Fix nullExamples

src/Swashbuckle.AspNetCore.SwaggerGen/XmlComments/XmlCommentsExampleHelper.cs

@@ -17,10 +17,27 @@
             value.HasFlag(JsonSchemaType.String) &&
             !value.HasFlag(JsonSchemaType.Null);
 
+        if (string.Equals(exampleString, "null"))
+        {
+
+            return type is { } jsonSchema && jsonSchema.HasFlag(JsonSchemaType.Null) ? JsonNullSentinel.JsonNull : null;
+        }
+
         if (isStringType)
         {
-            return string.Equals(exampleString, "null") ? JsonNullSentinel.JsonNull : JsonValue.Create(exampleString);
+            return JsonValue.Create(exampleString);
+        if (string.Equals(exampleString, "null"))
+        {
+            return type is { } jsonSchema && jsonSchema.HasFlag(JsonSchemaType.Null) ? JsonNullSentinel.JsonNull : null;
         }
+
+   var isStringType = type is { } value &&
+       value.HasFlag(JsonSchemaType.String) &&
+       !value.HasFlag(JsonSchemaType.Null);
+   if (isStringType)
+   {
+        return JsonValue.Create(exampleString);
+   }
 
         // HACK If the value is a string, but we can't detect it as one, then
         // if parsing it fails, assume it is a string that isn't quoted. There's
@@ -34,4 +51,4 @@
             return JsonValue.Create(exampleString);
         }
     }
 }

test/Swashbuckle.AspNetCore.IntegrationTests/snapshots/10_0/VerifyTests.SwaggerEndpoint_ReturnsValidSwaggerJson_startupType=Basic.Startup_swaggerRequestUri=v1.verified.txt

@@ -801,10 +801,8 @@
             "description": "3-letter ISO country code",
             "required": true,
             "schema": {
-              "type": "string",
-              "example": null
-            },
-            "example": null
+              "type": "string"
+            }
           },
           {
             "name": "city",

test/Swashbuckle.AspNetCore.IntegrationTests/snapshots/8_0/VerifyTests.SwaggerEndpoint_ReturnsValidSwaggerJson_startupType=Basic.Startup_swaggerRequestUri=v1.verified.txt

@@ -801,10 +801,8 @@
             "description": "3-letter ISO country code",
             "required": true,
             "schema": {
-              "type": "string",
-              "example": null
-            },
-            "example": null
+              "type": "string"
+            }
           },
           {
             "name": "city",

test/Swashbuckle.AspNetCore.IntegrationTests/snapshots/9_0/VerifyTests.SwaggerEndpoint_ReturnsValidSwaggerJson_startupType=Basic.Startup_swaggerRequestUri=v1.verified.txt

@@ -801,10 +801,8 @@
             "description": "3-letter ISO country code",
             "required": true,
             "schema": {
-              "type": "string",
-              "example": null
-            },
-            "example": null
+              "type": "string"
+            }
           },
           {
             "name": "city",

test/Swashbuckle.AspNetCore.SwaggerGen.Test/Fixtures/XmlAnnotatedRecord.cs

@@ -2,6 +2,7 @@
 
 namespace Swashbuckle.AspNetCore.SwaggerGen.Test;
 
+#nullable enable
 /// <summary>
 /// Summary for XmlAnnotatedRecord
 /// </summary>
@@ -13,10 +14,26 @@ namespace Swashbuckle.AspNetCore.SwaggerGen.Test;
 /// <param name="DateTimeProperty" example="6/22/2022 12:00:00 AM">Summary for DateTimeProperty</param>
 /// <param name="EnumProperty" example="2">Summary for EnumProperty</param>
 /// <param name="GuidProperty" example="d3966535-2637-48fa-b911-e3c27405ee09">Summary for GuidProperty</param>
-/// <param name="StringPropertyWithNullExample" example="null">Summary for Nullable StringPropertyWithNullExample</param>
+/// <param name="NullableStringPropertyWithNullExample" example="null">Summary for NullableStringPropertyWithNullExample</param>
+/// <param name="StringPropertyWithNullExample" example="null">Summary for StringPropertyWithNullExample</param>
+/// <param name="NullableIntPropertyWithNotNullExample" example="3">Summary for NullableIntPropertyWithNotNullExample</param>
+/// <param name="NullableIntPropertyWithNullExample" example="null">Summary for NullableIntPropertyWithNullExample</param>
+/// <param name="IntPropertyWithNullExample" example="null">Summary for IntPropertyWithNullExample</param>
+/// <param name="NullableGuidPropertyWithNullExample" example="null">Summary for NullableGuidPropertyWithNullExample</param>
+/// <param name="GuidPropertyWithNullExample" example="null">Summary for GuidPropertyWithNullExample</param>
 /// <param name="StringProperty" example="Example for StringProperty">Summary for StringProperty</param>
 /// <param name="StringPropertyWithUri" example="https://test.com/a?b=1&amp;c=2">Summary for StringPropertyWithUri</param>
 /// <param name="ObjectProperty" example="{&quot;prop1&quot;: 1, &quot;prop2&quot;: &quot;foobar&quot;}">Summary for ObjectProperty</param>
+/// <param name="ObjectPropertyNullExample" example="null">Summary for ObjectPropertyNullExample</param>
+/// <param name="NullableObjectPropertyNullExample" example="null">Summary for NullableObjectPropertyNullExample</param>
+/// <param name="NullableDateTimePropertyWithNullExample" example="null">Summary for NullableDateTimePropertyWithNullExample</param>
+/// <param name="DateTimePropertyWithNullExample" example="null">Summary for DateTimePropertyWithNullExample</param>
+/// <param name="NullableTimeOnlyPropertyWithNullExample" example="null">Summary for NullableTimeOnlyPropertyWithNullExample</param>
+/// <param name="TimeOnlyPropertyWithNullExample" example="null">Summary for TimeOnlyPropertyWithNullExample</param>
+/// <param name="NullableTimeSpanPropertyWithNullExample" example="null">Summary for NullableTimeSpanPropertyWithNullExample</param>
+/// <param name="TimeSpanPropertyWithNullExample" example="null">Summary for TimeSpanPropertyWithNullExample</param>
+/// <param name="NullableDateOnlyPropertyWithNullExample" example="null">Summary for NullableDateOnlyPropertyWithNullExample</param>
+/// <param name="DateOnlyPropertyWithNullExample" example="null">Summary for DateOnlyPropertyWithNullExample</param>
 public record XmlAnnotatedRecord(
     bool BoolProperty,
     int IntProperty,
@@ -26,8 +43,24 @@ public record XmlAnnotatedRecord(
     DateTime DateTimeProperty,
     IntEnum EnumProperty,
     Guid GuidProperty,
+    string? NullableStringPropertyWithNullExample,
     string StringPropertyWithNullExample,
+    int? NullableIntPropertyWithNotNullExample,
+    int? NullableIntPropertyWithNullExample,
+    int IntPropertyWithNullExample,
+    Guid? NullableGuidPropertyWithNullExample,
+    Guid GuidPropertyWithNullExample,
     string StringProperty,
     string StringPropertyWithUri,
-    object ObjectProperty
+    object ObjectProperty,
+    object ObjectPropertyNullExample,
+    object? NullableObjectPropertyNullExample,
+    DateTime? NullableDateTimePropertyWithNullExample,
+    DateTime DateTimePropertyWithNullExample,
+    TimeOnly? NullableTimeOnlyPropertyWithNullExample,
+    TimeOnly TimeOnlyPropertyWithNullExample,
+    TimeSpan? NullableTimeSpanPropertyWithNullExample,
+    TimeSpan TimeSpanPropertyWithNullExample,
+    DateOnly? NullableDateOnlyPropertyWithNullExample,
+    DateOnly DateOnlyPropertyWithNullExample
     );

test/Swashbuckle.AspNetCore.SwaggerGen.Test/Fixtures/XmlAnnotatedType.cs

@@ -1,7 +1,7 @@
 using Swashbuckle.AspNetCore.TestSupport;
 
 namespace Swashbuckle.AspNetCore.SwaggerGen.Test;
-
+#nullable enable
 /// <summary>
 /// Summary for XmlAnnotatedType
 /// </summary>
@@ -62,28 +62,46 @@ public class XmlAnnotatedType
     public Guid GuidProperty { get; set; }
 
     /// <summary>
-    /// Summary for Nullable StringPropertyWithNullExample
+    /// Summary for NullableStringPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+    public string? NullableStringPropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for StringPropertyWithNullExample
     /// </summary>
     /// <example>null</example>
-    public string StringPropertyWithNullExample { get; set; }
+    public required string StringPropertyWithNullExample { get; set; }
 
     /// <summary>
     /// Summary for StringProperty
     /// </summary>
     /// <example>Example for StringProperty</example>
-    public string StringProperty { get; set; }
+    public required string StringProperty { get; set; }
 
     /// <summary>
     /// Summary for StringPropertyWithUri
     /// </summary>
     /// <example><![CDATA[https://test.com/a?b=1&c=2]]></example>
-    public string StringPropertyWithUri { get; set; }
+    public required string StringPropertyWithUri { get; set; }
 
     /// <summary>
     /// Summary for ObjectProperty
     /// </summary>
     /// <example>{"prop1": 1, "prop2": "foobar"}</example>
-    public object ObjectProperty { get; set; }
+    public required object ObjectProperty { get; set; }
+
+    /// <summary>
+    /// Summary for ObjectPropertyNullExample
+    /// </summary>
+    /// <example>null</example>
+    public required object ObjectPropertyNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for NullableObjectPropertyNullExample
+    /// </summary>
+    /// <example>null</example>
+    public object? NullableObjectPropertyNullExample { get; set; }
 
     /// <summary>
     /// Summary for AcceptsNothing
@@ -124,20 +142,109 @@ public void AcceptsConstructedOfConstructedGenericType(
     public void AcceptsArrayOfConstructedGenericType(int?[] param)
     {
     }
+    ///
+    /// <summary>
+    /// >Summary for NullableIntPropertyWithNotNullExample
+    /// </summary>
+    /// <example>3</example>
+    public int? NullableIntPropertyWithNotNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for NullableIntPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+    public int? NullableIntPropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for IntPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public int IntPropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for NullableGuidPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public Guid? NullableGuidPropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for GuidPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public Guid GuidPropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for NullableDateTimePropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public DateTime? NullableDateTimePropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for DateTimePropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public DateTime DateTimePropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for NullableTimeOnlyPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public TimeOnly? NullableTimeOnlyPropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for TimeOnlyPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public TimeOnly TimeOnlyPropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for NullableTimeSpanPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public TimeSpan? NullableTimeSpanPropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for TimeSpanPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public TimeSpan TimeSpanPropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for NullableDateOnlyPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public DateOnly? NullableDateOnlyPropertyWithNullExample { get; set; }
+
+    /// <summary>
+    /// Summary for DateOnlyPropertyWithNullExample
+    /// </summary>
+    /// <example>null</example>
+
+    public DateOnly DateOnlyPropertyWithNullExample { get; set; }
 
     /// <summary>
     /// Summary for NestedType
     /// </summary>
     public class NestedType
     {
-        public string Property { get; set; }
+        public required string Property { get; set; }
 
         public class InnerNestedType
         {
             /// <summary>
             /// Summary of DoubleNestedType.InnerType.Property
             /// </summary>
-            public string InnerProperty { get; set; }
+            public required string InnerProperty { get; set; }
         }
     }
 }

test/Swashbuckle.AspNetCore.SwaggerGen.Test/XmlComments/XmlCommentsExampleHelperTests.cs

@@ -74,7 +74,7 @@ public void Create_Returns_Null_When_Value_And_Schema_Are_Null()
     [Fact]
     public void Create_Returns_Null_When_Type_String_And_Value_Null_String_Literal()
     {
-        var schema = new OpenApiSchema { Type = JsonSchemaTypes.String };
+        var schema = new OpenApiSchema { Type = JsonSchemaTypes.String | JsonSchemaType.Null };
         schemaRepository.AddDefinition("test", schema);
 
         var example = XmlCommentsExampleHelper.Create(