Skip meta.profile entries without a string value when picking profiles

src/Firely.Fhir.Validation/Impl/ResourceSchema.cs

@@ -55,7 +55,10 @@ internal override ElementSchema WithMembers(IEnumerable<IAssertion> members)
         /// </summary>
         internal static Canonical[] GetMetaProfileSchemas(PocoNode instance, ValidationSettings vc, ValidationState state)
         {
-            var profiles = instance.NavigateTo("meta.profile").Select(pn => new Canonical((string)pn.GetValue()!)).ToArray();
+            // An entry can lack a value (e.g. when it only carries an extension), and a lenient parse keeps a non-string
+            // JSON value as is. Neither names a profile, so both are skipped.
+            var profiles = instance.NavigateTo("meta.profile").Select(pn => pn.GetValue()).OfType<string>()
+                .Select(profile => new Canonical(profile)).ToArray();
 
             return callback(vc.SelectValidationProfiles).Invoke(instance.GetLocation(), profiles, instance, vc);
 

test/Firely.Fhir.Validation.Compilation.Tests.Shared/ResourceSchemaValidationTests.cs

@@ -43,6 +43,23 @@ public void DoesValidateBasedOnActualType()
             result.Evidence.Should().ContainSingle(ass => ass is IssueAssertion && ((IssueAssertion)ass).IssueNumber == Issue.CONTENT_ELEMENT_CHOICE_INVALID_INSTANCE_TYPE.Code);
         }
 
+        [Fact]
+        public void ValidatesMetaProfileWithoutValue()
+        {
+            // A meta.profile entry may carry just an extension, and then names no profile to validate against.
+#if STU3
+            // STU3's data-absent-reason has the context datatype '*', which the validator does not accept yet.
+            var extension = "{\"url\":\"http://hl7.org/fhir/StructureDefinition/iso21090-nullFlavor\",\"valueCode\":\"UNK\"}";
+#else
+            var extension = "{\"url\":\"http://hl7.org/fhir/StructureDefinition/data-absent-reason\",\"valueCode\":\"unknown\"}";
+#endif
+            var json = "{\"resourceType\":\"Patient\",\"meta\":{\"_profile\":[{\"extension\":[" + extension + "]}]}}";
+            var p = new FhirJsonDeserializer().DeserializeResource(json);
+            var schema = _fixture.SchemaResolver.GetSchema(Canonical.ForCoreType("Resource"))!;
+            var result = schema.Validate(p.ToPocoNode(), _fixture.NewValidationSettings());
+            result.IsSuccessful.Should().BeTrue();
+        }
+
         private Meta setMetaForVersion(string uri)
         {
 #if STU3

test/Firely.Fhir.Validation.Tests/Impl/ResourceSchemaTests.cs

@@ -1,6 +1,7 @@
 using FluentAssertions;
 using Hl7.Fhir.ElementModel;
 using Hl7.Fhir.Model;
+using Hl7.Fhir.Serialization;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using System;
 using System.Linq;
@@ -36,6 +37,18 @@ static Canonical[] callback(string location, Canonical[] orignalMetaProfiles, Po
             static Canonical[] declineAll(string location, Canonical[] orignalMetaProfiles, PocoNode input, ValidationSettings vc) => [];
         }
 
+        [DataTestMethod]
+        [DataRow("{\"resourceType\":\"Patient\",\"meta\":{\"profile\":[\"profile1\",null],\"_profile\":[null,{\"extension\":[{\"url\":\"http://example.org/ext\",\"valueString\":\"x\"}]}]}}")]
+        [DataRow("{\"resourceType\":\"Patient\",\"meta\":{\"profile\":[\"profile1\",5]}}")]
+        public void MetaProfileWithoutStringValueIsSkipped(string json)
+        {
+            var instance = new FhirJsonDeserializer(new DeserializerSettings().UsingMode(DeserializationMode.SyntaxOnly)).DeserializeResource(json).ToPocoNode();
+
+            var result = ResourceSchema.GetMetaProfileSchemas(instance, new ValidationSettings(), new ValidationState());
+
+            result.Should().BeEquivalentTo(new Canonical[] { "profile1" });
+        }
+
         [TestMethod]
         public void GetImposedProfilesTest()
         {