Don't throw if a property is missing from DynamicJson, to allow for o…

…ptional property checks (#34026)

* Add tests for optional property scenarios

* Implement optional property check logic.

* Add back CanTestPropertyForNull test

* return null instead of DynamicJson(
ull)

* raw string literals

sdk/core/Azure.Core.Experimental/src/DynamicJson.cs

@@ -36,12 +36,17 @@ internal override void WriteTo(Stream stream)
             writer.Flush();
         }
 
-        private object GetProperty(string name)
+        private object? GetProperty(string name)
         {
-            return new DynamicJson(_element.GetProperty(name));
+            if (_element.TryGetProperty(name, out MutableJsonElement element))
+            {
+                return new DynamicJson(element);
+            }
+
+            return null;
         }
 
-        private object GetViaIndexer(object index)
+        private object? GetViaIndexer(object index)
         {
             switch (index)
             {

sdk/core/Azure.Core.Experimental/src/MutableJsonElement.cs

@@ -50,7 +50,7 @@ public MutableJsonElement GetProperty(string name)
         {
             if (!TryGetProperty(name, out MutableJsonElement value))
             {
-                throw new InvalidOperationException($"{_path} does not containe property called {name}");
+                throw new InvalidOperationException($"{_path} does not contain property called {name}");
             }
 
             return value;

sdk/core/Azure.Core.Experimental/tests/DynamicJsonTests.cs

@@ -291,6 +291,68 @@ public void CanMakeChangesAndAddNewProperty()
             Assert.AreEqual(2, (int)jsonData.Bar);
         }
 
+        [Test]
+        public void CanCheckOptionalProperty()
+        {
+            dynamic json = GetDynamicJson("""
+                {
+                  "Foo" : "foo"
+                }
+                """);
+
+            // Property is present
+            Assert.IsFalse(json.Foo == null);
+
+            // Property is absent
+            Assert.IsTrue(json.Bar == null);
+        }
+
+        [Test]
+        public void CanCheckOptionalPropertyWithChanges()
+        {
+            dynamic json = GetDynamicJson("""
+                {
+                  "Foo" : "foo",
+                  "Bar" : {
+                    "A" : "a"
+                  }
+                }
+            """);
+
+            // Add property Baz
+            json.Baz = "baz";
+
+            // Remove property A
+            json.Bar = new { B = "b" };
+
+            // Properties are present
+            Assert.IsFalse(json.Foo == null);
+            Assert.IsFalse(json.Bar.B == null);
+            Assert.IsFalse(json.Baz == null);
+
+            // Properties are absent
+            Assert.IsTrue(json.Bar.A == null);
+        }
+
+        [Test]
+        public void CanSetOptionalProperty()
+        {
+            dynamic json = GetDynamicJson("""
+                {
+                  "Foo" : "foo"
+                }
+                """);
+
+            // Property is absent
+            Assert.IsTrue(json.OptionalValue == null);
+
+            json.OptionalValue = 5;
+
+            // Property is present
+            Assert.IsFalse(json.OptionalValue == null);
+            Assert.AreEqual(5, (int)json.OptionalValue);
+        }
+
         #region Helpers
         internal static dynamic GetDynamicJson(string json)
         {
@@ -300,6 +362,6 @@ internal static dynamic GetDynamicJson(string json)
         internal class CustomType
         {
         }
-#endregion
+        #endregion
     }
 }

sdk/core/Azure.Core.Experimental/tests/public/JsonDataArrayTests.cs

@@ -163,7 +163,7 @@ public void CanGetArrayPropertyIndex()
         public void CanGetObjectMemberViaArrayIndex()
         {
             dynamic data = JsonDataTestHelpers.CreateFromJson(
-                @"{ ""value"": [ { ""tag"": ""tagValue"" }, 2, 3] }"
+                """{ "value": [ { "tag": "tagValue" }, 2, 3] }"""
             );
 
             Assert.AreEqual("tagValue", (string)data.value[0].tag);
@@ -225,7 +225,7 @@ public void CanSetArrayPropertyIndex()
         public void CanSetObjectMemberViaArrayIndex()
         {
             dynamic data = JsonDataTestHelpers.CreateFromJson(
-                @"{ ""value"": [ { ""tag"": ""tagValue"" }, 2, 3] }"
+                """{ "value": [ { "tag": "tagValue" }, 2, 3] }"""
             );
 
             data.value[0].tag = "newValue";

sdk/core/Azure.Core.Experimental/tests/public/JsonDataPublicTests.cs

@@ -116,7 +116,6 @@ public void CanAccessProperties()
         }
 
         [Test]
-        [Ignore("To be implemented.")]
         public void CanTestPropertyForNull()
         {
             dynamic jsonData = new BinaryData("{ \"primitive\":\"Hello\", \"nested\": { \"nestedPrimitive\":true } }").ToDynamic();