fix MapsterMapper#281 null propagation

ashwindersingh · Nov 22, 2020 · 773f64a · 773f64a
1 parent bd353d4
commit 773f64a
Show file tree

Hide file tree

Showing 2 changed files with 21 additions and 0 deletions.
diff --git a/src/Mapster.Tests/WhenFlattening.cs b/src/Mapster.Tests/WhenFlattening.cs
@@ -37,6 +37,11 @@ public class E
  public decimal BClass_Total { get; set; }
  }
 
+ public class F
+ {
+ public decimal? BClass_Total { get; set; }
+ }
+
  public class ModelObject
  {
  public DateTime BaseDate { get; set; }
@@ -106,6 +111,20 @@ public void PropertyTest_NameWithUnderscore()
  Assert.IsTrue(e.BClass_Total == 250);
  }
 
+ [TestMethod]
+ public void PropertyTest_NullPropagation()
+ {
+ var f = TypeAdapter.Adapt<C, F>(new C { BClass = new B { Total = 250 } });
+
+ Assert.IsNotNull(f);
+ Assert.IsTrue(f.BClass_Total == 250);
+
+ var f2 = TypeAdapter.Adapt<C, F>(new C { BClass = null });
+
+ Assert.IsNotNull(f2);
+ Assert.IsNull(f2.BClass_Total);
+ }
+
  [TestMethod]
  public void ShouldUseNestedObjectPropertyMembers()
  {

diff --git a/src/Mapster/Utils/ExpressionEx.cs b/src/Mapster/Utils/ExpressionEx.cs
@@ -317,6 +317,8 @@ public static Expression ApplyNullPropagation(this Expression getter)
  if (expr.CanBeNull())
  {
  var compareNull = Expression.Equal(expr, Expression.Constant(null, expr.Type));
+ if (!result.Type.CanBeNull())
+ result = Expression.Convert(result, typeof(Nullable<>).MakeGenericType(result.Type));
  result = Expression.Condition(compareNull, result.Type.CreateDefault(), result);
  }