OpenApiOperation constructor preserve null

src/Microsoft.OpenApi/Models/OpenApiOperation.cs

@@ -116,13 +116,13 @@ public OpenApiOperation() {}
         /// </summary>
         public OpenApiOperation(OpenApiOperation operation)
         {
-            Tags = new List<OpenApiTag>(operation?.Tags);
+            Tags = operation?.Tags != null ? new List<OpenApiTag>(operation?.Tags) : null;
             Summary = operation?.Summary ?? Summary;
             Description = operation?.Description ?? Description;
             ExternalDocs = operation?.ExternalDocs != null ? new(operation?.ExternalDocs) : null;
             OperationId = operation?.OperationId ?? OperationId;
             Parameters = operation?.Parameters != null ? new List<OpenApiParameter>(operation.Parameters) : null;
-            RequestBody = new(operation?.RequestBody);
+            RequestBody = operation?.RequestBody != null ? new(operation?.RequestBody) : null;
             Responses = operation?.Responses != null ? new(operation?.Responses) : null;
             Callbacks = operation?.Callbacks != null ? new Dictionary<string, OpenApiCallback>(operation.Callbacks) : null;
             Deprecated = operation?.Deprecated ?? Deprecated;

src/Microsoft.OpenApi/Models/OpenApiParameter.cs

@@ -243,11 +243,11 @@ public void SerializeAsV3WithoutReference(IOpenApiWriter writer)
             // style
             if (_style.HasValue)
             {
-                writer.WriteProperty(OpenApiConstants.Style, Style.Value.GetDisplayName());
+                writer.WriteProperty(OpenApiConstants.Style, _style.Value.GetDisplayName());
             }
 
             // explode
-            writer.WriteProperty(OpenApiConstants.Explode, Explode, Style.HasValue && Style.Value == ParameterStyle.Form);
+            writer.WriteProperty(OpenApiConstants.Explode, _explode, _style.HasValue && _style.Value == ParameterStyle.Form);
 
             // allowReserved
             writer.WriteProperty(OpenApiConstants.AllowReserved, AllowReserved, false);

test/Microsoft.OpenApi.Tests/Models/OpenApiDocumentTests.SerializeAdvancedDocumentWithReferenceAsV3JsonWorks_produceTerseOutput=True.verified.txt

@@ -1 +1 @@
-{"openapi":"3.0.1","info":{"title":"Swagger Petstore (Simple)","description":"A sample API that uses a petstore as an example to demonstrate features in the swagger-2.0 specification","termsOfService":"http://helloreverb.com/terms/","contact":{"name":"Swagger API team","url":"http://swagger.io","email":"[email protected]"},"license":{"name":"MIT","url":"http://opensource.org/licenses/MIT"},"version":"1.0.0"},"servers":[{"url":"http://petstore.swagger.io/api"}],"paths":{"/pets":{"get":{"description":"Returns all pets from the system that the user has access to","operationId":"findPets","parameters":[{"name":"tags","in":"query","description":"tags to filter by","style":"form","schema":{"type":"array","items":{"type":"string"}}},{"name":"limit","in":"query","description":"maximum number of results to return","style":"form","schema":{"type":"integer","format":"int32"}}],"responses":{"200":{"description":"pet response","content":{"application/json":{"schema":{"type":"array","items":{"$ref":"#/components/schemas/pet"}}},"application/xml":{"schema":{"type":"array","items":{"$ref":"#/components/schemas/pet"}}}}},"4XX":{"description":"unexpected client error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}},"5XX":{"description":"unexpected server error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}}}},"post":{"description":"Creates a new pet in the store.  Duplicates are allowed","operationId":"addPet","requestBody":{"description":"Pet to add to the store","content":{"application/json":{"schema":{"$ref":"#/components/schemas/newPet"}}},"required":true},"responses":{"200":{"description":"pet response","content":{"application/json":{"schema":{"$ref":"#/components/schemas/pet"}}}},"4XX":{"description":"unexpected client error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}},"5XX":{"description":"unexpected server error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}}}}},"/pets/{id}":{"get":{"description":"Returns a user based on a single ID, if the user does not have access to the pet","operationId":"findPetById","parameters":[{"name":"id","in":"path","description":"ID of pet to fetch","required":true,"style":"simple","schema":{"type":"integer","format":"int64"}}],"responses":{"200":{"description":"pet response","content":{"application/json":{"schema":{"$ref":"#/components/schemas/pet"}},"application/xml":{"schema":{"$ref":"#/components/schemas/pet"}}}},"4XX":{"description":"unexpected client error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}},"5XX":{"description":"unexpected server error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}}}},"delete":{"description":"deletes a single pet based on the ID supplied","operationId":"deletePet","parameters":[{"name":"id","in":"path","description":"ID of pet to delete","required":true,"style":"simple","schema":{"type":"integer","format":"int64"}}],"responses":{"204":{"description":"pet deleted"},"4XX":{"description":"unexpected client error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}},"5XX":{"description":"unexpected server error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}}}}}},"components":{"schemas":{"pet":{"required":["id","name"],"type":"object","properties":{"id":{"type":"integer","format":"int64"},"name":{"type":"string"},"tag":{"type":"string"}}},"newPet":{"required":["name"],"type":"object","properties":{"id":{"type":"integer","format":"int64"},"name":{"type":"string"},"tag":{"type":"string"}}},"errorModel":{"required":["code","message"],"type":"object","properties":{"code":{"type":"integer","format":"int32"},"message":{"type":"string"}}}}}}
+{"openapi":"3.0.1","info":{"title":"Swagger Petstore (Simple)","description":"A sample API that uses a petstore as an example to demonstrate features in the swagger-2.0 specification","termsOfService":"http://helloreverb.com/terms/","contact":{"name":"Swagger API team","url":"http://swagger.io","email":"[email protected]"},"license":{"name":"MIT","url":"http://opensource.org/licenses/MIT"},"version":"1.0.0"},"servers":[{"url":"http://petstore.swagger.io/api"}],"paths":{"/pets":{"get":{"description":"Returns all pets from the system that the user has access to","operationId":"findPets","parameters":[{"name":"tags","in":"query","description":"tags to filter by","schema":{"type":"array","items":{"type":"string"}}},{"name":"limit","in":"query","description":"maximum number of results to return","schema":{"type":"integer","format":"int32"}}],"responses":{"200":{"description":"pet response","content":{"application/json":{"schema":{"type":"array","items":{"$ref":"#/components/schemas/pet"}}},"application/xml":{"schema":{"type":"array","items":{"$ref":"#/components/schemas/pet"}}}}},"4XX":{"description":"unexpected client error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}},"5XX":{"description":"unexpected server error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}}}},"post":{"description":"Creates a new pet in the store.  Duplicates are allowed","operationId":"addPet","requestBody":{"description":"Pet to add to the store","content":{"application/json":{"schema":{"$ref":"#/components/schemas/newPet"}}},"required":true},"responses":{"200":{"description":"pet response","content":{"application/json":{"schema":{"$ref":"#/components/schemas/pet"}}}},"4XX":{"description":"unexpected client error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}},"5XX":{"description":"unexpected server error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}}}}},"/pets/{id}":{"get":{"description":"Returns a user based on a single ID, if the user does not have access to the pet","operationId":"findPetById","parameters":[{"name":"id","in":"path","description":"ID of pet to fetch","required":true,"schema":{"type":"integer","format":"int64"}}],"responses":{"200":{"description":"pet response","content":{"application/json":{"schema":{"$ref":"#/components/schemas/pet"}},"application/xml":{"schema":{"$ref":"#/components/schemas/pet"}}}},"4XX":{"description":"unexpected client error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}},"5XX":{"description":"unexpected server error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}}}},"delete":{"description":"deletes a single pet based on the ID supplied","operationId":"deletePet","parameters":[{"name":"id","in":"path","description":"ID of pet to delete","required":true,"schema":{"type":"integer","format":"int64"}}],"responses":{"204":{"description":"pet deleted"},"4XX":{"description":"unexpected client error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}},"5XX":{"description":"unexpected server error","content":{"text/html":{"schema":{"$ref":"#/components/schemas/errorModel"}}}}}}}},"components":{"schemas":{"pet":{"required":["id","name"],"type":"object","properties":{"id":{"type":"integer","format":"int64"},"name":{"type":"string"},"tag":{"type":"string"}}},"newPet":{"required":["name"],"type":"object","properties":{"id":{"type":"integer","format":"int64"},"name":{"type":"string"},"tag":{"type":"string"}}},"errorModel":{"required":["code","message"],"type":"object","properties":{"code":{"type":"integer","format":"int32"},"message":{"type":"string"}}}}}}

test/Microsoft.OpenApi.Tests/Models/OpenApiDocumentTests.SerializeDuplicateExtensionsAsV3JsonWorks_produceTerseOutput=True.verified.txt

@@ -1 +1 @@
-{"openapi":"3.0.1","info":{"title":"Swagger Petstore (Simple)","description":"A sample API that uses a petstore as an example to demonstrate features in the swagger-2.0 specification","version":"1.0.0"},"servers":[{"url":"http://petstore.swagger.io/api"}],"paths":{"/add/{operand1}/{operand2}":{"get":{"operationId":"addByOperand1AndByOperand2","parameters":[{"name":"operand1","in":"path","description":"The first operand","required":true,"style":"simple","schema":{"type":"integer","my-extension":4},"my-extension":4},{"name":"operand2","in":"path","description":"The second operand","required":true,"style":"simple","schema":{"type":"integer","my-extension":4},"my-extension":4}],"responses":{"200":{"description":"pet response","content":{"application/json":{"schema":{"type":"array","items":{"required":["id","name"],"type":"object","properties":{"id":{"type":"integer","format":"int64"},"name":{"type":"string"},"tag":{"type":"string"}}}}}}}}}}}}
+{"openapi":"3.0.1","info":{"title":"Swagger Petstore (Simple)","description":"A sample API that uses a petstore as an example to demonstrate features in the swagger-2.0 specification","version":"1.0.0"},"servers":[{"url":"http://petstore.swagger.io/api"}],"paths":{"/add/{operand1}/{operand2}":{"get":{"operationId":"addByOperand1AndByOperand2","parameters":[{"name":"operand1","in":"path","description":"The first operand","required":true,"schema":{"type":"integer","my-extension":4},"my-extension":4},{"name":"operand2","in":"path","description":"The second operand","required":true,"schema":{"type":"integer","my-extension":4},"my-extension":4}],"responses":{"200":{"description":"pet response","content":{"application/json":{"schema":{"type":"array","items":{"required":["id","name"],"type":"object","properties":{"id":{"type":"integer","format":"int64"},"name":{"type":"string"},"tag":{"type":"string"}}}}}}}}}}}}

test/Microsoft.OpenApi.Tests/Models/OpenApiOperationTests.cs

@@ -6,6 +6,7 @@
 using FluentAssertions;
 using Microsoft.OpenApi.Extensions;
 using Microsoft.OpenApi.Models;
+using NuGet.Frameworks;
 using Xunit;
 using Xunit.Abstractions;
 
@@ -793,5 +794,58 @@ public void EnsureOpenApiOperationCopyConstructorCopiesResponsesObject()
             Assert.NotNull(operation.Responses);
             Assert.Equal(2, operation.Responses.Count);
         }
+
+        [Fact]
+        public void EnsureOpenApiOperationCopyConstructorCopiesNull()
+        {
+            // Arrange
+            _basicOperation.Parameters = null;
+            _basicOperation.Tags = null;
+            _basicOperation.Responses = null;
+            _basicOperation.Callbacks = null;
+            _basicOperation.Security = null;
+            _basicOperation.Servers = null;
+            _basicOperation.Extensions = null;
+
+            // Act
+            var operation = new OpenApiOperation(_basicOperation);
+
+            // Assert
+            Assert.Null(operation.Tags);
+            Assert.Null(operation.Summary);
+            Assert.Null(operation.Description);
+            Assert.Null(operation.ExternalDocs);
+            Assert.Null(operation.OperationId);
+            Assert.Null(operation.Parameters);
+            Assert.Null(operation.RequestBody);
+            Assert.Null(operation.Responses);
+            Assert.Null(operation.Callbacks);
+            Assert.Null(operation.Security);
+            Assert.Null(operation.Servers);
+            Assert.Null(operation.Extensions);
+        }
+
+        [Fact]
+        public void EnsureOpenApiOperationCopyConstructor_SerializationResultsInSame()
+        {
+            var operations = new[]
+            {
+                _basicOperation,
+                _operationWithBody,
+                _operationWithFormData,
+                _advancedOperationWithTagsAndSecurity
+            };
+
+            foreach (var operation in operations)
+            {
+                // Act
+                var expected = operation.SerializeAsJson(OpenApiSpecVersion.OpenApi3_0);
+                var openApiOperation = new OpenApiOperation(operation);
+                var actual = openApiOperation.SerializeAsJson(OpenApiSpecVersion.OpenApi3_0);
+
+                // Assert
+                actual.Should().Be(expected);
+            }
+        }
     }
 }

test/Microsoft.OpenApi.Tests/Models/OpenApiParameterTests.SerializeReferencedParameterAsV3JsonWithoutReferenceWorksAsync_produceTerseOutput=True.verified.txt

@@ -1 +1 @@
-{"name":"name1","in":"path","style":"simple"}
+{"name":"name1","in":"path"}