fix: readable.setEncoding

Fixes: #1125 (comment)

lib/api/readable.js

@@ -102,12 +102,12 @@ module.exports = class BodyReadable extends Readable {
 
   // https://fetch.spec.whatwg.org/#dom-body-text
   async text () {
-    return consume(this, 'text')
+    return toUSVString(await consume(this, 'string'))
   }
 
   // https://fetch.spec.whatwg.org/#dom-body-json
   async json () {
-    return consume(this, 'json')
+    return JSON.parse(await consume(this, 'string'))
   }
 
   // https://fetch.spec.whatwg.org/#dom-body-blob
@@ -231,10 +231,12 @@ function consumeEnd (consume) {
   const { type, body, resolve, stream, length } = consume
 
   try {
-    if (type === 'text') {
-      resolve(toUSVString(Buffer.concat(body)))
-    } else if (type === 'json') {
-      resolve(JSON.parse(Buffer.concat(body)))
+    if (type === 'string') {
+      if (stream.readableEncoding) {
+        resolve(body.join(''))
+      } else {
+        resolve(Buffer.concat(body).toString())
+      }
     } else if (type === 'arrayBuffer') {
       const dst = new Uint8Array(length)