Change FileResult.WithLastModified's input to nullable.

Author: faddiv

src/FluentAssertions.AspNetCore.Mvc/FileResultAssertions.cs

@@ -110,7 +110,7 @@ public FileResultAssertions WithFileDownloadName(string expectedFileDownloadName
         /// <param name="reasonArgs">
         ///     Zero or more objects to format using the placeholders in <see cref="reason" />.
         /// </param>
-        public FileResultAssertions WithLastModified(DateTimeOffset expectedLastModified, string reason = "",
+        public FileResultAssertions WithLastModified(DateTimeOffset? expectedLastModified, string reason = "",
             params object[] reasonArgs)
         {
             var actualLastModified = FileResultSubject.LastModified;

tests/FluentAssertions.AspNetCore.Mvc.Tests/FileResultAssertions_Tests.cs

@@ -57,23 +57,30 @@ public void WithFileDownloadName_GivenUnexpected_ShouldFail()
                 .WithMessage(failureMessage);
         }
 
-        [Fact]
-        public void WithLastModified_GivenExpectedValue_ShouldPass()
+        [Theory]
+        [InlineData("2009-06-15 13:45:30 -7h")]
+        [InlineData(null)]
+        public void WithLastModified_GivenExpectedValue_ShouldPass(string dateText)
         {
             var result = TestDataGenerator.CreateFileContentResult();
-            result.LastModified = DateTimeOffset.Parse("2009-06-15T13:45:30.0000000-07:00");
+            result.LastModified = TestDataGenerator.CreateDateTimeOffset(dateText);
 
-            result.Should().BeFileResult().WithLastModified(DateTimeOffset.Parse("2009-06-15T13:45:30.0000000-07:00"));
+            result.Should().BeFileResult()
+                .WithLastModified(TestDataGenerator.CreateDateTimeOffset(dateText));
         }
 
-        [Fact]
-        public void WithLastModified_GivenUnexpected_ShouldFail()
+        [Theory]
+        [InlineData("2010-07-16 14:46:31 -6h", "2009-06-15 13:45:30 -7h")]
+        [InlineData(null, "2009-06-15 13:45:30 -7h")]
+        [InlineData("2010-07-16 14:46:31 -6h", null)]
+        public void WithLastModified_GivenUnexpected_ShouldFail(
+            string expected, string actual)
         {
-            var actualValue = DateTimeOffset.Parse("2009-06-15T13:45:30.0000000-07:00");
-            var expectedValue = DateTimeOffset.Parse("2010-07-16T14:46:31.0000000-06:00");
+            var actualValue = TestDataGenerator.CreateDateTimeOffset(actual);
+            var expectedValue = TestDataGenerator.CreateDateTimeOffset(expected);
             var result = TestDataGenerator.CreateFileContentResult();
             result.LastModified = actualValue;
-            var failureMessage = "Expected \"FileResult.LastModified\" to be '<2010-07-16 14:46:31 -6h>' but found '<2009-06-15 13:45:30 -7h>'";
+            var failureMessage = $"Expected \"FileResult.LastModified\" to be '<{expected ?? "null"}>' but found '<{actual ?? "null"}>'";
 
             Action a = () => result.Should().BeFileResult().WithLastModified(expectedValue);
 

tests/FluentAssertions.AspNetCore.Mvc.Tests/Helpers/TestDataGenerator.cs

@@ -1,6 +1,9 @@
 using Microsoft.AspNetCore.Mvc;
+using System;
+using System.Globalization;
 using System.IO;
 using System.Text;
+using System.Text.RegularExpressions;
 
 namespace FluentAssertions.AspNetCore.Mvc.Tests.Helpers
 {
@@ -45,5 +48,19 @@ public static byte[] CreateBytes(string content = "")
             var bytes = Encoding.UTF8.GetBytes(content);
             return bytes;
         }
+
+        public static DateTimeOffset? CreateDateTimeOffset(string dateText)
+        {
+            if (dateText == null)
+                return null;
+            var match = dateRegex.Match(dateText);
+            return new DateTimeOffset(
+                DateTime.Parse(match.Groups[1].Value, CultureInfo.InvariantCulture),
+                TimeSpan.FromHours(int.Parse(match.Groups[2].Value, CultureInfo.InvariantCulture)));
+        }
+
+        private static readonly Regex dateRegex
+            = new Regex(@"^(\d{4}-\d{2}-\d{2} \d{1,2}:\d{2}:\d{2}) (-?\d+)h$");
+
     }
 }