Added Week to the RollingInterval enum.

Added a test for Week in RollingIntervalExtenstionsTests class.

Author: camerontbelt

src/Serilog.Sinks.File/RollingInterval.cs

@@ -34,6 +34,11 @@ public enum RollingInterval
         /// </summary>
         Month,
 
+        /// <summary>
+        /// Roll every calendar week. Filenames will have <code>yyyyMMdd</code> appended.
+        /// </summary>
+        Week,
+
         /// <summary>
         /// Roll every day. Filenames will have <code>yyyyMMdd</code> appended.
         /// </summary>

src/Serilog.Sinks.File/Sinks/File/RollingIntervalExtensions.cs

@@ -28,6 +28,8 @@ public static string GetFormat(this RollingInterval interval)
                     return "yyyy";
                 case RollingInterval.Month:
                     return "yyyyMM";
+                case RollingInterval.Week:
+                    return "yyyyMMdd";
                 case RollingInterval.Day:
                     return "yyyyMMdd";
                 case RollingInterval.Hour:
@@ -49,6 +51,8 @@ public static string GetFormat(this RollingInterval interval)
                     return new DateTime(instant.Year, 1, 1, 0, 0, 0, instant.Kind);
                 case RollingInterval.Month:
                     return new DateTime(instant.Year, instant.Month, 1, 0, 0, 0, instant.Kind);
+                case RollingInterval.Week:
+                    return new DateTime(instant.Year, instant.Month, instant.Day, 0, 0, 0, instant.Kind);
                 case RollingInterval.Day:
                     return new DateTime(instant.Year, instant.Month, instant.Day, 0, 0, 0, instant.Kind);
                 case RollingInterval.Hour:
@@ -72,6 +76,8 @@ public static string GetFormat(this RollingInterval interval)
                     return current.Value.AddYears(1);
                 case RollingInterval.Month:
                     return current.Value.AddMonths(1);
+                case RollingInterval.Week:
+                    return current.Value.AddDays(7);
                 case RollingInterval.Day:
                     return current.Value.AddDays(1);
                 case RollingInterval.Hour:

test/Serilog.Sinks.File.Tests/RollingIntervalExtensionsTests.cs

@@ -12,6 +12,8 @@ public class RollingIntervalExtensionsTests
             new object[]{ RollingInterval.Year,     new DateTime(2018, 06, 01),           new DateTime(2018, 01, 01), new DateTime(2019, 01, 01) },
             new object[]{ RollingInterval.Month,    new DateTime(2018, 01, 01),           new DateTime(2018, 01, 01), new DateTime(2018, 02, 01) },
             new object[]{ RollingInterval.Month,    new DateTime(2018, 01, 14),           new DateTime(2018, 01, 01), new DateTime(2018, 02, 01) },
+            new object[]{ RollingInterval.Week,     new DateTime(2018, 01, 01),           new DateTime(2018, 01, 01), new DateTime(2018, 01, 08) },
+            new object[]{ RollingInterval.Week,     new DateTime(2018, 01, 01, 12, 0, 0), new DateTime(2018, 01, 01), new DateTime(2018, 01, 08) },
             new object[]{ RollingInterval.Day,      new DateTime(2018, 01, 01),           new DateTime(2018, 01, 01), new DateTime(2018, 01, 02) },
             new object[]{ RollingInterval.Day,      new DateTime(2018, 01, 01, 12, 0, 0), new DateTime(2018, 01, 01), new DateTime(2018, 01, 02) },
             new object[]{ RollingInterval.Hour,     new DateTime(2018, 01, 01, 0, 0, 0),  new DateTime(2018, 01, 01), new DateTime(2018, 01, 01, 1, 0, 0) },

test/Serilog.Sinks.File.Tests/Serilog.Sinks.File.Tests.csproj

@@ -18,6 +18,8 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.5.0" />
+    <PackageReference Include="System.Runtime" Version="4.3.0" />
+    <PackageReference Include="xunit.extensibility.core" Version="2.4.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.1" />
     <PackageReference Include="xunit" Version="2.4.1" />
   </ItemGroup>