fix(models): deep copy Servers and Variables in copy constructors

Author: hardikkaurani

src/Microsoft.OpenApi/Models/OpenApiDocument.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Microsoft Corporation. All rights reserved.
+// Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license.
 
 using System;
@@ -143,7 +143,7 @@ public OpenApiDocument(OpenApiDocument? document)
             Info = document?.Info != null ? new(document.Info) : new OpenApiInfo();
             JsonSchemaDialect = document?.JsonSchemaDialect ?? JsonSchemaDialect;
             Self = document?.Self ?? Self;
-            Servers = document?.Servers != null ? [.. document.Servers] : null;
+            Servers = document?.Servers != null ? [.. document.Servers.Select(static s => new OpenApiServer(s))] : null;
             Paths = document?.Paths != null ? new(document.Paths) : [];
             Webhooks = document?.Webhooks != null ? new Dictionary<string, IOpenApiPathItem>(document.Webhooks) : null;
             Components = document?.Components != null ? new(document?.Components) : null;

src/Microsoft.OpenApi/Models/OpenApiOperation.cs

@@ -151,7 +151,7 @@ public OpenApiOperation(OpenApiOperation operation)
             Callbacks = operation.Callbacks != null ? new Dictionary<string, IOpenApiCallback>(operation.Callbacks) : null;
             Deprecated = operation.Deprecated;
             Security = operation.Security != null ? [.. operation.Security] : null;
-            Servers = operation.Servers != null ? [.. operation.Servers] : null;
+            Servers = operation.Servers != null ? [.. operation.Servers.Select(static s => new OpenApiServer(s))] : null;
             Extensions = operation.Extensions != null ? new Dictionary<string, IOpenApiExtension>(operation.Extensions) : null;
             Metadata = operation.Metadata != null ? new Dictionary<string, object>(operation.Metadata) : null;
         }

src/Microsoft.OpenApi/Models/OpenApiServer.cs

@@ -1,8 +1,9 @@
-// Copyright (c) Microsoft Corporation. All rights reserved.
+// Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license.
 
 using System;
 using System.Collections.Generic;
+using System.Linq;
 
 namespace Microsoft.OpenApi
 {
@@ -52,7 +53,7 @@ public OpenApiServer(OpenApiServer server)
             Description = server?.Description ?? Description;
             Name = server?.Name ?? Name;
             Url = server?.Url ?? Url;
-            Variables = server?.Variables != null ? new Dictionary<string, OpenApiServerVariable>(server.Variables) : null;
+            Variables = server?.Variables != null ? server.Variables.ToDictionary(static kvp => kvp.Key, static kvp => new OpenApiServerVariable(kvp.Value)) : null;
             Extensions = server?.Extensions != null ? new Dictionary<string, IOpenApiExtension>(server.Extensions) : null;
         }
 

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

@@ -1,4 +1,4 @@
-// Copyright (c) Microsoft Corporation. All rights reserved.
+// Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. 
 
 using System;
@@ -2753,5 +2753,28 @@ public void GetOperationById_ThrowsOnNullOrEmptyId()
             Assert.Throws<ArgumentNullException>(() => doc.GetOperationById(null!));
             Assert.Throws<ArgumentNullException>(() => doc.GetOperationById(string.Empty));
         }
+
+        [Fact]
+        public void OpenApiDocumentCopyConstructorDeepCopiesServers()
+        {
+            var document = new OpenApiDocument
+            {
+                Servers =
+                [
+                    new OpenApiServer
+                    {
+                        Url = "https://api.example.com",
+                        Description = "Production server"
+                    }
+                ]
+            };
+
+            var copy = new OpenApiDocument(document);
+            Assert.NotNull(copy.Servers);
+            Assert.NotSame(document.Servers[0], copy.Servers[0]);
+
+            copy.Servers[0].Url = "https://staging.example.com";
+            Assert.Equal("https://api.example.com", document.Servers[0].Url);
+        }
     }
 }

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

@@ -995,5 +995,28 @@ public void OpenApiOperationCopyConstructorPreservesImmutableSortedSet()
             var copyNames = copy.Tags.Select(t => t.Name);
             Assert.Equal(["tagC", "tagB", "tagA"], copyNames);
         }
+
+        [Fact]
+        public void OpenApiOperationCopyConstructorDeepCopiesServers()
+        {
+            var operation = new OpenApiOperation
+            {
+                Servers =
+                [
+                    new OpenApiServer
+                    {
+                        Url = "https://api.example.com/v1",
+                        Description = "Operation server"
+                    }
+                ]
+            };
+
+            var copy = new OpenApiOperation(operation);
+            Assert.NotNull(copy.Servers);
+            Assert.NotSame(operation.Servers[0], copy.Servers[0]);
+
+            copy.Servers[0].Url = "https://staging.example.com/v1";
+            Assert.Equal("https://api.example.com/v1", operation.Servers[0].Url);
+        }
     }
 }

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

@@ -1,4 +1,4 @@
-// Copyright (c) Microsoft Corporation. All rights reserved.
+// Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license.
 
 using System.Collections.Generic;
@@ -190,5 +190,36 @@ public void CopyConstructorHandlesNameField()
             Assert.Equal(original.Description, copy.Description);
             Assert.Equal(original.Url, copy.Url);
         }
+
+        [Fact]
+        public void CopyConstructorDeepCopiesVariables()
+        {
+            // Arrange
+            var original = new OpenApiServer
+            {
+                Url = "https://{username}.example.com:{port}",
+                Variables = new Dictionary<string, OpenApiServerVariable>
+                {
+                    ["port"] = new()
+                    {
+                        Default = "8443",
+                        Enum = ["443", "8443"]
+                    }
+                }
+            };
+
+            // Act
+            var copy = new OpenApiServer(original);
+
+            // Assert
+            Assert.NotNull(copy.Variables);
+            Assert.NotSame(original.Variables["port"], copy.Variables["port"]);
+            Assert.NotSame(original.Variables["port"].Enum, copy.Variables["port"].Enum);
+
+            copy.Variables["port"].Default = "9443";
+            copy.Variables["port"].Enum?.Add("9443");
+            Assert.Equal("8443", original.Variables["port"].Default);
+            Assert.DoesNotContain("9443", original.Variables["port"].Enum);
+        }
     }
 }