DevTools: NetworkPanel: use optimistic JSON parser for response preview.

Source/devtools/front_end/network/RequestJSONView.js

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 24 matching lines @@
  * @param {!WebInspector.ParsedJSON} parsedJSON
  */
 WebInspector.RequestJSONView = function(request, parsedJSON)
 {
     WebInspector.RequestView.call(this, request);
     this._parsedJSON = parsedJSON;
     this.element.classList.add("json");
 }
 
 /**
+ * @return {*}
+ */
+WebInspector.RequestJSONView.buildJSON = function(text)

[vsevik, 2014/10/16 06:51:35]

buildObjectFromJSON

[eustas, 2014/10/16 14:14:56]

Done.

+{
+    // Based on https://code.google.com/p/json-sans-eval/
+
+    var jsonToken = new RegExp('(?:false|true|null|[,\\{\\}\\[\\]]|(?:-?\\b(?:0|[1-9][0-9]*)(?:\\.[0-9]+)?(?:[eE][+-]?[0-9]+)?\\b)|(?:\"(?:[^\\0-\\x08\\x0a-\\x1f\"\\\\]|\\\\(?:[\"/\\\\bfnrt]|u[0-9A-Fa-f]{4}))*\"))', 'g');
+    var escapeSequence = new RegExp('\\\\(?:([^u])|u(.{4}))', 'g');
+    var escapes = {'"': '"', '/': '/', '\\': '\\', 'b': '\b', 'f': '\f', 'n': '\n', 'r': '\r', 't': '\t'};
+
+    function unescapeOne(_, ch, hex)
+    {
+        return ch ? escapes[ch] : String.fromCharCode(parseInt(hex, 16));
+    }
+
+    var emptyString = new String('');
+    var slash = '\\';
+    var toks = text.match(jsonToken);
+    var result = [];
+    var tok = toks[0];
+    var topLevelPrimitive = false;
+    if ('{' === tok)
+        result = {};
+    else if ('[' !== tok)
+        topLevelPrimitive = true;
+
+    var key;
+    var noEntry = true;
+    var stack = [result];
+    for (var i = 1 - topLevelPrimitive, n = toks.length; i < n; ++i) {
+        tok = toks[i];
+        var cont;
+        var wasNoEntry = noEntry;
+        noEntry = false;
+        switch (tok.charCodeAt(0)) {
+        default: // sign or digit
+            cont = stack[0];
+            cont[key || cont.length] = +(tok);
+            key = void 0;
+            break;
+        case 0x22: // "
+            tok = tok.substring(1, tok.length - 1);
+            if (tok.indexOf(slash) !== -1)
+                tok = tok.replace(escapeSequence, unescapeOne);
+            cont = stack[0];
+            if (!key) {
+                if (cont instanceof Array) {
+                  key = cont.length;
+                } else {
+                    key = tok || emptyString;
+                    break;
+                }
+            }
+            cont[key] = tok;
+            key = void 0;
+            break;
+        case 0x2C: // "
+            cont = stack[0];
+            if (wasNoEntry && (cont instanceof Array))
+                cont[key || cont.length] = undefined;
+            noEntry = true;
+            break;
+        case 0x5b: // [
+            cont = stack[0];
+            stack.unshift(cont[key || cont.length] = []);
+            key = void 0;
+            noEntry = true;
+            break;
+        case 0x5d: // ]
+            stack.shift();
+            break;
+        case 0x66: // f
+            cont = stack[0];
+            cont[key || cont.length] = false;
+            key = void 0;
+            break;
+        case 0x6e: // n
+            cont = stack[0];
+            cont[key || cont.length] = null;
+            key = void 0;
+            break;
+        case 0x74: // t
+            cont = stack[0];
+            cont[key || cont.length] = true;
+            key = void 0;
+            break;
+        case 0x7b: // {
+            cont = stack[0];
+            stack.unshift(cont[key || cont.length] = {});
+            key = void 0;
+            break;
+        case 0x7d: // }
+            stack.shift();
+            break;
+        }
+    }
+    if (topLevelPrimitive) {
+        if (stack.length !== 1)
+            throw new Error();
+        result = result[0];
+    } else {
+        if (stack.length)
+            throw new Error();
+    }
+    return result;
+}
+
+/**
  * @param {string} text
  * @return {?WebInspector.ParsedJSON}
  */
 WebInspector.RequestJSONView.parseJSON = function(text)
 {
     var prefix = "";
 
     // Trim while(1), for(;;), weird numbers, etc. We need JSON start.
     var start = /[{[]/.exec(text);
     if (start && start.index) {
         prefix = text.substring(0, start.index);
         text = text.substring(start.index);
     }
 
     try {
-        return new WebInspector.ParsedJSON(JSON.parse(text), prefix, "");
+        return new WebInspector.ParsedJSON(WebInspector.RequestJSONView.buildJSON(text), prefix, "");

[vsevik, 2014/10/16 06:51:34]

We should make sure this returns correct suffix

[eustas, 2014/10/16 14:14:56]

Done.

     } catch (e) {
         return null;
     }
 }
 
 /**
  * @param {string} text
  * @return {?WebInspector.ParsedJSON}
  */
 WebInspector.RequestJSONView.parseJSONP = function(text)

[vsevik, 2014/10/16 06:51:34]

So this one is not needed anymore?

[eustas, 2014/10/16 14:14:56]

Yup. Removed.

 {
     // Taking everything between first and last parentheses
     var start = text.indexOf("(");
     var end = text.lastIndexOf(")");
     if (start == -1 || end == -1 || end < start)
         return null;
 
     var prefix = text.substring(0, start + 1);
     var suffix = text.substring(end);
     text = text.substring(start + 1, end);
 
     try {
-        return new WebInspector.ParsedJSON(JSON.parse(text), prefix, suffix);
+        return new WebInspector.ParsedJSON(WebInspector.RequestJSONView.buildJSON(text), prefix, suffix);
     } catch (e) {
         return null;
     }
 }
 
 WebInspector.RequestJSONView.prototype = {
     wasShown: function()
     {
         this._initialize();
     },
@@ skipping 17 matching lines @@
 
 /**
  * @constructor
  */
 WebInspector.ParsedJSON = function(data, prefix, suffix)
 {
     this.data = data;
     this.prefix = prefix;
     this.suffix = suffix;
 }