From 98e94cbb35c47c51eb40724a99c5231b79f4e6fd Mon Sep 17 00:00:00 2001
From: Austin Drummond <adrum0x7@gmail.com>
Date: Fri, 19 Sep 2025 13:09:58 -0400
Subject: [PATCH 1/7] added Back helper function

---
 InertiaCore/Inertia.cs           |   2 +
 InertiaCore/ResponseFactory.cs   |   2 +
 InertiaCore/Utils/BackResult.cs  |  27 +++++
 InertiaCoreTests/UnitTestBack.cs | 197 +++++++++++++++++++++++++++++++
 4 files changed, 228 insertions(+)
 create mode 100644 InertiaCore/Utils/BackResult.cs
 create mode 100644 InertiaCoreTests/UnitTestBack.cs

diff --git a/InertiaCore/Inertia.cs b/InertiaCore/Inertia.cs
index d13b932..edd07ff 100644
--- a/InertiaCore/Inertia.cs
+++ b/InertiaCore/Inertia.cs
@@ -27,6 +27,8 @@ public static class Inertia
 
     public static LocationResult Location(string url) => _factory.Location(url);
 
+    public static BackResult Back(string? fallbackUrl = null) => _factory.Back(fallbackUrl);
+
     public static void Share(string key, object? value) => _factory.Share(key, value);
 
     public static void Share(IDictionary<string, object?> data) => _factory.Share(data);
diff --git a/InertiaCore/ResponseFactory.cs b/InertiaCore/ResponseFactory.cs
index ad57af9..2b0244f 100644
--- a/InertiaCore/ResponseFactory.cs
+++ b/InertiaCore/ResponseFactory.cs
@@ -20,6 +20,7 @@ internal interface IResponseFactory
     public void Version(Func<string?> version);
     public string? GetVersion();
     public LocationResult Location(string url);
+    public BackResult Back(string? fallbackUrl = null);
     public void Share(string key, object? value);
     public void Share(IDictionary<string, object?> data);
     public AlwaysProp Always(object? value);
@@ -108,6 +109,7 @@ public async Task<IHtmlContent> Html(dynamic model)
     };
 
     public LocationResult Location(string url) => new(url);
+    public BackResult Back(string? fallbackUrl = null) => new(fallbackUrl);
 
     public void Share(string key, object? value)
     {
diff --git a/InertiaCore/Utils/BackResult.cs b/InertiaCore/Utils/BackResult.cs
new file mode 100644
index 0000000..71baf7e
--- /dev/null
+++ b/InertiaCore/Utils/BackResult.cs
@@ -0,0 +1,27 @@
+using System.Net;
+using InertiaCore.Extensions;
+using Microsoft.AspNetCore.Mvc;
+
+namespace InertiaCore.Utils;
+
+public class BackResult : IActionResult
+{
+    private readonly string _fallbackUrl;
+
+    public BackResult(string? fallbackUrl = null) => _fallbackUrl = fallbackUrl ?? "/";
+
+    public async Task ExecuteResultAsync(ActionContext context)
+    {
+        var referrer = context.HttpContext.Request.Headers.Referer.ToString();
+        var redirectUrl = !string.IsNullOrEmpty(referrer) ? referrer : _fallbackUrl;
+
+        if (context.IsInertiaRequest())
+        {
+            context.HttpContext.Response.Headers.Override(InertiaHeader.Location, redirectUrl);
+            await new StatusCodeResult((int)HttpStatusCode.Conflict).ExecuteResultAsync(context);
+            return;
+        }
+
+        await new RedirectResult(redirectUrl).ExecuteResultAsync(context);
+    }
+}
diff --git a/InertiaCoreTests/UnitTestBack.cs b/InertiaCoreTests/UnitTestBack.cs
new file mode 100644
index 0000000..ffdf3d6
--- /dev/null
+++ b/InertiaCoreTests/UnitTestBack.cs
@@ -0,0 +1,197 @@
+using System.Net;
+using InertiaCore;
+using InertiaCore.Extensions;
+using InertiaCore.Utils;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Abstractions;
+using Microsoft.AspNetCore.Mvc.Infrastructure;
+using Microsoft.AspNetCore.Routing;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
+using Moq;
+
+namespace InertiaCoreTests;
+
+public partial class Tests
+{
+    [Test]
+    [Description("Test Back function with Inertia request returns conflict status with location header.")]
+    public async Task TestBackWithInertiaRequest()
+    {
+        var backResult = _factory.Back("/fallback");
+
+        var headers = new HeaderDictionary
+        {
+            { "X-Inertia", "true" }
+        };
+
+        var responseHeaders = new HeaderDictionary();
+        var response = new Mock<HttpResponse>();
+        response.SetupGet(r => r.Headers).Returns(responseHeaders);
+        response.SetupGet(r => r.StatusCode).Returns(0);
+        response.SetupSet(r => r.StatusCode = It.IsAny<int>());
+
+        var request = new Mock<HttpRequest>();
+        request.SetupGet(r => r.Headers).Returns(headers);
+
+        // Set up service provider
+        var services = new ServiceCollection();
+        services.AddSingleton<IActionResultExecutor<StatusCodeResult>>(new Mock<IActionResultExecutor<StatusCodeResult>>().Object);
+        services.AddLogging();
+        var serviceProvider = services.BuildServiceProvider();
+
+        var httpContext = new Mock<HttpContext>();
+        httpContext.SetupGet(c => c.Request).Returns(request.Object);
+        httpContext.SetupGet(c => c.Response).Returns(response.Object);
+        httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
+
+        var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
+
+        await backResult.ExecuteResultAsync(context);
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(responseHeaders.ContainsKey("X-Inertia-Location"), Is.True);
+            Assert.That(responseHeaders["X-Inertia-Location"].ToString(), Is.EqualTo("back"));
+            // Verify that status code 409 (Conflict) is set
+            response.VerifySet(r => r.StatusCode = (int)HttpStatusCode.Conflict, Times.Once);
+        });
+    }
+
+    [Test]
+    [Description("Test Back function with regular request and referrer header redirects to referrer.")]
+    public async Task TestBackWithReferrerHeader()
+    {
+        var backResult = _factory.Back("/fallback");
+
+        var headers = new HeaderDictionary
+        {
+            { "Referer", "https://example.com/previous-page" }
+        };
+
+        var responseHeaders = new HeaderDictionary();
+        string? redirectLocation = null;
+        var response = new Mock<HttpResponse>();
+        response.SetupGet(r => r.Headers).Returns(responseHeaders);
+        response.SetupGet(r => r.StatusCode).Returns(0);
+        response.SetupSet(r => r.StatusCode = It.IsAny<int>());
+        response.Setup(r => r.Redirect(It.IsAny<string>()))
+            .Callback<string>(location => redirectLocation = location);
+
+        var request = new Mock<HttpRequest>();
+        request.SetupGet(r => r.Headers).Returns(headers);
+        request.SetupGet(r => r.Scheme).Returns("https");
+        request.SetupGet(r => r.Host).Returns(new HostString("example.com"));
+
+        // Set up service provider
+        var services = new ServiceCollection();
+        services.AddSingleton<IActionResultExecutor<RedirectResult>>(new Mock<IActionResultExecutor<RedirectResult>>().Object);
+        services.AddSingleton<ILoggerFactory>(new Mock<ILoggerFactory>().Object);
+        var serviceProvider = services.BuildServiceProvider();
+
+        var httpContext = new Mock<HttpContext>();
+        httpContext.SetupGet(c => c.Request).Returns(request.Object);
+        httpContext.SetupGet(c => c.Response).Returns(response.Object);
+        httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
+
+        var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
+
+        var result = backResult as IActionResult;
+        Assert.That(result, Is.Not.Null);
+
+        await result.ExecuteResultAsync(context);
+
+        // The BackResult should use the referrer URL since the request is not an Inertia request
+        Assert.Pass("Back function correctly handled referrer redirect");
+    }
+
+    [Test]
+    [Description("Test Back function without referrer uses fallback URL.")]
+    public async Task TestBackWithFallbackUrl()
+    {
+        var backResult = _factory.Back("/custom-fallback");
+
+        var headers = new HeaderDictionary();
+
+        var responseHeaders = new HeaderDictionary();
+        string? redirectLocation = null;
+        var response = new Mock<HttpResponse>();
+        response.SetupGet(r => r.Headers).Returns(responseHeaders);
+        response.SetupGet(r => r.StatusCode).Returns(0);
+        response.SetupSet(r => r.StatusCode = It.IsAny<int>());
+        response.Setup(r => r.Redirect(It.IsAny<string>()))
+            .Callback<string>(location => redirectLocation = location);
+
+        var request = new Mock<HttpRequest>();
+        request.SetupGet(r => r.Headers).Returns(headers);
+        request.SetupGet(r => r.Scheme).Returns("https");
+        request.SetupGet(r => r.Host).Returns(new HostString("example.com"));
+
+        // Set up service provider
+        var services = new ServiceCollection();
+        services.AddSingleton<IActionResultExecutor<RedirectResult>>(new Mock<IActionResultExecutor<RedirectResult>>().Object);
+        services.AddSingleton<ILoggerFactory>(new Mock<ILoggerFactory>().Object);
+        var serviceProvider = services.BuildServiceProvider();
+
+        var httpContext = new Mock<HttpContext>();
+        httpContext.SetupGet(c => c.Request).Returns(request.Object);
+        httpContext.SetupGet(c => c.Response).Returns(response.Object);
+        httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
+
+        var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
+
+        var result = backResult as IActionResult;
+        Assert.That(result, Is.Not.Null);
+
+        await result.ExecuteResultAsync(context);
+
+        // The BackResult should use the fallback URL since there is no referrer
+        Assert.Pass("Back function correctly used fallback URL");
+    }
+
+    [Test]
+    [Description("Test Back function without fallback URL uses default root path.")]
+    public async Task TestBackWithDefaultFallback()
+    {
+        var backResult = _factory.Back();
+
+        var headers = new HeaderDictionary();
+
+        var responseHeaders = new HeaderDictionary();
+        string? redirectLocation = null;
+        var response = new Mock<HttpResponse>();
+        response.SetupGet(r => r.Headers).Returns(responseHeaders);
+        response.SetupGet(r => r.StatusCode).Returns(0);
+        response.SetupSet(r => r.StatusCode = It.IsAny<int>());
+        response.Setup(r => r.Redirect(It.IsAny<string>()))
+            .Callback<string>(location => redirectLocation = location);
+
+        var request = new Mock<HttpRequest>();
+        request.SetupGet(r => r.Headers).Returns(headers);
+        request.SetupGet(r => r.Scheme).Returns("https");
+        request.SetupGet(r => r.Host).Returns(new HostString("example.com"));
+
+        // Set up service provider
+        var services = new ServiceCollection();
+        services.AddSingleton<IActionResultExecutor<RedirectResult>>(new Mock<IActionResultExecutor<RedirectResult>>().Object);
+        services.AddSingleton<ILoggerFactory>(new Mock<ILoggerFactory>().Object);
+        var serviceProvider = services.BuildServiceProvider();
+
+        var httpContext = new Mock<HttpContext>();
+        httpContext.SetupGet(c => c.Request).Returns(request.Object);
+        httpContext.SetupGet(c => c.Response).Returns(response.Object);
+        httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
+
+        var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
+
+        var result = backResult as IActionResult;
+        Assert.That(result, Is.Not.Null);
+
+        await result.ExecuteResultAsync(context);
+
+        // The BackResult should use the default "/" URL since there is no referrer and no fallback provided
+        Assert.Pass("Back function correctly used default fallback");
+    }
+
+}
\ No newline at end of file

From 6056d078cdde25234ce2e383a0aa7d0bc8c6b0fc Mon Sep 17 00:00:00 2001
From: Austin Drummond <adrum0x7@gmail.com>
Date: Fri, 19 Sep 2025 13:50:25 -0400
Subject: [PATCH 2/7] always use 302

---
 InertiaCore/Utils/BackResult.cs | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/InertiaCore/Utils/BackResult.cs b/InertiaCore/Utils/BackResult.cs
index 71baf7e..fdc422d 100644
--- a/InertiaCore/Utils/BackResult.cs
+++ b/InertiaCore/Utils/BackResult.cs
@@ -15,13 +15,6 @@ public async Task ExecuteResultAsync(ActionContext context)
         var referrer = context.HttpContext.Request.Headers.Referer.ToString();
         var redirectUrl = !string.IsNullOrEmpty(referrer) ? referrer : _fallbackUrl;
 
-        if (context.IsInertiaRequest())
-        {
-            context.HttpContext.Response.Headers.Override(InertiaHeader.Location, redirectUrl);
-            await new StatusCodeResult((int)HttpStatusCode.Conflict).ExecuteResultAsync(context);
-            return;
-        }
-
         await new RedirectResult(redirectUrl).ExecuteResultAsync(context);
     }
 }

From 45a35f8e9bb52b7247490e2beea05666e7e216b3 Mon Sep 17 00:00:00 2001
From: Austin Drummond <adrum0x7@gmail.com>
Date: Fri, 19 Sep 2025 13:52:29 -0400
Subject: [PATCH 3/7] update tests

---
 InertiaCoreTests/UnitTestBack.cs | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/InertiaCoreTests/UnitTestBack.cs b/InertiaCoreTests/UnitTestBack.cs
index ffdf3d6..040ccaf 100644
--- a/InertiaCoreTests/UnitTestBack.cs
+++ b/InertiaCoreTests/UnitTestBack.cs
@@ -16,7 +16,7 @@ namespace InertiaCoreTests;
 public partial class Tests
 {
     [Test]
-    [Description("Test Back function with Inertia request returns conflict status with location header.")]
+    [Description("Test Back function with Inertia request returns redirect status with location header.")]
     public async Task TestBackWithInertiaRequest()
     {
         var backResult = _factory.Back("/fallback");
@@ -52,10 +52,10 @@ public async Task TestBackWithInertiaRequest()
 
         Assert.Multiple(() =>
         {
-            Assert.That(responseHeaders.ContainsKey("X-Inertia-Location"), Is.True);
-            Assert.That(responseHeaders["X-Inertia-Location"].ToString(), Is.EqualTo("back"));
-            // Verify that status code 409 (Conflict) is set
-            response.VerifySet(r => r.StatusCode = (int)HttpStatusCode.Conflict, Times.Once);
+            Assert.That(responseHeaders.ContainsKey("Location"), Is.True);
+            Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("back"));
+            // Verify that status code 302 (Redirect) is set
+            response.VerifySet(r => r.StatusCode = (int)HttpStatusCode.Redirect, Times.Once);
         });
     }
 
@@ -194,4 +194,4 @@ public async Task TestBackWithDefaultFallback()
         Assert.Pass("Back function correctly used default fallback");
     }
 
-}
\ No newline at end of file
+}

From 70240c7508d752de6874859f5ec5cd21960e2a33 Mon Sep 17 00:00:00 2001
From: Austin Drummond <adrum0x7@gmail.com>
Date: Fri, 19 Sep 2025 17:30:12 -0400
Subject: [PATCH 4/7] fix tests

---
 InertiaCoreTests/UnitTestBack.cs | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/InertiaCoreTests/UnitTestBack.cs b/InertiaCoreTests/UnitTestBack.cs
index 040ccaf..876c70c 100644
--- a/InertiaCoreTests/UnitTestBack.cs
+++ b/InertiaCoreTests/UnitTestBack.cs
@@ -1,8 +1,10 @@
+using System.Collections.Generic;
 using System.Net;
 using InertiaCore;
 using InertiaCore.Extensions;
 using InertiaCore.Utils;
 using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.Abstractions;
 using Microsoft.AspNetCore.Mvc.Infrastructure;
@@ -39,24 +41,22 @@ public async Task TestBackWithInertiaRequest()
         var services = new ServiceCollection();
         services.AddSingleton<IActionResultExecutor<StatusCodeResult>>(new Mock<IActionResultExecutor<StatusCodeResult>>().Object);
         services.AddLogging();
+        services.AddMvc();
         var serviceProvider = services.BuildServiceProvider();
 
         var httpContext = new Mock<HttpContext>();
         httpContext.SetupGet(c => c.Request).Returns(request.Object);
         httpContext.SetupGet(c => c.Response).Returns(response.Object);
         httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
+        httpContext.SetupGet(c => c.Items).Returns(new Dictionary<object, object?>());
+        httpContext.SetupGet(c => c.Features).Returns(new FeatureCollection());
 
         var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
 
         await backResult.ExecuteResultAsync(context);
 
-        Assert.Multiple(() =>
-        {
-            Assert.That(responseHeaders.ContainsKey("Location"), Is.True);
-            Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("back"));
-            // Verify that status code 302 (Redirect) is set
-            response.VerifySet(r => r.StatusCode = (int)HttpStatusCode.Redirect, Times.Once);
-        });
+        // Since there's no referrer, it should redirect to the fallback URL
+        response.Verify(r => r.Redirect("/fallback", false), Times.Once);
     }
 
     [Test]
@@ -88,12 +88,15 @@ public async Task TestBackWithReferrerHeader()
         var services = new ServiceCollection();
         services.AddSingleton<IActionResultExecutor<RedirectResult>>(new Mock<IActionResultExecutor<RedirectResult>>().Object);
         services.AddSingleton<ILoggerFactory>(new Mock<ILoggerFactory>().Object);
+        services.AddMvc();
         var serviceProvider = services.BuildServiceProvider();
 
         var httpContext = new Mock<HttpContext>();
         httpContext.SetupGet(c => c.Request).Returns(request.Object);
         httpContext.SetupGet(c => c.Response).Returns(response.Object);
         httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
+        httpContext.SetupGet(c => c.Items).Returns(new Dictionary<object, object?>());
+        httpContext.SetupGet(c => c.Features).Returns(new FeatureCollection());
 
         var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
 
@@ -132,12 +135,15 @@ public async Task TestBackWithFallbackUrl()
         var services = new ServiceCollection();
         services.AddSingleton<IActionResultExecutor<RedirectResult>>(new Mock<IActionResultExecutor<RedirectResult>>().Object);
         services.AddSingleton<ILoggerFactory>(new Mock<ILoggerFactory>().Object);
+        services.AddMvc();
         var serviceProvider = services.BuildServiceProvider();
 
         var httpContext = new Mock<HttpContext>();
         httpContext.SetupGet(c => c.Request).Returns(request.Object);
         httpContext.SetupGet(c => c.Response).Returns(response.Object);
         httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
+        httpContext.SetupGet(c => c.Items).Returns(new Dictionary<object, object?>());
+        httpContext.SetupGet(c => c.Features).Returns(new FeatureCollection());
 
         var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
 
@@ -182,6 +188,8 @@ public async Task TestBackWithDefaultFallback()
         httpContext.SetupGet(c => c.Request).Returns(request.Object);
         httpContext.SetupGet(c => c.Response).Returns(response.Object);
         httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
+        httpContext.SetupGet(c => c.Items).Returns(new Dictionary<object, object?>());
+        httpContext.SetupGet(c => c.Features).Returns(new FeatureCollection());
 
         var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
 

From 2b7caf8a3c4664780097aa8a7510331817d90527 Mon Sep 17 00:00:00 2001
From: Austin Drummond <adrum0x7@gmail.com>
Date: Fri, 19 Sep 2025 23:06:27 -0400
Subject: [PATCH 5/7] remove pass messages

---
 InertiaCoreTests/UnitTestBack.cs | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/InertiaCoreTests/UnitTestBack.cs b/InertiaCoreTests/UnitTestBack.cs
index 876c70c..4c666fe 100644
--- a/InertiaCoreTests/UnitTestBack.cs
+++ b/InertiaCoreTests/UnitTestBack.cs
@@ -104,9 +104,6 @@ public async Task TestBackWithReferrerHeader()
         Assert.That(result, Is.Not.Null);
 
         await result.ExecuteResultAsync(context);
-
-        // The BackResult should use the referrer URL since the request is not an Inertia request
-        Assert.Pass("Back function correctly handled referrer redirect");
     }
 
     [Test]
@@ -151,9 +148,6 @@ public async Task TestBackWithFallbackUrl()
         Assert.That(result, Is.Not.Null);
 
         await result.ExecuteResultAsync(context);
-
-        // The BackResult should use the fallback URL since there is no referrer
-        Assert.Pass("Back function correctly used fallback URL");
     }
 
     [Test]
@@ -197,9 +191,6 @@ public async Task TestBackWithDefaultFallback()
         Assert.That(result, Is.Not.Null);
 
         await result.ExecuteResultAsync(context);
-
-        // The BackResult should use the default "/" URL since there is no referrer and no fallback provided
-        Assert.Pass("Back function correctly used default fallback");
     }
 
 }

From e0c2689f18c622923527150c6e806a6aa58a2633 Mon Sep 17 00:00:00 2001
From: Austin Drummond <adrum0x7@gmail.com>
Date: Sun, 21 Sep 2025 18:49:34 -0400
Subject: [PATCH 6/7] change back http status to 303

---
 InertiaCore/Inertia.cs           |   5 +-
 InertiaCore/ResponseFactory.cs   |   4 +-
 InertiaCore/Utils/BackResult.cs  |  11 ++-
 InertiaCoreTests/UnitTestBack.cs | 113 ++++++++++++++-----------------
 4 files changed, 63 insertions(+), 70 deletions(-)

diff --git a/InertiaCore/Inertia.cs b/InertiaCore/Inertia.cs
index edd07ff..0676a7a 100644
--- a/InertiaCore/Inertia.cs
+++ b/InertiaCore/Inertia.cs
@@ -1,4 +1,5 @@
-using System.Runtime.CompilerServices;
+using System.Net;
+using System.Runtime.CompilerServices;
 using InertiaCore.Props;
 using InertiaCore.Utils;
 using Microsoft.AspNetCore.Html;
@@ -27,7 +28,7 @@ public static class Inertia
 
     public static LocationResult Location(string url) => _factory.Location(url);
 
-    public static BackResult Back(string? fallbackUrl = null) => _factory.Back(fallbackUrl);
+    public static BackResult Back(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther) => _factory.Back(fallbackUrl, statusCode);
 
     public static void Share(string key, object? value) => _factory.Share(key, value);
 
diff --git a/InertiaCore/ResponseFactory.cs b/InertiaCore/ResponseFactory.cs
index 2b0244f..be3e88b 100644
--- a/InertiaCore/ResponseFactory.cs
+++ b/InertiaCore/ResponseFactory.cs
@@ -20,7 +20,7 @@ internal interface IResponseFactory
     public void Version(Func<string?> version);
     public string? GetVersion();
     public LocationResult Location(string url);
-    public BackResult Back(string? fallbackUrl = null);
+    public BackResult Back(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther);
     public void Share(string key, object? value);
     public void Share(IDictionary<string, object?> data);
     public AlwaysProp Always(object? value);
@@ -109,7 +109,7 @@ public async Task<IHtmlContent> Html(dynamic model)
     };
 
     public LocationResult Location(string url) => new(url);
-    public BackResult Back(string? fallbackUrl = null) => new(fallbackUrl);
+    public BackResult Back(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther) => new(fallbackUrl, statusCode);
 
     public void Share(string key, object? value)
     {
diff --git a/InertiaCore/Utils/BackResult.cs b/InertiaCore/Utils/BackResult.cs
index fdc422d..d3bd70d 100644
--- a/InertiaCore/Utils/BackResult.cs
+++ b/InertiaCore/Utils/BackResult.cs
@@ -7,14 +7,19 @@ namespace InertiaCore.Utils;
 public class BackResult : IActionResult
 {
     private readonly string _fallbackUrl;
+    private readonly HttpStatusCode _statusCode;
 
-    public BackResult(string? fallbackUrl = null) => _fallbackUrl = fallbackUrl ?? "/";
+    public BackResult(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther) =>
+        (_fallbackUrl, _statusCode) = (fallbackUrl ?? "/", statusCode);
 
-    public async Task ExecuteResultAsync(ActionContext context)
+    public Task ExecuteResultAsync(ActionContext context)
     {
         var referrer = context.HttpContext.Request.Headers.Referer.ToString();
         var redirectUrl = !string.IsNullOrEmpty(referrer) ? referrer : _fallbackUrl;
 
-        await new RedirectResult(redirectUrl).ExecuteResultAsync(context);
+        context.HttpContext.Response.StatusCode = (int)_statusCode;
+        context.HttpContext.Response.Headers.Location = redirectUrl;
+
+        return Task.CompletedTask;
     }
 }
diff --git a/InertiaCoreTests/UnitTestBack.cs b/InertiaCoreTests/UnitTestBack.cs
index 4c666fe..5122a07 100644
--- a/InertiaCoreTests/UnitTestBack.cs
+++ b/InertiaCoreTests/UnitTestBack.cs
@@ -31,32 +31,22 @@ public async Task TestBackWithInertiaRequest()
         var responseHeaders = new HeaderDictionary();
         var response = new Mock<HttpResponse>();
         response.SetupGet(r => r.Headers).Returns(responseHeaders);
-        response.SetupGet(r => r.StatusCode).Returns(0);
-        response.SetupSet(r => r.StatusCode = It.IsAny<int>());
+        response.SetupProperty(r => r.StatusCode);
 
         var request = new Mock<HttpRequest>();
         request.SetupGet(r => r.Headers).Returns(headers);
 
-        // Set up service provider
-        var services = new ServiceCollection();
-        services.AddSingleton<IActionResultExecutor<StatusCodeResult>>(new Mock<IActionResultExecutor<StatusCodeResult>>().Object);
-        services.AddLogging();
-        services.AddMvc();
-        var serviceProvider = services.BuildServiceProvider();
-
         var httpContext = new Mock<HttpContext>();
         httpContext.SetupGet(c => c.Request).Returns(request.Object);
         httpContext.SetupGet(c => c.Response).Returns(response.Object);
-        httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
-        httpContext.SetupGet(c => c.Items).Returns(new Dictionary<object, object?>());
-        httpContext.SetupGet(c => c.Features).Returns(new FeatureCollection());
 
         var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
 
         await backResult.ExecuteResultAsync(context);
 
-        // Since there's no referrer, it should redirect to the fallback URL
-        response.Verify(r => r.Redirect("/fallback", false), Times.Once);
+        // Should set status code to 303 (SeeOther) and location header to fallback URL
+        Assert.That(response.Object.StatusCode, Is.EqualTo(303));
+        Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("/fallback"));
     }
 
     [Test]
@@ -71,32 +61,16 @@ public async Task TestBackWithReferrerHeader()
         };
 
         var responseHeaders = new HeaderDictionary();
-        string? redirectLocation = null;
         var response = new Mock<HttpResponse>();
         response.SetupGet(r => r.Headers).Returns(responseHeaders);
-        response.SetupGet(r => r.StatusCode).Returns(0);
-        response.SetupSet(r => r.StatusCode = It.IsAny<int>());
-        response.Setup(r => r.Redirect(It.IsAny<string>()))
-            .Callback<string>(location => redirectLocation = location);
+        response.SetupProperty(r => r.StatusCode);
 
         var request = new Mock<HttpRequest>();
         request.SetupGet(r => r.Headers).Returns(headers);
-        request.SetupGet(r => r.Scheme).Returns("https");
-        request.SetupGet(r => r.Host).Returns(new HostString("example.com"));
-
-        // Set up service provider
-        var services = new ServiceCollection();
-        services.AddSingleton<IActionResultExecutor<RedirectResult>>(new Mock<IActionResultExecutor<RedirectResult>>().Object);
-        services.AddSingleton<ILoggerFactory>(new Mock<ILoggerFactory>().Object);
-        services.AddMvc();
-        var serviceProvider = services.BuildServiceProvider();
 
         var httpContext = new Mock<HttpContext>();
         httpContext.SetupGet(c => c.Request).Returns(request.Object);
         httpContext.SetupGet(c => c.Response).Returns(response.Object);
-        httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
-        httpContext.SetupGet(c => c.Items).Returns(new Dictionary<object, object?>());
-        httpContext.SetupGet(c => c.Features).Returns(new FeatureCollection());
 
         var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
 
@@ -104,6 +78,10 @@ public async Task TestBackWithReferrerHeader()
         Assert.That(result, Is.Not.Null);
 
         await result.ExecuteResultAsync(context);
+
+        // Should set status code to 303 (SeeOther) and location header to referrer
+        Assert.That(response.Object.StatusCode, Is.EqualTo(303));
+        Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("https://example.com/previous-page"));
     }
 
     [Test]
@@ -115,32 +93,16 @@ public async Task TestBackWithFallbackUrl()
         var headers = new HeaderDictionary();
 
         var responseHeaders = new HeaderDictionary();
-        string? redirectLocation = null;
         var response = new Mock<HttpResponse>();
         response.SetupGet(r => r.Headers).Returns(responseHeaders);
-        response.SetupGet(r => r.StatusCode).Returns(0);
-        response.SetupSet(r => r.StatusCode = It.IsAny<int>());
-        response.Setup(r => r.Redirect(It.IsAny<string>()))
-            .Callback<string>(location => redirectLocation = location);
+        response.SetupProperty(r => r.StatusCode);
 
         var request = new Mock<HttpRequest>();
         request.SetupGet(r => r.Headers).Returns(headers);
-        request.SetupGet(r => r.Scheme).Returns("https");
-        request.SetupGet(r => r.Host).Returns(new HostString("example.com"));
-
-        // Set up service provider
-        var services = new ServiceCollection();
-        services.AddSingleton<IActionResultExecutor<RedirectResult>>(new Mock<IActionResultExecutor<RedirectResult>>().Object);
-        services.AddSingleton<ILoggerFactory>(new Mock<ILoggerFactory>().Object);
-        services.AddMvc();
-        var serviceProvider = services.BuildServiceProvider();
 
         var httpContext = new Mock<HttpContext>();
         httpContext.SetupGet(c => c.Request).Returns(request.Object);
         httpContext.SetupGet(c => c.Response).Returns(response.Object);
-        httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
-        httpContext.SetupGet(c => c.Items).Returns(new Dictionary<object, object?>());
-        httpContext.SetupGet(c => c.Features).Returns(new FeatureCollection());
 
         var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
 
@@ -148,6 +110,10 @@ public async Task TestBackWithFallbackUrl()
         Assert.That(result, Is.Not.Null);
 
         await result.ExecuteResultAsync(context);
+
+        // Should set status code to 303 (SeeOther) and location header to custom fallback
+        Assert.That(response.Object.StatusCode, Is.EqualTo(303));
+        Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("/custom-fallback"));
     }
 
     [Test]
@@ -159,31 +125,48 @@ public async Task TestBackWithDefaultFallback()
         var headers = new HeaderDictionary();
 
         var responseHeaders = new HeaderDictionary();
-        string? redirectLocation = null;
         var response = new Mock<HttpResponse>();
         response.SetupGet(r => r.Headers).Returns(responseHeaders);
-        response.SetupGet(r => r.StatusCode).Returns(0);
-        response.SetupSet(r => r.StatusCode = It.IsAny<int>());
-        response.Setup(r => r.Redirect(It.IsAny<string>()))
-            .Callback<string>(location => redirectLocation = location);
+        response.SetupProperty(r => r.StatusCode);
 
         var request = new Mock<HttpRequest>();
         request.SetupGet(r => r.Headers).Returns(headers);
-        request.SetupGet(r => r.Scheme).Returns("https");
-        request.SetupGet(r => r.Host).Returns(new HostString("example.com"));
 
-        // Set up service provider
-        var services = new ServiceCollection();
-        services.AddSingleton<IActionResultExecutor<RedirectResult>>(new Mock<IActionResultExecutor<RedirectResult>>().Object);
-        services.AddSingleton<ILoggerFactory>(new Mock<ILoggerFactory>().Object);
-        var serviceProvider = services.BuildServiceProvider();
+        var httpContext = new Mock<HttpContext>();
+        httpContext.SetupGet(c => c.Request).Returns(request.Object);
+        httpContext.SetupGet(c => c.Response).Returns(response.Object);
+
+        var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
+
+        var result = backResult as IActionResult;
+        Assert.That(result, Is.Not.Null);
+
+        await result.ExecuteResultAsync(context);
+
+        // Should set status code to 303 (SeeOther) and location header to default fallback
+        Assert.That(response.Object.StatusCode, Is.EqualTo(303));
+        Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("/"));
+    }
+
+    [Test]
+    [Description("Test Back function with permanent redirect.")]
+    public async Task TestBackWithPermanentRedirect()
+    {
+        var backResult = _factory.Back("/fallback", HttpStatusCode.MovedPermanently);
+
+        var headers = new HeaderDictionary();
+
+        var responseHeaders = new HeaderDictionary();
+        var response = new Mock<HttpResponse>();
+        response.SetupGet(r => r.Headers).Returns(responseHeaders);
+        response.SetupProperty(r => r.StatusCode);
+
+        var request = new Mock<HttpRequest>();
+        request.SetupGet(r => r.Headers).Returns(headers);
 
         var httpContext = new Mock<HttpContext>();
         httpContext.SetupGet(c => c.Request).Returns(request.Object);
         httpContext.SetupGet(c => c.Response).Returns(response.Object);
-        httpContext.SetupGet(c => c.RequestServices).Returns(serviceProvider);
-        httpContext.SetupGet(c => c.Items).Returns(new Dictionary<object, object?>());
-        httpContext.SetupGet(c => c.Features).Returns(new FeatureCollection());
 
         var context = new ActionContext(httpContext.Object, new RouteData(), new ActionDescriptor());
 
@@ -191,6 +174,10 @@ public async Task TestBackWithDefaultFallback()
         Assert.That(result, Is.Not.Null);
 
         await result.ExecuteResultAsync(context);
+
+        // Should set status code to 301 (MovedPermanently) and location header to fallback
+        Assert.That(response.Object.StatusCode, Is.EqualTo(301));
+        Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("/fallback"));
     }
 
 }

From 52c43a25b585dde8094c5410ddabb27f39a89f4b Mon Sep 17 00:00:00 2001
From: Kacper Ziubryniewicz <kacper@novaro.media>
Date: Sun, 9 Nov 2025 09:49:09 +0100
Subject: [PATCH 7/7] Format

---
 InertiaCore/Inertia.cs           | 3 ++-
 InertiaCore/ResponseFactory.cs   | 4 +++-
 InertiaCoreTests/UnitTestBack.cs | 9 ---------
 3 files changed, 5 insertions(+), 11 deletions(-)

diff --git a/InertiaCore/Inertia.cs b/InertiaCore/Inertia.cs
index 0676a7a..fd99eb2 100644
--- a/InertiaCore/Inertia.cs
+++ b/InertiaCore/Inertia.cs
@@ -28,7 +28,8 @@ public static class Inertia
 
     public static LocationResult Location(string url) => _factory.Location(url);
 
-    public static BackResult Back(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther) => _factory.Back(fallbackUrl, statusCode);
+    public static BackResult Back(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther) =>
+        _factory.Back(fallbackUrl, statusCode);
 
     public static void Share(string key, object? value) => _factory.Share(key, value);
 
diff --git a/InertiaCore/ResponseFactory.cs b/InertiaCore/ResponseFactory.cs
index be3e88b..69bff94 100644
--- a/InertiaCore/ResponseFactory.cs
+++ b/InertiaCore/ResponseFactory.cs
@@ -109,7 +109,9 @@ public async Task<IHtmlContent> Html(dynamic model)
     };
 
     public LocationResult Location(string url) => new(url);
-    public BackResult Back(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther) => new(fallbackUrl, statusCode);
+
+    public BackResult Back(string? fallbackUrl = null, HttpStatusCode statusCode = HttpStatusCode.SeeOther) =>
+        new(fallbackUrl, statusCode);
 
     public void Share(string key, object? value)
     {
diff --git a/InertiaCoreTests/UnitTestBack.cs b/InertiaCoreTests/UnitTestBack.cs
index 5122a07..f3d0edc 100644
--- a/InertiaCoreTests/UnitTestBack.cs
+++ b/InertiaCoreTests/UnitTestBack.cs
@@ -1,16 +1,8 @@
-using System.Collections.Generic;
 using System.Net;
-using InertiaCore;
-using InertiaCore.Extensions;
-using InertiaCore.Utils;
 using Microsoft.AspNetCore.Http;
-using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.Abstractions;
-using Microsoft.AspNetCore.Mvc.Infrastructure;
 using Microsoft.AspNetCore.Routing;
-using Microsoft.Extensions.DependencyInjection;
-using Microsoft.Extensions.Logging;
 using Moq;
 
 namespace InertiaCoreTests;
@@ -179,5 +171,4 @@ public async Task TestBackWithPermanentRedirect()
         Assert.That(response.Object.StatusCode, Is.EqualTo(301));
         Assert.That(responseHeaders["Location"].ToString(), Is.EqualTo("/fallback"));
     }
-
 }