From 9da8c781336bf773705530646c20969df1dc4b36 Mon Sep 17 00:00:00 2001
From: Idan Horowitz <idan.horowitz@gmail.com>
Date: Thu, 24 Feb 2022 19:15:31 +0200
Subject: [PATCH] AK: Add a try variant of
 StringBuilder::append_escaped_for_json

This will allow us to make a fallible version of the JSON serializers.
---
 AK/StringBuilder.cpp | 20 +++++++++++++-------
 AK/StringBuilder.h   |  1 +
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/AK/StringBuilder.cpp b/AK/StringBuilder.cpp
index e537e57c19..58460911f7 100644
--- a/AK/StringBuilder.cpp
+++ b/AK/StringBuilder.cpp
@@ -171,31 +171,37 @@ void StringBuilder::append_as_lowercase(char ch)
 }
 
 void StringBuilder::append_escaped_for_json(StringView string)
+{
+    MUST(try_append_escaped_for_json(string));
+}
+
+ErrorOr<void> StringBuilder::try_append_escaped_for_json(StringView string)
 {
     for (auto ch : string) {
         switch (ch) {
         case '\b':
-            append("\\b");
+            TRY(try_append("\\b"));
             break;
         case '\n':
-            append("\\n");
+            TRY(try_append("\\n"));
             break;
         case '\t':
-            append("\\t");
+            TRY(try_append("\\t"));
             break;
         case '\"':
-            append("\\\"");
+            TRY(try_append("\\\""));
             break;
         case '\\':
-            append("\\\\");
+            TRY(try_append("\\\\"));
             break;
         default:
             if (ch >= 0 && ch <= 0x1f)
-                appendff("\\u{:04x}", ch);
+                TRY(try_appendff("\\u{:04x}", ch));
             else
-                append(ch);
+                TRY(try_append(ch));
         }
     }
+    return {};
 }
 
 }
diff --git a/AK/StringBuilder.h b/AK/StringBuilder.h
index 869c20446c..9021e79eec 100644
--- a/AK/StringBuilder.h
+++ b/AK/StringBuilder.h
@@ -35,6 +35,7 @@ public:
         return vformat(*this, fmtstr.view(), variadic_format_params);
     }
     ErrorOr<void> try_append(char const*, size_t);
+    ErrorOr<void> try_append_escaped_for_json(StringView);
 
     void append(StringView);
 #ifndef KERNEL