fixed based on pull request comments, added tests

hapi-fhir-base/src/main/java/ca/uhn/fhir/util/TerserUtil.java

@@ -158,15 +158,19 @@ public final class TerserUtil {
 		});
 	}
 
-	public static boolean equals(IBase theItem1, IBase theItem2){
+	private static Method getMethod(IBase item){
 		Method method = null;
-		for (Method m : theItem1.getClass().getDeclaredMethods()) {
+		for (Method m : item.getClass().getDeclaredMethods()) {
 			if (m.getName().equals("equalsDeep")) {
 				method = m;
 				break;
 			}
 		}
-		final Method m = method;
+		return method;
+	}
+
+	public static boolean equals(IBase theItem1, IBase theItem2){
+		final Method m = getMethod(theItem1);
 
 		return equals(theItem1, theItem2, m);
 	}
@@ -183,18 +187,8 @@ public final class TerserUtil {
 	}
 
 	private static boolean contains(IBase theItem, List<IBase> theItems) {
-		Method method = null;
+		final Method m = getMethod(theItem);
-		for (Method m : theItem.getClass().getDeclaredMethods()) {
+		return theItems.stream().anyMatch(i -> equals(i, theItem, m));
-			if (m.getName().equals("equalsDeep")) {
-				method = m;
-				break;
-			}
-		}
-
-		final Method m = method;
-		return theItems.stream().anyMatch(i -> {
-			return equals(i, theItem, m);
-		});
 	}
 
 	/**

hapi-fhir-server-mdm/src/main/java/ca/uhn/fhir/mdm/rules/matcher/ExtensionMatcher.java

@@ -11,27 +11,24 @@ import java.util.List;
 public class ExtensionMatcher implements IMdmFieldMatcher{
 	@Override
 	public boolean matches(FhirContext theFhirContext, IBase theLeftBase, IBase theRightBase, boolean theExact, String theIdentifierSystem) {
-		List<? extends IBaseExtension<?, ?>> leftExtension = null;
+		if (!(theLeftBase instanceof IBaseHasExtensions && theRightBase instanceof IBaseHasExtensions)){
-		List<? extends IBaseExtension<?, ?>> rightExtension = null;
-		if (theLeftBase instanceof IBaseHasExtensions && theRightBase instanceof IBaseHasExtensions){
-			leftExtension = ((IBaseHasExtensions) theLeftBase).getExtension();
-			rightExtension = ((IBaseHasExtensions) theRightBase).getExtension();
-		}
-		else{
 			return false;
 		}
+		List<? extends IBaseExtension<?, ?>> leftExtension = ((IBaseHasExtensions) theLeftBase).getExtension();
+		List<? extends IBaseExtension<?, ?>> rightExtension = ((IBaseHasExtensions) theRightBase).getExtension();
 
 		boolean match = false;
 
+		if (theIdentifierSystem != null) {
+			leftExtension.removeIf(iBaseExtension -> !iBaseExtension.getUrl().equals(theIdentifierSystem));
+			rightExtension.removeIf(iBaseExtension -> !iBaseExtension.getUrl().equals(theIdentifierSystem));
+		}
+
 		for (IBaseExtension leftExtensionValue : leftExtension) {
-			if (leftExtensionValue.getUrl().equals(theIdentifierSystem) || theIdentifierSystem == null) {
 			for (IBaseExtension rightExtensionValue : rightExtension) {
-					if (rightExtensionValue.getUrl().equals(theIdentifierSystem) || theIdentifierSystem == null) {
 				match |= ExtensionUtil.equals(leftExtensionValue, rightExtensionValue);
 			}
 		}
-			}
-		}
 		return match;
 	}
 }

hapi-fhir-server-mdm/src/test/java/ca/uhn/fhir/mdm/rules/matcher/ExtensionMatcherR4Test.java

@@ -2,6 +2,7 @@ package ca.uhn.fhir.mdm.rules.matcher;
 
 
 import org.hl7.fhir.r4.model.IntegerType;
+import org.hl7.fhir.r4.model.Organization;
 import org.hl7.fhir.r4.model.Patient;
 import org.hl7.fhir.r4.model.StringType;
 import org.junit.jupiter.api.Test;
@@ -83,5 +84,12 @@ public class ExtensionMatcherR4Test extends BaseMatcherR4Test {
 		assertTrue(MdmMatcherEnum.EXTENSION_ANY_ORDER.match(ourFhirContext, patient1, patient2, false, null));
 	}
 
+	@Test
+	public void testPatientWithNoExtension(){
+		Patient patient1 = new Patient();
+		Patient patient2 = new Patient();
+
+		assertFalse(MdmMatcherEnum.EXTENSION_ANY_ORDER.match(ourFhirContext, patient1, patient2, false, null));
+	}
 
 }

hapi-fhir-structures-r4/src/test/java/ca/uhn/fhir/util/TerserUtilTest.java

@@ -6,6 +6,7 @@ import org.hl7.fhir.r4.model.DateTimeType;
 import org.hl7.fhir.r4.model.DateType;
 import org.hl7.fhir.r4.model.Enumerations;
 import org.hl7.fhir.r4.model.Extension;
+import org.hl7.fhir.r4.model.HumanName;
 import org.hl7.fhir.r4.model.Identifier;
 import org.hl7.fhir.r4.model.Patient;
 import org.junit.jupiter.api.Test;
@@ -237,4 +238,27 @@ class TerserUtilTest {
 		assertThat(p2.getName(), hasSize(1));
 		assertThat(p2.getName().get(0).getGiven(), hasSize(2));
 	}
+
+
+	@Test
+	void testEqualsFunction(){
+		Patient p1 = new Patient();
+		Patient p2 = new Patient();
+
+		p1.addName(new HumanName().setFamily("family").addGiven("asd"));
+		p2.addName(new HumanName().setFamily("family").addGiven("asd"));
+
+		assertTrue(TerserUtil.equals(p1, p2));
+	}
+
+	@Test
+	void testEqualsFunctionNotEqual(){
+		Patient p1 = new Patient();
+		Patient p2 = new Patient();
+
+		p1.addName(new HumanName().setFamily("family").addGiven("asd"));
+		p2.addName(new HumanName().setFamily("family").addGiven("asd1"));
+
+		assertFalse(TerserUtil.equals(p1, p2));
+	}
 }