suggestion change

lib/fetch/dataURL.js

@@ -26,7 +26,7 @@ function dataURLProcessor (dataURL) {
   let input = URLSerializer(dataURL, true)
 
   // 3. Remove the leading "data:" string from input.
-  input = input.substring(5)
+  input = input.slice(5)
 
   // 4. Let position point at the start of input.
   const position = { position: 0 }
@@ -59,7 +59,7 @@ function dataURLProcessor (dataURL) {
   position.position++
 
   // 9. Let encodedBody be the remainder of input.
-  const encodedBody = input.substring(mimeTypeLength + 1)
+  const encodedBody = input.slice(mimeTypeLength + 1)
 
   // 10. Let body be the percent-decoding of encodedBody.
   let body = stringPercentDecode(encodedBody)
@@ -165,11 +165,11 @@ function collectASequenceOfCodePointsFast (char, input, position) {
 
   if (idx === -1) {
     position.position = input.length
-    return input.substring(start)
+    return input.slice(start)
   }
 
   position.position = idx
-  return input.substring(start, position.position)
+  return input.slice(start, position.position)
 }
 
 // https://url.spec.whatwg.org/#string-percent-decode
@@ -515,7 +515,7 @@ function collectAnHTTPQuotedString (input, position, extractValue) {
 
   // 7. Return the code points from positionStart to position,
   // inclusive, within input.
-  return input.substring(positionStart, position.position)
+  return input.slice(positionStart, position.position)
 }
 
 /**