Changed DateTime.Now to use TimeProvider.

Added a new TestTimeProvider to test solution, passed in through options. This allows for easier testing as well as customization for the user in case they want to change provider. Fixed Age tests (provider always returns first day of month, allowing simplified age calculation in tests). Signed-off-by: Johannes Tegnér <johannes@jitesoft.com>
personnummer · Dec 29, 2024 · ad8dcda · ad8dcda
1 parent 0831d07
commit ad8dcda
Show file tree

Hide file tree

Showing 4 changed files with 51 additions and 17 deletions.
diff --git a/Personnummer.Tests/CoordinationNumberTests.cs b/Personnummer.Tests/CoordinationNumberTests.cs
@@ -103,17 +103,19 @@ public void TestParseInvalidCn(PersonnummerData ssn)
         [ClassData(typeof(ValidCnDataProvider))]
         public void TestAgeCn(PersonnummerData ssn)
         {
+            var timeProvider = new TestTimeProvider();
+
             int day = int.Parse(ssn.LongFormat.Substring(ssn.LongFormat.Length - 6, 2)) - 60;
             string strDay = day < 10 ? $"0{day}" : day.ToString();
 
-            DateTime dt    = DateTime.ParseExact(ssn.LongFormat.Substring(0, ssn.LongFormat.Length - 6) + strDay, "yyyyMMdd", CultureInfo.InvariantCulture, DateTimeStyles.None);
-            int      years = DateTime.Now.Year - dt.Year;
+            DateTime dt = DateTime.ParseExact(ssn.LongFormat.Substring(0, ssn.LongFormat.Length - 6) + strDay, "yyyyMMdd", CultureInfo.InvariantCulture, DateTimeStyles.None);
+            int years = timeProvider.GetLocalNow().Year - dt.Year;
 
-            Assert.Equal(years, Personnummer.Parse(ssn.SeparatedLong, new Personnummer.Options { AllowCoordinationNumber = true }).Age);
-            Assert.Equal(years, Personnummer.Parse(ssn.SeparatedFormat, new Personnummer.Options { AllowCoordinationNumber = true }).Age);
-            Assert.Equal(years, Personnummer.Parse(ssn.LongFormat, new Personnummer.Options { AllowCoordinationNumber = true }).Age);
+            Assert.Equal(years, Personnummer.Parse(ssn.SeparatedLong, new Personnummer.Options { AllowCoordinationNumber = true, TimeProvider = timeProvider }).Age);
+            Assert.Equal(years, Personnummer.Parse(ssn.SeparatedFormat, new Personnummer.Options { AllowCoordinationNumber = true, TimeProvider = timeProvider }).Age);
+            Assert.Equal(years, Personnummer.Parse(ssn.LongFormat, new Personnummer.Options { AllowCoordinationNumber = true, TimeProvider = timeProvider }).Age);
             // Du to age not being possible to fetch from >100 year short format without separator, we aught to check this here.
-            Assert.Equal(years > 99 ? years - 100 : years, Personnummer.Parse(ssn.ShortFormat, new Personnummer.Options { AllowCoordinationNumber = true }).Age);
+            Assert.Equal(years > 99 ? years - 100 : years, Personnummer.Parse(ssn.ShortFormat, new Personnummer.Options { AllowCoordinationNumber = true, TimeProvider = timeProvider }).Age);
         }
 
 

diff --git a/Personnummer.Tests/PersonnummerTests.cs b/Personnummer.Tests/PersonnummerTests.cs
@@ -80,14 +80,15 @@ public void TestParseInvalid(PersonnummerData ssn)
         [ClassData(typeof(ValidSsnDataProvider))]
         public void TestAge(PersonnummerData ssn)
         {
+            var timeProvider = new TestTimeProvider();
             DateTime dt = DateTime.ParseExact(ssn.LongFormat.Substring(0, ssn.LongFormat.Length - 4), "yyyyMMdd", CultureInfo.InvariantCulture, DateTimeStyles.None);
-            int years = DateTime.Now.Year - dt.Year;
+            int years = timeProvider.GetLocalNow().Year - dt.Year;
 
-            Assert.Equal(years, Personnummer.Parse(ssn.SeparatedLong, new Personnummer.Options { AllowCoordinationNumber = false }).Age);
-            Assert.Equal(years, Personnummer.Parse(ssn.SeparatedFormat, new Personnummer.Options { AllowCoordinationNumber = false }).Age);
-            Assert.Equal(years, Personnummer.Parse(ssn.LongFormat, new Personnummer.Options { AllowCoordinationNumber = false }).Age);
+            Assert.Equal(years, Personnummer.Parse(ssn.SeparatedLong, new Personnummer.Options { AllowCoordinationNumber = false, TimeProvider = timeProvider }).Age);
+            Assert.Equal(years, Personnummer.Parse(ssn.SeparatedFormat, new Personnummer.Options { AllowCoordinationNumber = false, TimeProvider = timeProvider }).Age);
+            Assert.Equal(years, Personnummer.Parse(ssn.LongFormat, new Personnummer.Options { AllowCoordinationNumber = false, TimeProvider = timeProvider }).Age);
             // Du to age not being possible to fetch from >100 year short format without separator, we aught to check this here.
-            Assert.Equal(years > 99 ? years - 100 : years, Personnummer.Parse(ssn.ShortFormat, new Personnummer.Options { AllowCoordinationNumber = false }).Age);
+            Assert.Equal(years > 99 ? years - 100 : years, Personnummer.Parse(ssn.ShortFormat, new Personnummer.Options { AllowCoordinationNumber = false, TimeProvider = timeProvider }).Age);
         }
 
         [Theory]

diff --git a/Personnummer.Tests/TestTimeProvider.cs b/Personnummer.Tests/TestTimeProvider.cs
@@ -0,0 +1,20 @@
+using System;
+
+namespace Personnummer.Tests;
+
+/// <summary>
+/// TimeProvider which always returns the same date: 2025 01 01 00:00:01 with UTC timezone on local time.
+/// </summary>
+public class TestTimeProvider : TimeProvider
+{
+    public override DateTimeOffset GetUtcNow()
+    {
+        return new DateTimeOffset(
+            new DateOnly(2025, 1, 1),
+            new TimeOnly(0,0,0, 1),
+            TimeSpan.Zero
+        );
+    }
+
+    public override TimeZoneInfo LocalTimeZone { get; } = TimeZoneInfo.Utc;
+}
diff --git a/Personnummer/Personnummer.cs b/Personnummer/Personnummer.cs
@@ -18,6 +18,15 @@ public Options()
             public bool AllowCoordinationNumber { get; set; } = true;
 
             public bool AllowInterimNumber { get; set; } = false;
+
+            /// <summary>
+            /// TimeProvider to use in calculations which are time dependent.<br/>
+            /// Uses `GetLocalNow` method.
+            /// <remarks>
+            /// Defaults to System provider.
+            /// </remarks>
+            /// </summary>
+            public TimeProvider TimeProvider { get; set; } = TimeProvider.System;
         }
 
         #region Fields and Properties
@@ -28,7 +37,7 @@ public int Age
         {
             get
             {
-                var now = DateTime.Now;
+                var now = _options.TimeProvider.GetLocalNow();
                 var age = now.Year - Date.Year;
 
                 if (now.Month >= Date.Month && now.Day > Date.Day)
@@ -64,6 +73,8 @@ public int Age
 
         #endregion
 
+        private readonly Options _options;
+
         /// <summary>
         /// Create a new Personnummber object from a string.
         ///
@@ -74,15 +85,15 @@ public int Age
         /// <param name="options">Options object.</param>
         public Personnummer(string ssn, Options? options = null)
         {
-            options ??= new Options();
+            _options = options ?? new Options();
             if (ssn.Length > 13 || ssn.Length < 10)
             {
                 var state = ssn.Length < 10 ? "short" : "long";
                 throw new PersonnummerException($"Input string too {state}");
             }
 
 
-            if (options.Value.AllowInterimNumber == false && Regex.IsMatch(ssn.Trim(), InterimTest))
+            if (_options.AllowInterimNumber == false && Regex.IsMatch(ssn.Trim(), InterimTest))
             {
                 throw new PersonnummerException(
                     $"{ssn} contains non-integer characters and options are set to not allow interim numbers"
@@ -113,7 +124,7 @@ public Personnummer(string ssn, Options? options = null)
             }
             else
             {
-                int born = DateTime.Now.Year - int.Parse(decade);
+                int born = TimeProvider.System.GetLocalNow().Year - int.Parse(decade);
                 if (groups["separator"].Value.Length != 0 && groups["separator"].Value == "+")
                 {
                     born -= 100;
@@ -124,7 +135,7 @@ public Personnummer(string ssn, Options? options = null)
 
             // Create date time object.
             int day = int.Parse(groups["day"].Value);
-            if (options.Value.AllowCoordinationNumber)
+            if (_options.AllowCoordinationNumber)
             {
                 IsCoordinationNumber = day > 60;
                 day = IsCoordinationNumber ? day - 60 : day;
@@ -153,7 +164,7 @@ public Personnummer(string ssn, Options? options = null)
             }
 
             var num = groups["numbers"].Value;
-            if (options.Value.AllowInterimNumber)
+            if (_options.AllowInterimNumber)
             {
                  num = Regex.Replace(num, InterimTest, "1");
             }