JSON.parse errors made user-friendly part 2

Part of the improve error messages initiative.

Based on a resource of JSON.parse() errors found at
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/JSON_bad_parse

added support for:
- 'Bad control character in string literal'
- 'Bad Unicode escape'

Previously JSON.parse('"a\bz"') would output:
SyntaxError: Unexpected token  in JSON at position 2
Now the output is:
SyntaxError: Bad control character in string literal in
JSON at position 2

Previously JSON.parse("[\"\\t\\u") would output:
SyntaxError: Unexpected end of JSON input
Now the output is:
SyntaxError: Bad Unicode escape in JSON at position 6

Bug: v8:6551
Change-Id: I3ba5450c41b8a388643a15bc58e4e3fc75855d13
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3652254Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Issack John <issackjohn@microsoft.com>
Cr-Commit-Position: refs/heads/main@{#80642}

src/common/message-template.h

@@ -504,6 +504,9 @@ namespace internal {
     "%")                                                                       \
   T(JsonParseBadEscapedCharacter,                                              \
     "Bad escaped character in JSON at position %")                             \
+  T(JsonParseBadControlCharacter,                                              \
+    "Bad control character in string literal in JSON at position %")           \
+  T(JsonParseBadUnicodeEscape, "Bad Unicode escape in JSON at position %")     \
   T(JsonParseNoNumberAfterMinusSign,                                           \
     "No number after minus sign in JSON at position %")                        \
   T(JsonParseShortString, "\"%\" is not valid JSON")                           \

src/json/json-parser.cc

@@ -1270,7 +1270,8 @@ JsonString JsonParser<Char>::ScanJsonString(bool needs_internalization) {
           base::uc32 value = ScanUnicodeCharacter();
           if (value == kInvalidUnicodeCharacter) {
             AllowGarbageCollection allow_before_exception;
-            ReportUnexpectedCharacter(CurrentCharacter());
+            ReportUnexpectedToken(JsonToken::ILLEGAL,
+                                  MessageTemplate::kJsonParseBadUnicodeEscape);
             return JsonString();
           }
           bits |= value;
@@ -1294,7 +1295,8 @@ JsonString JsonParser<Char>::ScanJsonString(bool needs_internalization) {
 
     DCHECK_LT(*cursor_, 0x20);
     AllowGarbageCollection allow_before_exception;
-    ReportUnexpectedCharacter(*cursor_);
+    ReportUnexpectedToken(JsonToken::ILLEGAL,
+                          MessageTemplate::kJsonParseBadControlCharacter);
     break;
   }
 

test/mjsunit/json-errors.js

@@ -24,7 +24,7 @@ var s = `{"a\u03A9 `;
 TryParse(s, "Unterminated string in JSON at position 5");
 
 var s = `{"a\nb":"b"}`;
-TryParse(s, "Unexpected token '\n', \"{\"a\nb\":\"b\"}\" is not valid JSON");
+TryParse(s, "Bad control character in string literal in JSON at position 3");
 
 var s = `{"a\nb":"b\u03A9"}`;
-TryParse(s, "Unexpected token '\n', \"{\"a\nb\":\"b\u03A9\"}\" is not valid JSON");
+TryParse(s, "Bad control character in string literal in JSON at position 3");

test/mjsunit/messages.js

@@ -528,6 +528,16 @@ test(function() {
   JSON.parse('{"b" : "\\a"}');
 }, "Bad escaped character in JSON at position 9", SyntaxError);
 
+// kJsonParseBadControlCharacter
+test(function() {
+  JSON.parse('"a\bz"');
+}, "Bad control character in string literal in JSON at position 2", SyntaxError);
+
+// kJsonParseBadUnicodeEscape
+test(function() {
+  JSON.parse("[\"\\t\\u");
+}, "Bad Unicode escape in JSON at position 6", SyntaxError);
+
 // kJsonParseNoNumberAfterMinusSign
 test(function() {
   JSON.parse('-');