c# - Unit Testing Action<T>? -

i using xunit , moq , trying test this:

public static class ienumerableextensions {     public static void foreach<t>(this ienumerable<t> list, action<t> action)     {         foreach (var item in list)             action(item);     } } 

i have tried this, no deal:

[fact]     public void foreach()     {         var list = new list<string>() { "string1", "string2" };          list.foreach(x =>         {             x += "-passed";         });          foreach (var item in list)             item.should().endwith("-passed");     } 

how go testing this?

in current test, modifying local x variable in action. create new list:

var list = new list<string>() { "string1", "string2" }; var dest = new list<string>();  list.foreach(s => { dest.add(x + "-passed"); });  foreach (var item in dest) {     item.should().endwith("-passed"); } 

you might want maintain count of how called:

int called = 0; list.foreach(s => {     dest.add(x + "-passed");     called++; });  assert.areequal(called, list.count);