4 files changed, 19 insertions, 22 deletions

diff --git a/cli/js/web/blob.ts b/cli/js/web/blob.ts
index 896337b10..1309ddff0 100644
--- a/cli/js/web/blob.ts
+++ b/cli/js/web/blob.ts
@@ -1,6 +1,5 @@
 // Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
 import * as domTypes from "./dom_types.ts";
-import { hasOwnProperty } from "../util.ts";
 import { TextEncoder } from "./text_encoding.ts";
 import { build } from "../build.ts";
 
@@ -144,34 +143,29 @@ export class DenoBlob implements domTypes.Blob {
       return;
     }
 
-    options = options || {};
-    // Set ending property's default value to "transparent".
-    if (!hasOwnProperty(options, "ending")) {
-      options.ending = "transparent";
-    }
-
-    if (options.type && !containsOnlyASCII(options.type)) {
+    const { ending = "transparent", type = "" } = options ?? {};
+    if (!containsOnlyASCII(type)) {
       const errMsg = "The 'type' property must consist of ASCII characters.";
       throw new SyntaxError(errMsg);
     }
 
-    const bytes = processBlobParts(blobParts!, options);
+    const bytes = processBlobParts(blobParts!, { ending, type });
     // Normalize options.type.
-    let type = options.type ? options.type : "";
+    let normalizedType = type;
     if (type.length) {
       for (let i = 0; i < type.length; ++i) {
         const char = type[i];
         if (char < "\u0020" || char > "\u007E") {
-          type = "";
+          normalizedType = "";
           break;
         }
       }
-      type = type.toLowerCase();
+      normalizedType = type.toLowerCase();
     }
     // Set Blob object's properties.
     this[bytesSymbol] = bytes;
     this.size = bytes.byteLength;
-    this.type = type;
+    this.type = normalizedType;
 
     // Register bytes for internal private use.
     blobBytesWeakMap.set(this, bytes);
diff --git a/cli/js/web/dom_file.ts b/cli/js/web/dom_file.ts
index 2b9dbff24..cf2a40398 100644
--- a/cli/js/web/dom_file.ts
+++ b/cli/js/web/dom_file.ts
@@ -11,14 +11,14 @@ export class DomFileImpl extends blob.DenoBlob implements domTypes.DomFile {
     fileName: string,
     options?: domTypes.FilePropertyBag
   ) {
-    options = options || {};
-    super(fileBits, options);
+    const { lastModified = Date.now(), ...blobPropertyBag } = options ?? {};
+    super(fileBits, blobPropertyBag);
 
     // 4.1.2.1 Replace any "/" character (U+002F SOLIDUS)
     // with a ":" (U + 003A COLON)
     this.name = String(fileName).replace(/\u002F/g, "\u003A");
     // 4.1.3.3 If lastModified is not provided, set lastModified to the current
     // date and time represented in number of milliseconds since the Unix Epoch.
-    this.lastModified = options.lastModified || Date.now();
+    this.lastModified = lastModified;
   }
 }
diff --git a/cli/js/web/dom_types.ts b/cli/js/web/dom_types.ts
index cdd681615..23347ce66 100644
--- a/cli/js/web/dom_types.ts
+++ b/cli/js/web/dom_types.ts
@@ -258,12 +258,12 @@ interface ProgressEvent extends Event {
 }
 
 export interface EventListenerOptions {
-  capture: boolean;
+  capture?: boolean;
 }
 
 export interface AddEventListenerOptions extends EventListenerOptions {
-  once: boolean;
-  passive: boolean;
+  once?: boolean;
+  passive?: boolean;
 }
 
 export interface AbortSignal extends EventTarget {
diff --git a/cli/js/web/text_encoding.ts b/cli/js/web/text_encoding.ts
index 0709e7123..928cbe7e1 100644
--- a/cli/js/web/text_encoding.ts
+++ b/cli/js/web/text_encoding.ts
@@ -154,11 +154,14 @@ class SingleByteDecoder implements Decoder {
   private _index: number[];
   private _fatal: boolean;
 
-  constructor(index: number[], options: DecoderOptions) {
-    if (options.ignoreBOM) {
+  constructor(
+    index: number[],
+    { ignoreBOM = false, fatal = false }: DecoderOptions = {}
+  ) {
+    if (ignoreBOM) {
       throw new TypeError("Ignoring the BOM is available only with utf-8.");
     }
-    this._fatal = options.fatal || false;
+    this._fatal = fatal;
     this._index = index;
   }
   handler(stream: Stream, byte: number): number {