resolve double-unescaping of CSV fields

Author: mythz

src/ServiceStack.Text/CsvReader.cs

@@ -71,7 +71,7 @@ public static List<string> ParseFields(string line, Func<string,string> parseFn)
             while (++i <= len)
             {
                 var value = EatValue(line, ref i);
-                to.Add(parseFn != null ? parseFn(value) : value);
+                to.Add(parseFn != null ? parseFn(value.FromCsvField()) : value.FromCsvField());
             }
 
             return to;

src/ServiceStack.Text/CsvSerializer.cs

@@ -151,18 +151,27 @@ public static T DeserializeFromReader<T>(TextReader reader)
 
         public static T DeserializeFromString<T>(string text)
         {
-            if (string.IsNullOrEmpty(text)) return default(T);
+            if (string.IsNullOrEmpty(text)) return default;
             var results = CsvSerializer<T>.ReadObject(text);
             return ConvertFrom<T>(results);
         }
 
         public static object DeserializeFromString(Type type, string text)
         {
             if (string.IsNullOrEmpty(text)) return null;
-            var fn = GetReadFn(type);
-            var result = fn(text);
-            var converted = ConvertFrom(type, result);
-            return converted;
+            var hold = JsState.IsCsv;
+            JsState.IsCsv = true;
+            try
+            {
+                var fn = GetReadFn(type);
+                var result = fn(text);
+                var converted = ConvertFrom(type, result);
+                return converted;
+            }
+            finally
+            {
+                JsState.IsCsv = hold;
+            }
         }
 
         public static void WriteLateBoundObject(TextWriter writer, object value)

src/ServiceStack.Text/Jsv/JsvTypeSerializer.cs

@@ -259,12 +259,16 @@ public void WriteEnum(TextWriter writer, object enumValue)
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public object UnescapeStringAsObject(ReadOnlySpan<char> value)
         {
-            return value.FromCsvField().Value();
+            return UnescapeSafeString(value).Value();
         }
 
-        public string UnescapeSafeString(string value) => value.FromCsvField();
+        public string UnescapeSafeString(string value) => JsState.IsCsv
+            ? value
+            : value.FromCsvField();
 
-        public ReadOnlySpan<char> UnescapeSafeString(ReadOnlySpan<char> value) => value.FromCsvField();
+        public ReadOnlySpan<char> UnescapeSafeString(ReadOnlySpan<char> value) => JsState.IsCsv
+            ? value // already unescaped in CsvReader.ParseFields()
+            : value.FromCsvField();
 
         public string ParseRawString(string value) => value;
 

tests/ServiceStack.Text.Tests/CsvSerializerTests.cs

@@ -116,7 +116,7 @@ public void Does_parse_fields()
         }
 
         [Test]
-        public void Does_parse_fileds_with_unmatchedJsMark()
+        public void Does_parse_fields_with_unmatchedJsMark()
         {
             Assert.That(CsvReader.ParseFields("{A,B"), Is.EqualTo(new[] { "{A", "B" }));
             Assert.That(CsvReader.ParseFields("{A},B"), Is.EqualTo(new[] { "{A}", "B" }));