Fixed logic for FluentAssertions WithHeader (#959)

src/WireMock.Net.FluentAssertions/Assertions/WireMockAssertions.cs

@@ -149,15 +149,15 @@ public class WireMockAssertions
 
         using (new AssertionScope($"header \"{expectedKey}\" from requests sent with value(s)"))
         {
-            var headerValues = _headers.First(h => h.Key == expectedKey).Value;
+            var matchingHeaderValues = _headers.Where(h => h.Key == expectedKey).SelectMany(h => h.Value.ToArray()).ToArray();
 
             if (expectedValues.Length == 1)
             {
-                headerValues.Should().Contain(expectedValues.First(), because, becauseArgs);
+                matchingHeaderValues.Should().Contain(expectedValues.First(), because, becauseArgs);
             }
             else
             {
-                var trimmedHeaderValues = string.Join(",", headerValues.Select(x => x)).Split(',').Select(x => x.Trim()).ToList();
+                var trimmedHeaderValues = string.Join(",", matchingHeaderValues.Select(x => x)).Split(',').Select(x => x.Trim()).ToList();
                 foreach (var expectedValue in expectedValues)
                 {
                     trimmedHeaderValues.Should().Contain(expectedValue, because, becauseArgs);

test/WireMock.Net.Tests/FluentAssertions/WireMockAssertionsTests.cs

@@ -210,6 +210,36 @@ public class WireMockAssertionsTests : IDisposable
             .Be($"{string.Join(NewLine, missingValue1Message, missingValue2Message)}{NewLine}");
     }
 
+    [Fact]
+    public async Task HaveReceivedACall_WithHeader_ShouldCheckAllRequests()
+    {
+        // Arrange
+        using var server = WireMockServer.Start();
+        using var client = server.CreateClient();
+
+        // Act 1
+        await client.SendAsync(new HttpRequestMessage(HttpMethod.Get, "/")
+        {
+            Headers =
+            {
+                Authorization = new AuthenticationHeaderValue("Bearer", "invalidToken")
+            }
+        });
+
+        // Act 2
+        await client.SendAsync(new HttpRequestMessage(HttpMethod.Get, "/")
+        {
+            Headers =
+            {
+                Authorization = new AuthenticationHeaderValue("Bearer", "validToken")
+            }
+        });
+
+        // Assert
+        server.Should().HaveReceivedACall().WithHeader("Authorization", "Bearer invalidToken");
+        server.Should().HaveReceivedACall().WithHeader("Authorization", "Bearer validToken");
+    }
+
     [Fact]
     public async Task HaveReceivedACall_AtUrl_WhenACallWasMadeToUrl_Should_BeOK()
     {