Merge pull request dotnet#4953 from gewarren/deserialize

Exception changes for Deserialize<char>

Author: gewarren

xml/System.Text.Json/JsonSerializer.xml

@@ -136,7 +136,7 @@ For more information, see [How to serialize and deserialize JSON](/dotnet/standa
         <exception cref="T:System.ArgumentNullException">
           <paramref name="json" /> or <paramref name="returnType" /> is <see langword="null" />.</exception>
         <exception cref="T:System.Text.Json.JsonException">The JSON is invalid.
-          
+
 -or-
 
 <typeparamref name="TValue" /> is not compatible with the JSON.
@@ -201,7 +201,7 @@ For more information, see [How to serialize and deserialize JSON](/dotnet/standa
         <exception cref="T:System.ArgumentNullException">
           <paramref name="returnType" /> is <see langword="null" />.</exception>
         <exception cref="T:System.Text.Json.JsonException">The JSON is invalid.
-          
+
 -or-
 
 <typeparamref name="returnType" /> is not compatible with the JSON.
@@ -306,6 +306,8 @@ For more information, see [How to serialize and deserialize JSON](/dotnet/standa
 
 ]]></format>
         </remarks>
+        <exception cref="T:System.IndexOutOfRangeException">
+          .NET Core 3.0 only: <typeparamref name="TValue" /> is <see cref="T:System.Char" /> and <paramref name="json" /> is an empty string.</exception>
         <exception cref="T:System.ArgumentNullException">
           <paramref name="json" /> is <see langword="null" />.</exception>
         <exception cref="T:System.Text.Json.JsonException">The JSON is invalid.
@@ -316,7 +318,11 @@ For more information, see [How to serialize and deserialize JSON](/dotnet/standa
 
 -or-
 
-There is remaining data in the string beyond a single JSON value.</exception>
+There is remaining data in the string beyond a single JSON value.
+
+-or-
+
+.NET Core 3.1 and later versions only: <typeparamref name="TValue" /> is <see cref="T:System.Char" /> and <paramref name="json" /> is a null reference (<code>JsonSerializer.Deserialize&lt;char&gt;("null");</code>) or an empty string.</exception>
         <exception cref="T:System.NotSupportedException">There is no compatible <see cref="System.Text.Json.Serialization.JsonConverter" /> for <typeparamref name="TValue" /> or its serializable members.</exception>
       </Docs>
     </Member>
@@ -355,15 +361,15 @@ There is remaining data in the string beyond a single JSON value.</exception>
 ## Remarks
 
 If the <xref:System.Text.Json.Utf8JsonReader.TokenType> property of `reader` is <xref:System.Text.Json.JsonTokenType.PropertyName?displayProperty=nameWithType> or <xref:System.Text.Json.JsonTokenType.None?displayProperty=nameWithType>, the reader will be advanced by one call to <xref:System.Text.Json.Utf8JsonReader.Read?displayProperty=nameWithType> to determine the start of the value.
-               
+
 Upon completion of this method, `reader` will be positioned at the final token in the JSON value. If an exception is thrown, the reader is reset to the state it was in when the method was called.
-               
+
 This method makes a copy of the data the reader acted on, so there is no caller requirement to maintain data integrity beyond the return of this method.
-               
+
 The <xref:System.Text.Json.JsonReaderOptions> used to create the instance of the <xref:System.Text.Json.Utf8JsonReader> take precedence over the <xref:System.Text.Json.JsonSerializerOptions> when they conflict. Hence, <xref:System.Text.Json.JsonReaderOptions.AllowTrailingCommas?displayProperty=nameWithType>, <xref:System.Text.Json.JsonReaderOptions.MaxDepth?displayProperty=nameWithType>, and <xref:System.Text.Json.JsonReaderOptions.CommentHandling?displayProperty=nameWithType> are used while reading.
 
 For more information, see [How to serialize and deserialize JSON](/dotnet/standard/serialization/system-text-json-how-to).
-               
+
           ]]></format>
         </remarks>
         <exception cref="T:System.Text.Json.JsonException">The JSON is invalid.