buffer: make Blob's constructor more spec-compliant

PR-URL: #37361
Fixes: #37352
Fixes: #37356
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: targos

lib/internal/blob.js

@@ -48,7 +48,6 @@ const {
 
 const {
   validateObject,
-  validateString,
   isUint32,
 } = require('internal/validators');
 
@@ -74,22 +73,10 @@ function getSource(source, encoding) {
   if (isBlob(source))
     return [source.size, source[kHandle]];
 
-  if (typeof source === 'string') {
-    source = lazyBuffer().from(source, encoding);
-  } else if (isAnyArrayBuffer(source)) {
+  if (isAnyArrayBuffer(source)) {
     source = new Uint8Array(source);
   } else if (!isArrayBufferView(source)) {
-    throw new ERR_INVALID_ARG_TYPE(
-      'source',
-      [
-        'string',
-        'ArrayBuffer',
-        'SharedArrayBuffer',
-        'Buffer',
-        'TypedArray',
-        'DataView'
-      ],
-      source);
+    source = lazyBuffer().from(`${source}`, encoding);
   }
 
   // We copy into a new Uint8Array because the underlying
@@ -110,19 +97,16 @@ class InternalBlob extends JSTransferable {
 }
 
 class Blob extends JSTransferable {
-  constructor(sources = [], options) {
+  constructor(sources = [], options = {}) {
     emitExperimentalWarning('buffer.Blob');
     if (sources === null ||
         typeof sources[SymbolIterator] !== 'function' ||
         typeof sources === 'string') {
       throw new ERR_INVALID_ARG_TYPE('sources', 'Iterable', sources);
     }
-    if (options !== undefined)
-      validateObject(options, 'options');
-    const {
-      encoding = 'utf8',
-      type = '',
-    } = { ...options };
+    validateObject(options, 'options');
+    const { encoding = 'utf8' } = options;
+    let { type = '' } = options;
 
     let length = 0;
     const sources_ = ArrayFrom(sources, (source) => {
@@ -131,16 +115,14 @@ class Blob extends JSTransferable {
       return src;
     });
 
-    // This is a MIME media type but we're not actively checking the syntax.
-    // But, to be fair, neither does Chrome.
-    validateString(type, 'options.type');
-
     if (!isUint32(length))
       throw new ERR_BUFFER_TOO_LARGE(0xFFFFFFFF);
 
     super();
     this[kHandle] = createBlob(sources_, length);
     this[kLength] = length;
+
+    type = `${type}`;
     this[kType] = RegExpPrototypeTest(disallowedTypeCharacters, type) ?
       '' : StringPrototypeToLowerCase(type);
   }

test/parallel/test-blob.js

@@ -22,10 +22,6 @@ assert.throws(() => new Blob({}), {
   code: 'ERR_INVALID_ARG_TYPE'
 });
 
-assert.throws(() => new Blob(['test', 1]), {
-  code: 'ERR_INVALID_ARG_TYPE'
-});
-
 {
   const b = new Blob([]);
   assert(b);
@@ -43,15 +39,9 @@ assert.throws(() => new Blob(['test', 1]), {
 }
 
 {
-  assert.throws(() => new Blob([], { type: 1 }), {
-    code: 'ERR_INVALID_ARG_TYPE'
-  });
-  assert.throws(() => new Blob([], { type: false }), {
-    code: 'ERR_INVALID_ARG_TYPE'
-  });
-  assert.throws(() => new Blob([], { type: {} }), {
-    code: 'ERR_INVALID_ARG_TYPE'
-  });
+  assert.strictEqual(new Blob([], { type: 1 }).type, '1');
+  assert.strictEqual(new Blob([], { type: false }).type, 'false');
+  assert.strictEqual(new Blob([], { type: {} }).type, '[object object]');
 }
 
 {
@@ -193,3 +183,10 @@ assert.throws(() => new Blob(['test', 1]), {
     writable: false
   });
 }
+
+{
+  const b = new Blob(['test', 42]);
+  b.text().then(common.mustCall((text) => {
+    assert.strictEqual(text, 'test42');
+  }));
+}