

@@ -113,6 +113,7 @@ function processCallback(this: ZlibHandleType): void {
     assert.strictEqual(have, 0, 'have should not go down');
   }
 
+  /* eslint-disable-next-line @typescript-eslint/no-unnecessary-condition */
   if (self.destroyed) {
     this.cb();
     return;
@@ -254,11 +255,12 @@ function processChunkSync(
   let offset = self._outOffset;
   const chunkSize = self._chunkSize;
 
-  let error;
+  let error: Error | undefined;
   self.on('error', function onError(er) {
     error = er;
   });
 
+  /* eslint-disable-next-line @typescript-eslint/no-unnecessary-condition */
   while (true) {
     ok(handle, 'Handle should have been defined');
     handle.writeSync(
@@ -371,6 +373,7 @@ export class ZlibBase extends Transform {
       flushBoundIdx = FLUSH_BOUND_IDX_BROTLI;
     }
 
+    /* eslint-disable-next-line @typescript-eslint/no-unnecessary-condition */
     if (opts) {
       if (opts.chunkSize != null) {
         chunkSize = opts.chunkSize;
@@ -430,7 +433,7 @@ export class ZlibBase extends Transform {
     this._defaultFlushFlag = flush;
     this._finishFlushFlag = finishFlush;
     this._defaultFullFlushFlag = fullFlush;
-    this._info = Boolean(opts?.info);
+    this._info = Boolean(opts.info);
     this._maxOutputLength = maxOutputLength;
   }
 
@@ -684,7 +687,7 @@ export class Zlib extends ZlibBase {
   #paramsAfterFlushCallback(
     level: number,
     strategy: number,
-    callback: () => void
+    callback?: () => void
   ): void {
     ok(this._handle, 'zlib binding closed');
     this._handle.params(level, strategy);

src/node/internal/streams_transform.d.ts

@@ -287,6 +287,8 @@ export class Duplex extends Readable implements Writable {
   readonly writableLength: number;
   readonly writableObjectMode: boolean;
   readonly writableCorked: number;
+  readonly destroyed: boolean;
+
   allowHalfOpen: boolean;
   constructor(opts?: DuplexOptions);
   _write(
@@ -465,6 +467,7 @@ interface TransformOptions extends DuplexOptions {
 type TransformCallback = (error?: Error | null, data?: any) => void;
 
 export class Transform extends Duplex {
+  readonly destroyed: boolean;
   constructor(opts?: TransformOptions);
   _transform(
     chunk: any,