Raise TypeScript baseline to 5.9 and adopt generic Uint8Array types

harmony7 · harmony7 · commit 429303bb1089 · 2025-10-10T16:37:58.000+09:00
diff --git a/package-lock.json b/package-lock.json
diff --git a/package.json b/package.json
@@ -52,7 +52,7 @@
     "remark-parse": "^11.0.0",
     "remark-stringify": "^11.0.0",
     "tsd": "^0.31.1",
-    "typescript": "^5.5",
+    "typescript": "^5.9.0",
     "unified": "^11.0.5"
   },
   "dependencies": {
@@ -64,5 +64,13 @@
     "esbuild": "^0.25.0",
     "magic-string": "^0.30.12",
     "regexpu-core": "^6.1.1"
+  },
+  "peerDependencies": {
+    "typescript": "^5.9.0"
+  },
+  "peerDependenciesMeta": {
+    "typescript": {
+      "optional": true
+    }
   }
 }
diff --git a/types/cache-override.d.ts b/types/cache-override.d.ts
@@ -37,8 +37,8 @@ declare module 'fastly:cache-override' {
      * to return the new body.
      */
     bodyTransformFn?: (
-      body: Uint8Array,
-    ) => Uint8Array | PromiseLike<Uint8Array>;
+      body: Uint8Array<ArrayBuffer>,
+    ) => Uint8Array<ArrayBuffer> | PromiseLike<Uint8Array<ArrayBuffer>>;
   }
   /**
    * The cache override mode for a request
diff --git a/types/experimental.d.ts b/types/experimental.d.ts
@@ -46,7 +46,7 @@ declare module 'fastly:experimental' {
    * **Note**: Can only be used during build-time initialization, not when processing requests.
    * @experimental
    */
-  export function includeBytes(path: string): Uint8Array;
+  export function includeBytes(path: string): Uint8Array<ArrayBuffer>;
 
   /**
    * Whether or not to allow Dynamic Backends.
diff --git a/types/globals.d.ts b/types/globals.d.ts
@@ -843,7 +843,7 @@ declare class TextEncoder {
    * UTF-8 encodes the `input` string and returns a `Uint8Array` containing the encoded bytes.
    * @param [input='an empty string'] The text to encode.
    */
-  encode(input?: string): Uint8Array;
+  encode(input?: string): Uint8Array<ArrayBuffer>;
   // /**
   //  * UTF-8 encodes the `src` string to the `dest` Uint8Array and returns an object
   //  * containing the read Unicode code units and written UTF-8 bytes.
@@ -998,7 +998,7 @@ declare interface Fastly {
    * @hidden
    * @experimental
    */
-  includeBytes(path: string): Uint8Array;
+  includeBytes(path: string): Uint8Array<ArrayBuffer>;
 }
 
 /**
@@ -1055,15 +1055,15 @@ declare class CompressionStream {
    * console.log(stream.readable instanceof ReadableStream); // true
    * ```
    */
-  readonly readable: ReadableStream<Uint8Array>;
+  readonly readable: ReadableStream<Uint8Array<ArrayBuffer>>;
   /**
    * @example
    * ```js
    * let stream = new CompressionStream("gzip");
    * console.log(stream.writable instanceof WritableStream); // true
    * ```
    */
-  readonly writable: WritableStream<Uint8Array>;
+  readonly writable: WritableStream<Uint8Array<ArrayBuffer>>;
 }
 
 /**
@@ -1110,15 +1110,15 @@ declare class DecompressionStream {
    * console.log(stream.readable instanceof ReadableStream); // true
    * ```
    */
-  readonly readable: ReadableStream<Uint8Array>;
+  readonly readable: ReadableStream<Uint8Array<ArrayBuffer>>;
   /**
    * @example
    * ```js
    * let stream = new DecompressionStream("gzip");
    * console.log(stream.writable instanceof WritableStream); // true
    * ```
    */
-  readonly writable: WritableStream<Uint8Array>;
+  readonly writable: WritableStream<Uint8Array<ArrayBuffer>>;
 }
 
 // Note: the contents below here are, partially modified, copies of content from TypeScript's
@@ -1175,7 +1175,7 @@ interface Blob {
   /** [MDN Reference](https://developer.mozilla.org/docs/Web/API/Blob/slice) */
   slice(start?: number, end?: number, contentType?: string): Blob;
   /** [MDN Reference](https://developer.mozilla.org/docs/Web/API/Blob/stream) */
-  stream(): ReadableStream<Uint8Array>;
+  stream(): ReadableStream<Uint8Array<ArrayBuffer>>;
   /** [MDN Reference](https://developer.mozilla.org/docs/Web/API/Blob/text) */
   text(): Promise<string>;
 }
@@ -1265,7 +1265,7 @@ declare type XMLHttpRequestBodyInit =
  * @group Fetch API
  */
 declare interface Body {
-  readonly body: ReadableStream<Uint8Array> | null;
+  readonly body: ReadableStream<Uint8Array<ArrayBuffer>> | null;
   readonly bodyUsed: boolean;
   arrayBuffer(): Promise<ArrayBuffer>;
   blob(): Promise<Blob>;
diff --git a/types/secret-store.d.ts b/types/secret-store.d.ts
@@ -39,6 +39,6 @@ declare module 'fastly:secret-store' {
      *       always avoid using this method when possible, instead passing
      *       the secret directly.
      */
-    rawBytes(): Uint8Array;
+    rawBytes(): Uint8Array<ArrayBuffer>;
   }
 }

Original file line number	Diff line number	Diff line change
`@@ -39,6 +39,6 @@ declare module 'fastly:secret-store' {`
`39`	`39`	`* always avoid using this method when possible, instead passing`
`40`	`40`	`* the secret directly.`
`41`	`41`	`*/`
`42`		`- rawBytes(): Uint8Array;`
	`42`	`+ rawBytes(): Uint8Array<ArrayBuffer>;`
`43`	`43`	`}`
`44`	`44`	`}`