#178: Add .OrDefault() typed extension method. Thanks @anorborg!

HISTORY.md

@@ -1,5 +1,6 @@
-## v24.0.1
+## v24.1.0
 * Added `nullWeight` parameter to `.OrNull()` extension method for weighted generation of null values.
+* Added new `.OrDefault()` extension method. Thanks @anorborg!
 
 ## v24.0.0
 * BREAKING: Deterministic values may have changed. Parity with **faker.js** @ 07f39bd3.

Source/Bogus.Tests/Bogus.Tests.csproj

@@ -2,6 +2,7 @@
 
   <PropertyGroup>
     <TargetFrameworks>net471;netcoreapp2.0</TargetFrameworks>
+    <LangVersion>7.3</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>

Source/Bogus.Tests/GitHubIssues/Issue178.cs

@@ -12,18 +12,40 @@ public void weighted_null_check()
       {
          var f = new Faker();
          var mostlyNull = Enumerable.Range(1, 100)
-            .Select(n => (int?)n.OrNull(f, 0.9))
+            .Select(n => (int?)n.OrNull(f, 0.9f))
             .Count( n => !n.HasValue);
 
          mostlyNull.Should().BeGreaterThan(80);
 
-
          var mostlyNotNull = Enumerable.Range(1, 100)
-            .Select(n => (int?)n.OrNull(f, 0.1))
+            .Select(n => (int?)n.OrNull(f, 0.1f))
             .Count(n => !n.HasValue);
 
          mostlyNotNull.Should().BeLessThan(20);
+      }
+
+      [Fact]
+      public void weighted_default_check()
+      {
+         var f = new Faker();
+         var mostlyDefault = Enumerable.Range(1, 100)
+            .Select(n => n.OrDefault(f, 0.9f))
+            .Count(n => n == default);
+
+         mostlyDefault.Should().BeGreaterThan(80);
+
+         var mostlyNotDefault = Enumerable.Range(1, 100)
+            .Select(n => n.OrDefault(f, 0.1f))
+            .Count(n => n == default);
+
+         mostlyNotDefault.Should().BeLessThan(20);
+
+         var mostlyNotDefaultObject = Enumerable.Range(1, 100)
+            .Select( n => new object())
+            .Select(s => s.OrDefault(f, 0.1f))
+            .Count(s => s == null);
 
+         mostlyNotDefaultObject.Should().BeLessThan(20);
       }
    }
 }

Source/Bogus/Extensions/ExtensionsForFakerT.cs

@@ -29,10 +29,22 @@ public static List<T> GenerateBetween<T>(this Faker<T> faker, int min, int max,
       /// </summary>
       /// <param name="f">The Faker facade. This is usually the f from f => lambda.</param>
       /// <param name="nullWeight">The probability of null occuring. Range [1.0f - 0.0f] (100% and 0%) respectively. For example, if 15% null is desired pass nullWeight = 0.15f.</param>
-      public static object OrNull(this object value, Faker f, double nullWeight = 0.5f)
+      public static object OrNull(this object value, Faker f, float nullWeight = 0.5f)
       {
          if (nullWeight > 1 || nullWeight < 0) throw new ArgumentOutOfRangeException(nameof(nullWeight), $".{nameof(OrNull)}() {nameof(nullWeight)} of '{nullWeight}' must be between 1.0f and 0.0f. ");
          return f.Random.Float() > nullWeight ? value : null;
       }
+
+      /// <summary>
+      /// Helpful extension for creating randomly default(T) values for <seealso cref="Faker{T}"/>.RuleFor() rules.
+      /// Example: .RuleFor(x=>x.Prop, f=>f.Random.Word().OrDefault(f))
+      /// </summary>
+      /// <param name="f">The Faker facade. This is usually the f from f => lambda.</param>
+      /// <param name="defaultWeight">The probability of default(T) occuring. Range [1.0f - 0.0f] (100% and 0%) respectively. For example, if 15% default(T) is desired pass defaultWeight = 0.15f.</param>
+      public static T OrDefault<T>(this T value, Faker f, float defaultWeight = 0.5f)
+      {
+         if (defaultWeight > 1 || defaultWeight < 0) throw new ArgumentOutOfRangeException(nameof(defaultWeight), $".{nameof(OrDefault)}() {nameof(defaultWeight)} of '{defaultWeight}' must be between 1.0f and 0.0f. ");
+         return f.Random.Float() > defaultWeight ? value : default;
+      }
    }
 }