Add support for IsNullOrWhiteSpace and improve tests

Author: nickevansuk

Source/Schema.NET/OneOrMany{T}.cs

@@ -107,7 +107,7 @@ public int Count
         /// <param name="item">The single item value.</param>
         /// <returns>The result of the conversion.</returns>
 #pragma warning disable CA2225 // Operator overloads have named alternates
-        public static implicit operator OneOrMany<T>(T item) => new OneOrMany<T>(item);
+        public static implicit operator OneOrMany<T>(T item) => item != null && item.GetType() == typeof(string) && string.IsNullOrWhiteSpace(item as string) ? default : new OneOrMany<T>(item);
 #pragma warning restore CA2225 // Operator overloads have named alternates
 
         /// <summary>
@@ -125,7 +125,7 @@ public int Count
         /// <param name="list">The list of values.</param>
         /// <returns>The result of the conversion.</returns>
 #pragma warning disable CA2225 // Operator overloads have named alternates
-        public static implicit operator OneOrMany<T>(List<T> list) => new OneOrMany<T>(list);
+        public static implicit operator OneOrMany<T>(List<T> list) => new OneOrMany<T>(list.Where(x => x != null && !(x.GetType() == typeof(string) && string.IsNullOrWhiteSpace(x as string))));
 #pragma warning restore CA2225 // Operator overloads have named alternates
 
         /// <summary>

Tests/Schema.NET.Test/OneOrManyTest.cs

@@ -237,5 +237,50 @@ public void GetHashCode_OneItem_HashCodeEqualToSingleItem() =>
         [Fact]
         public void GetHashCode_TwoItems_HashCodeEqualToTwoItems() =>
             Assert.Equal(NET.HashCode.OfEach(new List<int>() { 1, 2 }), new OneOrMany<int>(1, 2).GetHashCode());
+
+        [Theory]
+        [InlineData(null)]
+        [InlineData("")]
+        [InlineData(" ")]
+        [InlineData("  ")]
+        public void ToString_EmptyOrWhiteSpace_BookOmitsNameProperty(string name)
+        {
+            var book = new Book() { Name = name };
+            Assert.Equal("{\"@context\":\"http://schema.org\",\"@type\":\"Book\"}", book.ToString());
+        }
+
+        [Theory]
+        [InlineData(null)]
+        [InlineData("")]
+        [InlineData(" ")]
+        [InlineData("  ")]
+        public void ToString_EmptyOrWhiteSpace_BookOmitsNamePropertyFromList(string name)
+        {
+            var book = new Book() { Name = new List<string> { "Hamlet", name } };
+            Assert.Equal("{\"@context\":\"http://schema.org\",\"@type\":\"Book\",\"name\":\"Hamlet\"}", book.ToString());
+        }
+
+        [Theory]
+        [InlineData(null)]
+        [InlineData("")]
+        [InlineData(" ")]
+        [InlineData("  ")]
+        public void ToString_EmptyOrWhiteSpace_OrganizationOmitsAddressProperty(string address)
+        {
+            var organization = new Organization() { Address = address };
+            Assert.Equal("{\"@context\":\"http://schema.org\",\"@type\":\"Organization\"}", organization.ToString());
+        }
+
+        [Theory]
+        [InlineData(null)]
+        [InlineData("")]
+        [InlineData(" ")]
+        [InlineData("  ")]
+        public void ToString_EmptyOrWhiteSpace_OrganizationOmitsNamePropertyFromList(string address)
+        {
+            var organization = new Organization() { Name = new List<string> { "Cardiff, UK", address } };
+            Assert.Equal("{\"@context\":\"http://schema.org\",\"@type\":\"Organization\",\"name\":\"Cardiff, UK\"}", organization.ToString());
+        }
+
     }
 }

Tests/Schema.NET.Test/core/EventTest.cs

@@ -8,7 +8,7 @@ namespace Schema.NET.Test
     // https://developers.google.com/search/docs/data-types/events
     public class EventTest
     {
-        private static readonly string NullTelephone = null;
+        private static readonly string NullString = null;
         private static readonly ItemAvailability? NullItemAvailability = null;
 
         private readonly Event @event = new Event()
@@ -39,7 +39,8 @@ public class EventTest
                     Price = 30M, // Recommended
                     PriceCurrency = "USD", // Recommended
                     Availability = ItemAvailability.InStock, // Recommended
-                    ValidFrom = new DateTimeOffset(2017, 1, 20, 16, 20, 0, TimeSpan.FromHours(-8)) // Recommended
+                    ValidFrom = new DateTimeOffset(2017, 1, 20, 16, 20, 0, TimeSpan.FromHours(-8)), // Recommended
+                    Category = NullString,
                 },
                 new Offer
                 {
@@ -53,7 +54,7 @@ public class EventTest
             Performer = new Person() // Recommended
             {
                 Name = "Andy Lagunoff", // Recommended
-                Telephone = NullTelephone // Should be ignored
+                Telephone = NullString // Should be ignored
             }
         };