Add a new OpenIddictMessage constructor accepting non-nullable immutable arrays

Directory.Packages.props

@@ -53,7 +53,7 @@
       Note: OpenIddict uses Meziantou.Polyfill to dynamically generate polyfills for types that are not available
       on some of the targeted TFMs (e.g Index, Range or nullable attributes on .NET Framework/.NET Standard).
     -->
-    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.83" />
+    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.101" />
   </ItemGroup>
 
   <!--
@@ -110,7 +110,7 @@
       Note: OpenIddict uses Meziantou.Polyfill to dynamically generate polyfills for types that are not available
       on some of the targeted TFMs (e.g Index, Range or nullable attributes on .NET Framework/.NET Standard).
     -->
-    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.83" />
+    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.101" />
   </ItemGroup>
 
   <!--
@@ -202,7 +202,7 @@
       Note: OpenIddict uses Meziantou.Polyfill to dynamically generate polyfills for types that are not available
       on some of the targeted TFMs (e.g Index, Range or nullable attributes on .NET Framework/.NET Standard).
     -->
-    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.83" />
+    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.101" />
   </ItemGroup>
 
   <!--
@@ -249,7 +249,7 @@
       Note: OpenIddict uses Meziantou.Polyfill to dynamically generate polyfills for types that are not available
       on some of the targeted TFMs (e.g Index, Range or nullable attributes on .NET Framework/.NET Standard).
     -->
-    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.83" />
+    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.101" />
   </ItemGroup>
 
   <!--
@@ -295,7 +295,7 @@
       Note: OpenIddict uses Meziantou.Polyfill to dynamically generate polyfills for types that are not available
       on some of the targeted TFMs (e.g Index, Range or nullable attributes on .NET Framework/.NET Standard).
     -->
-    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.83" />
+    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.101" />
   </ItemGroup>
 
   <!--
@@ -354,7 +354,7 @@
       Note: OpenIddict uses Meziantou.Polyfill to dynamically generate polyfills for types that are not available
       on some of the targeted TFMs (e.g Index, Range or nullable attributes on .NET Framework/.NET Standard).
     -->
-    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.83" />
+    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.101" />
   </ItemGroup>
 
   <!--
@@ -405,7 +405,7 @@
       Note: OpenIddict uses Meziantou.Polyfill to dynamically generate polyfills for types that are not available
       on some of the targeted TFMs (e.g Index, Range or nullable attributes on .NET Framework/.NET Standard).
     -->
-    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.83" />
+    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.101" />
   </ItemGroup>
 
   <!--
@@ -446,7 +446,7 @@
       Note: OpenIddict uses Meziantou.Polyfill to dynamically generate polyfills for types that are not available
       on some of the targeted TFMs (e.g Index, Range or nullable attributes on .NET Framework/.NET Standard).
     -->
-    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.83" />
+    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.101" />
   </ItemGroup>
 
   <!--
@@ -468,7 +468,7 @@
       Note: OpenIddict uses Meziantou.Polyfill to dynamically generate polyfills for types that are not available
       on some of the targeted TFMs (e.g Index, Range or nullable attributes on .NET Framework/.NET Standard).
     -->
-    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.83" />
+    <GlobalPackageReference Include="Meziantou.Polyfill" Condition=" '$(IncludePolyfills)' != 'false' " Version="1.0.101" />
   </ItemGroup>
 
 </Project>

sandbox/OpenIddict.Sandbox.AspNet.Client/OpenIddict.Sandbox.AspNet.Client.csproj

@@ -7,7 +7,6 @@
     <MvcBuildViews>false</MvcBuildViews>
     <ImplicitUsings>disable</ImplicitUsings>
     <NoWarn>CA3147</NoWarn>
-    <IncludePolyfills>false</IncludePolyfills>
   </PropertyGroup>
 
   <ItemGroup>

sandbox/OpenIddict.Sandbox.AspNet.Server/OpenIddict.Sandbox.AspNet.Server.csproj

@@ -7,7 +7,6 @@
     <MvcBuildViews>false</MvcBuildViews>
     <ImplicitUsings>disable</ImplicitUsings>
     <NoWarn>CA3147</NoWarn>
-    <IncludePolyfills>false</IncludePolyfills>
   </PropertyGroup>
 
   <ItemGroup>

sandbox/OpenIddict.Sandbox.AspNet.Server/Views/Authorization/Authorize.cshtml

@@ -14,10 +14,10 @@
         foreach (var parameter in string.Equals(Request.HttpMethod, "POST", StringComparison.OrdinalIgnoreCase) ?
             from name in Request.Form.AllKeys
             from value in Request.Form.GetValues(name)
-            select new KeyValuePair<string, string>(name, value) :
+            select KeyValuePair.Create(name, value) :
             from name in Request.QueryString.AllKeys
             from value in Request.QueryString.GetValues(name)
-            select new KeyValuePair<string, string>(name, value))
+            select KeyValuePair.Create(name, value))
         {
             <input type="hidden" name="@parameter.Key" value="@parameter.Value" />
         }

sandbox/OpenIddict.Sandbox.AspNet.Server/Views/Authorization/EndSession.cshtml

@@ -12,10 +12,10 @@
         foreach (var parameter in string.Equals(Request.HttpMethod, "POST", StringComparison.OrdinalIgnoreCase) ?
             from name in Request.Form.AllKeys
             from value in Request.Form.GetValues(name)
-            select new KeyValuePair<string, string>(name, value) :
+            select KeyValuePair.Create(name, value) :
             from name in Request.QueryString.AllKeys
             from value in Request.QueryString.GetValues(name)
-            select new KeyValuePair<string, string>(name, value))
+            select KeyValuePair.Create(name, value))
         {
             <input type="hidden" name="@parameter.Key" value="@parameter.Value" />
         }

shared/OpenIddict.Extensions/OpenIddictHelpers.cs

@@ -1193,7 +1193,7 @@ internal static class OpenIddictHelpers
             ReadNextPairImpl();
             if (ReadSucceeded())
             {
-                return new KeyValuePair<string, string>(_currentKey, _currentValue);
+                return KeyValuePair.Create(_currentKey, _currentValue);
             }
             return null;
         }
@@ -1220,7 +1220,7 @@ internal static class OpenIddictHelpers
             await ReadNextPairAsyncImpl(cancellationToken);
             if (ReadSucceeded())
             {
-                return new KeyValuePair<string, string>(_currentKey, _currentValue);
+                return KeyValuePair.Create(_currentKey, _currentValue);
             }
             return null;
         }

shared/OpenIddict.Extensions/OpenIddictPolyfills.cs

@@ -258,16 +258,6 @@ internal static class OpenIddictPolyfills
 #endif
     }
 
-    extension(ValueTask)
-    {
-#if !SUPPORTS_VALUETASK_COMPLETED_TASK
-        /// <summary>
-        /// Gets a task that has already completed successfully.
-        /// </summary>
-        public static ValueTask CompletedTask => default;
-#endif
-    }
-
     extension<TResult>(ValueTask<TResult>)
     {
 #if !SUPPORTS_VALUETASK_COMPLETED_TASK

src/OpenIddict.Abstractions/Primitives/OpenIddictMessage.cs

@@ -152,6 +152,37 @@ public class OpenIddictMessage
     /// </summary>
     /// <param name="parameters">The message parameters.</param>
     /// <remarks>Parameters with a null or empty key are always ignored.</remarks>
+    public OpenIddictMessage(IEnumerable<KeyValuePair<string, ImmutableArray<string?>>> parameters)
+    {
+        ArgumentNullException.ThrowIfNull(parameters);
+
+        foreach (var parameter in parameters)
+        {
+            // Ignore parameters whose name is null or empty.
+            if (string.IsNullOrEmpty(parameter.Key))
+            {
+                continue;
+            }
+
+            // Note: the core OAuth 2.0 specification requires that request parameters
+            // not be present more than once but derived specifications like the
+            // token exchange specification deliberately allow specifying multiple
+            // parameters with the same name to represent a multi-valued parameter.
+            AddParameter(parameter.Key, parameter.Value switch
+            {
+                { IsDefaultOrEmpty: true } => default,
+                      [string value]       => new OpenIddictParameter(value),
+                       [..] values         => new OpenIddictParameter(values)
+            });
+        }
+    }
+
+    /// <summary>
+    /// Initializes a new OpenIddict message.
+    /// </summary>
+    /// <param name="parameters">The message parameters.</param>
+    /// <remarks>Parameters with a null or empty key are always ignored.</remarks>
+    [Obsolete("This constructor is obsolete and will be removed in a future version.")]
     public OpenIddictMessage(IEnumerable<KeyValuePair<string, ImmutableArray<string?>?>> parameters)
     {
         ArgumentNullException.ThrowIfNull(parameters);
@@ -170,7 +201,7 @@ public class OpenIddictMessage
             // parameters with the same name to represent a multi-valued parameter.
             AddParameter(parameter.Key, parameter.Value switch
             {
-                  null or []   => default,
+                  null or { IsDefaultOrEmpty: true } => default,
                           [string value]             => new OpenIddictParameter(value),
                            [..] values               => new OpenIddictParameter(values)
             });

src/OpenIddict.Abstractions/Primitives/OpenIddictRequest.cs

@@ -80,6 +80,17 @@ public class OpenIddictRequest : OpenIddictMessage
     /// </summary>
     /// <param name="parameters">The request parameters.</param>
     /// <remarks>Parameters with a null or empty key are always ignored.</remarks>
+    public OpenIddictRequest(IEnumerable<KeyValuePair<string, ImmutableArray<string?>>> parameters)
+        : base(parameters)
+    {
+    }
+
+    /// <summary>
+    /// Initializes a new OpenIddict request.
+    /// </summary>
+    /// <param name="parameters">The request parameters.</param>
+    /// <remarks>Parameters with a null or empty key are always ignored.</remarks>
+    [Obsolete("This constructor is obsolete and will be removed in a future version.")]
     public OpenIddictRequest(IEnumerable<KeyValuePair<string, ImmutableArray<string?>?>> parameters)
         : base(parameters)
     {

src/OpenIddict.Abstractions/Primitives/OpenIddictResponse.cs

@@ -79,6 +79,17 @@ public class OpenIddictResponse : OpenIddictMessage
     /// </summary>
     /// <param name="parameters">The response parameters.</param>
     /// <remarks>Parameters with a null or empty key are always ignored.</remarks>
+    public OpenIddictResponse(IEnumerable<KeyValuePair<string, ImmutableArray<string?>>> parameters)
+        : base(parameters)
+    {
+    }
+
+    /// <summary>
+    /// Initializes a new OpenIddict response.
+    /// </summary>
+    /// <param name="parameters">The response parameters.</param>
+    /// <remarks>Parameters with a null or empty key are always ignored.</remarks>
+    [Obsolete("This constructor is obsolete and will be removed in a future version.")]
     public OpenIddictResponse(IEnumerable<KeyValuePair<string, ImmutableArray<string?>?>> parameters)
         : base(parameters)
     {

src/OpenIddict.Client.Owin/OpenIddictClientOwinHandlers.cs

@@ -245,7 +245,7 @@ public static partial class OpenIddictClientOwinHandlers
                 context.Transaction.Request = new OpenIddictRequest(
                     from parameter in request.Query
                     let values = new StringValues(parameter.Value)
-                    select new KeyValuePair<string, StringValues>(parameter.Key, values));
+                    select KeyValuePair.Create(parameter.Key, values));
             }
 
             else if (string.Equals(request.Method, "POST", StringComparison.OrdinalIgnoreCase))
@@ -279,7 +279,7 @@ public static partial class OpenIddictClientOwinHandlers
                 context.Transaction.Request = new OpenIddictRequest(
                     from parameter in await request.ReadFormAsync()
                     let values = new StringValues(parameter.Value)
-                    select new KeyValuePair<string, StringValues>(parameter.Key, values));
+                    select KeyValuePair.Create(parameter.Key, values));
             }
 
             else

src/OpenIddict.Client.SystemNetHttp/OpenIddictClientSystemNetHttpHandlers.cs

@@ -1148,7 +1148,7 @@ public static partial class OpenIddictClientSystemNetHttpHandlers
                     let values = (ImmutableArray<string?>?) parameter.Value
                     where values is not null
                     from value in values.GetValueOrDefault()
-                    select new KeyValuePair<string?, string?>(parameter.Key, value));
+                    select KeyValuePair.Create(parameter.Key, value));
             }
 
             return ValueTask.CompletedTask;
@@ -1590,7 +1590,7 @@ public static partial class OpenIddictClientSystemNetHttpHandlers
                         value = parameter[start..index].Trim();
                     }
 
-                    yield return new KeyValuePair<string, string?>(key, value);
+                    yield return KeyValuePair.Create<string, string?>(key, value);
                 }
             }
         }

src/OpenIddict.Server.Owin/OpenIddictServerOwinHandlers.cs

@@ -493,7 +493,7 @@ public static partial class OpenIddictServerOwinHandlers
                 context.Transaction.Request = new OpenIddictRequest(
                     from parameter in request.Query
                     let values = new StringValues(parameter.Value)
-                    select new KeyValuePair<string, StringValues>(parameter.Key, values));
+                    select KeyValuePair.Create(parameter.Key, values));
             }
 
             else
@@ -544,7 +544,7 @@ public static partial class OpenIddictServerOwinHandlers
                 context.Transaction.Request = new OpenIddictRequest(
                     from parameter in request.Query
                     let values = new StringValues(parameter.Value)
-                    select new KeyValuePair<string, StringValues>(parameter.Key, values));
+                    select KeyValuePair.Create(parameter.Key, values));
             }
 
             else if (string.Equals(request.Method, "POST", StringComparison.OrdinalIgnoreCase))
@@ -578,7 +578,7 @@ public static partial class OpenIddictServerOwinHandlers
                 context.Transaction.Request = new OpenIddictRequest(
                     from parameter in await request.ReadFormAsync()
                     let values = new StringValues(parameter.Value)
-                    select new KeyValuePair<string, StringValues>(parameter.Key, values));
+                    select KeyValuePair.Create(parameter.Key, values));
             }
 
             else
@@ -653,7 +653,7 @@ public static partial class OpenIddictServerOwinHandlers
                 context.Transaction.Request = new OpenIddictRequest(
                     from parameter in await request.ReadFormAsync()
                     let values = new StringValues(parameter.Value)
-                    select new KeyValuePair<string, StringValues>(parameter.Key, values));
+                    select KeyValuePair.Create(parameter.Key, values));
             }
 
             else

src/OpenIddict.Validation.SystemNetHttp/OpenIddictValidationSystemNetHttpHandlers.cs

@@ -548,7 +548,7 @@ public static partial class OpenIddictValidationSystemNetHttpHandlers
                     let values = (ImmutableArray<string?>?) parameter.Value
                     where values is not null
                     from value in values.GetValueOrDefault()
-                    select new KeyValuePair<string?, string?>(parameter.Key, value));
+                    select KeyValuePair.Create(parameter.Key, value));
             }
 
             return ValueTask.CompletedTask;
@@ -990,7 +990,7 @@ public static partial class OpenIddictValidationSystemNetHttpHandlers
                         value = parameter[start..index].Trim();
                     }
 
-                    yield return new KeyValuePair<string, string?>(key, value);
+                    yield return KeyValuePair.Create<string, string?>(key, value);
                 }
             }
         }

test/OpenIddict.Abstractions.Tests/Primitives/OpenIddictMessageTests.cs

@@ -36,8 +36,8 @@ public class OpenIddictMessageTests
         {
             return new OpenIddictMessage(
             [
-                new KeyValuePair<string, OpenIddictParameter>("parameter", "Fabrikam"),
-                new KeyValuePair<string, OpenIddictParameter>("parameter", "Contoso")
+                KeyValuePair.Create("parameter", new OpenIddictParameter("Fabrikam")),
+                KeyValuePair.Create("parameter", new OpenIddictParameter("Contoso"))
             ]);
         });
 
@@ -51,7 +51,7 @@ public class OpenIddictMessageTests
         // Arrange and act
         var message = new OpenIddictMessage(
         [
-            new KeyValuePair<string, OpenIddictParameter>("parameter", 42)
+            KeyValuePair.Create("parameter", new OpenIddictParameter(42))
         ]);
 
         // Assert
@@ -66,7 +66,7 @@ public class OpenIddictMessageTests
         // Arrange and act
         var message = new OpenIddictMessage(
         [
-            new KeyValuePair<string, OpenIddictParameter>(name!, "Fabrikam")
+            KeyValuePair.Create(name!, new OpenIddictParameter("Fabrikam"))
         ]);
 
         // Assert
@@ -79,8 +79,8 @@ public class OpenIddictMessageTests
         // Arrange and act
         var message = new OpenIddictMessage(
         [
-            new KeyValuePair<string, OpenIddictParameter>("null-parameter", (string?) null),
-            new KeyValuePair<string, OpenIddictParameter>("empty-parameter", string.Empty)
+            KeyValuePair.Create("null-parameter", new OpenIddictParameter((string?) null)),
+            KeyValuePair.Create("empty-parameter", new OpenIddictParameter(string.Empty))
         ]);
 
         // Assert
@@ -93,8 +93,8 @@ public class OpenIddictMessageTests
         // Arrange and act
         var message = new OpenIddictMessage(
         [
-            new KeyValuePair<string, string?>("parameter", "Fabrikam"),
-            new KeyValuePair<string, string?>("parameter", "Contoso")
+            KeyValuePair.Create<string, string?>("parameter", "Fabrikam"),
+            KeyValuePair.Create<string, string?>("parameter", "Contoso")
         ]);
 
         // Assert
@@ -109,7 +109,7 @@ public class OpenIddictMessageTests
         // Arrange and act
         var message = new OpenIddictMessage(
         [
-            new KeyValuePair<string, ImmutableArray<string?>?>("parameter", ["Fabrikam", "Contoso"])
+            KeyValuePair.Create<string, ImmutableArray<string?>>("parameter", ["Fabrikam", "Contoso"])
         ]);
 
         // Assert
@@ -124,7 +124,7 @@ public class OpenIddictMessageTests
         // Arrange and act
         var message = new OpenIddictMessage(
         [
-            new KeyValuePair<string, ImmutableArray<string?>?>("parameter", ["Fabrikam"])
+            KeyValuePair.Create<string, ImmutableArray<string?>>("parameter", ["Fabrikam"])
         ]);
 
         // Assert

test/OpenIddict.Server.AspNetCore.IntegrationTests/OpenIddictServerAspNetCoreIntegrationTests.cs

@@ -823,8 +823,7 @@ public partial class OpenIddictServerAspNetCoreIntegrationTests : OpenIddictServ
                     }
 
                     var claims = result.Principal.Claims.GroupBy(claim => claim.Type)
-                        .Select(group => new KeyValuePair<string, ImmutableArray<string?>?>(
-                            group.Key, group.Select(claim => claim.Value).ToImmutableArray<string?>()));
+                        .Select(group => KeyValuePair.Create(group.Key, group.Select(claim => claim.Value).ToImmutableArray<string?>()));
 
                     context.Response.ContentType = "application/json";
                     await context.Response.WriteAsync(JsonSerializer.Serialize(new OpenIddictResponse(claims)));

test/OpenIddict.Server.IntegrationTests/OpenIddictServerIntegrationTestClient.cs

@@ -204,7 +204,7 @@ public class OpenIddictServerIntegrationTestClient : IAsyncDisposable
                 let values = (ImmutableArray<string?>?) parameter.Value
                 where values is not null
                 from value in values.GetValueOrDefault()
-                select new KeyValuePair<string?, string?>(parameter.Key, value));
+                select KeyValuePair.Create(parameter.Key, value));
         }
 
         return message;
@@ -295,7 +295,7 @@ public class OpenIddictServerIntegrationTestClient : IAsyncDisposable
                         value = parameter[start..index].Trim();
                     }
 
-                    yield return new KeyValuePair<string, string?>(key, value);
+                    yield return KeyValuePair.Create<string, string?>(key, value);
                 }
             }
         }
@@ -356,14 +356,14 @@ public class OpenIddictServerIntegrationTestClient : IAsyncDisposable
 
                 var value = UnescapeDataString(segment.Substring(index + 1, segment.Length - (index + 1)));
 
-                parameters.Add(new KeyValuePair<string, string?>(name, value));
+                parameters.Add(KeyValuePair.Create(name, value));
             }
 
             return new OpenIddictResponse(
                 from parameter in parameters
                 group parameter by parameter.Key into grouping
                 let values = grouping.Select(parameter => parameter.Value)
-                select new KeyValuePair<string, StringValues>(grouping.Key, values.ToArray()));
+                select KeyValuePair.Create(grouping.Key, new StringValues(values.ToArray())));
         }
 
         else if (string.Equals(message.Content?.Headers?.ContentType?.MediaType, "application/json", StringComparison.OrdinalIgnoreCase))
@@ -399,14 +399,14 @@ public class OpenIddictServerIntegrationTestClient : IAsyncDisposable
 
                 var value = element.GetAttribute("value");
 
-                parameters.Add(new KeyValuePair<string, string?>(name, value));
+                parameters.Add(KeyValuePair.Create(name, value));
             }
 
             return new OpenIddictResponse(
                 from parameter in parameters
                 group parameter by parameter.Key into grouping
                 let values = grouping.Select(parameter => parameter.Value)
-                select new KeyValuePair<string, StringValues>(grouping.Key, values.ToArray()));
+                select KeyValuePair.Create(grouping.Key, new StringValues(values.ToArray())));
         }
 
         else if (string.Equals(message.Content?.Headers?.ContentType?.MediaType, "text/plain", StringComparison.OrdinalIgnoreCase))
@@ -438,14 +438,14 @@ public class OpenIddictServerIntegrationTestClient : IAsyncDisposable
 
                 var value = line[(index + 1)..];
 
-                parameters.Add(new KeyValuePair<string, string>(name, value));
+                parameters.Add(KeyValuePair.Create(name, value));
             }
 
             return new OpenIddictResponse(
                 from parameter in parameters
                 group parameter by parameter.Key into grouping
                 let values = grouping.Select(parameter => parameter.Value)
-                select new KeyValuePair<string, StringValues>(grouping.Key, values.ToArray()));
+                select KeyValuePair.Create(grouping.Key, new StringValues(values.ToArray())));
         }
 
         return new OpenIddictResponse();

test/OpenIddict.Server.Owin.IntegrationTests/OpenIddictServerOwinIntegrationTests.cs

@@ -776,8 +776,7 @@ public partial class OpenIddictServerOwinIntegrationTests : OpenIddictServerInte
                     }
 
                     var claims = result.Identity.Claims.GroupBy(claim => claim.Type)
-                        .Select(group => new KeyValuePair<string, ImmutableArray<string?>?>(
-                            group.Key, group.Select(claim => claim.Value).ToImmutableArray<string?>()));
+                        .Select(group => KeyValuePair.Create(group.Key, group.Select(claim => claim.Value).ToImmutableArray<string?>()));
 
                     context.Response.ContentType = "application/json";
                     await context.Response.WriteAsync(JsonSerializer.Serialize(new OpenIddictResponse(claims)));

test/OpenIddict.Validation.AspNetCore.IntegrationTests/OpenIddictValidationAspNetCoreIntegrationTests.cs

@@ -185,8 +185,7 @@ public partial class OpenIddictValidationAspNetCoreIntegrationTests : OpenIddict
                     }
 
                     var claims = result.Principal.Claims.GroupBy(claim => claim.Type)
-                        .Select(group => new KeyValuePair<string, ImmutableArray<string?>?>(
-                            group.Key, group.Select(claim => claim.Value).ToImmutableArray<string?>()));
+                        .Select(group => KeyValuePair.Create(group.Key, group.Select(claim => claim.Value).ToImmutableArray<string?>()));
 
                     context.Response.ContentType = "application/json";
                     await context.Response.WriteAsync(JsonSerializer.Serialize(new OpenIddictResponse(claims)));

test/OpenIddict.Validation.IntegrationTests/OpenIddictValidationIntegrationTestClient.cs

@@ -204,7 +204,7 @@ public class OpenIddictValidationIntegrationTestClient : IAsyncDisposable
                 let values = (ImmutableArray<string?>?) parameter.Value
                 where values is not null
                 from value in values.GetValueOrDefault()
-                select new KeyValuePair<string?, string?>(parameter.Key, value));
+                select KeyValuePair.Create(parameter.Key, value));
         }
 
         return message;
@@ -295,7 +295,7 @@ public class OpenIddictValidationIntegrationTestClient : IAsyncDisposable
                         value = parameter[start..index].Trim();
                     }
 
-                    yield return new KeyValuePair<string, string?>(key, value);
+                    yield return KeyValuePair.Create<string, string?>(key, value);
                 }
             }
         }
@@ -356,14 +356,14 @@ public class OpenIddictValidationIntegrationTestClient : IAsyncDisposable
 
                 var value = UnescapeDataString(segment.Substring(index + 1, segment.Length - (index + 1)));
 
-                parameters.Add(new KeyValuePair<string, string?>(name, value));
+                parameters.Add(KeyValuePair.Create(name, value));
             }
 
             return new OpenIddictResponse(
                 from parameter in parameters
                 group parameter by parameter.Key into grouping
                 let values = grouping.Select(parameter => parameter.Value)
-                select new KeyValuePair<string, StringValues>(grouping.Key, values.ToArray()));
+                select KeyValuePair.Create(grouping.Key, new StringValues(values.ToArray())));
         }
 
         else if (string.Equals(message.Content?.Headers?.ContentType?.MediaType, "application/json", StringComparison.OrdinalIgnoreCase))
@@ -399,14 +399,14 @@ public class OpenIddictValidationIntegrationTestClient : IAsyncDisposable
 
                 var value = element.GetAttribute("value");
 
-                parameters.Add(new KeyValuePair<string, string?>(name, value));
+                parameters.Add(KeyValuePair.Create(name, value));
             }
 
             return new OpenIddictResponse(
                 from parameter in parameters
                 group parameter by parameter.Key into grouping
                 let values = grouping.Select(parameter => parameter.Value)
-                select new KeyValuePair<string, StringValues>(grouping.Key, values.ToArray()));
+                select KeyValuePair.Create(grouping.Key, new StringValues(values.ToArray())));
         }
 
         else if (string.Equals(message.Content?.Headers?.ContentType?.MediaType, "text/plain", StringComparison.OrdinalIgnoreCase))
@@ -438,14 +438,14 @@ public class OpenIddictValidationIntegrationTestClient : IAsyncDisposable
 
                 var value = line[(index + 1)..];
 
-                parameters.Add(new KeyValuePair<string, string>(name, value));
+                parameters.Add(KeyValuePair.Create(name, value));
             }
 
             return new OpenIddictResponse(
                 from parameter in parameters
                 group parameter by parameter.Key into grouping
                 let values = grouping.Select(parameter => parameter.Value)
-                select new KeyValuePair<string, StringValues>(grouping.Key, values.ToArray()));
+                select KeyValuePair.Create(grouping.Key, new StringValues(values.ToArray())));
         }
 
         return new OpenIddictResponse();

test/OpenIddict.Validation.Owin.IntegrationTests/OpenIddictValidationOwinIntegrationTests.cs

@@ -170,8 +170,7 @@ public partial class OpenIddictValidationOwinIntegrationTests : OpenIddictValida
                     }
 
                     var claims = result.Identity.Claims.GroupBy(claim => claim.Type)
-                        .Select(group => new KeyValuePair<string, ImmutableArray<string?>?>(
-                            group.Key, group.Select(claim => claim.Value).ToImmutableArray<string?>()));
+                        .Select(group => KeyValuePair.Create(group.Key, group.Select(claim => claim.Value).ToImmutableArray<string?>()));
 
                     context.Response.ContentType = "application/json";
                     await context.Response.WriteAsync(JsonSerializer.Serialize(new OpenIddictResponse(claims)));