fix problem missing profiles on references in discriminators

org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/utils/FHIRPathEngine.java

@@ -235,6 +235,13 @@ public class FHIRPathEngine {
       }
       return res;
     }
+    public boolean hasType(String tn) {
+      if (type != null) {
+        return tn.equals(type);
+      } else {
+        return element.hasType(tn);
+      }
+    }
   }
   private IWorkerContext worker;
   private IEvaluationContext hostServices;
@@ -5472,7 +5479,7 @@ public class FHIRPathEngine {
    * @throws PathEngineException 
    * @throws DefinitionException 
    */
-  public TypedElementDefinition evaluateDefinition(ExpressionNode expr, StructureDefinition profile, TypedElementDefinition element, StructureDefinition source) throws DefinitionException {
+  public TypedElementDefinition evaluateDefinition(ExpressionNode expr, StructureDefinition profile, TypedElementDefinition element, StructureDefinition source, boolean dontWalkIntoReferences) throws DefinitionException {
     StructureDefinition sd = profile;
     TypedElementDefinition focus = null;
     boolean okToNotResolve = false;
@@ -5584,10 +5591,19 @@ public class FHIRPathEngine {
       } else {
         throw makeException(expr, I18nConstants.FHIRPATH_DISCRIMINATOR_CANT_FIND, expr.toString(), source.getUrl(), element.getElement().getId(), profile.getUrl());
       }
-    } else if (expr.getInner() == null) {
+    } else {
+      // gdg 26-02-2022. If we're walking towards a resolve() and we're on a reference, and  we try to walk into the reference
+      // then we don't do that. .resolve() is allowed on the Reference.reference, but the target of the reference will be defined
+      // on the Reference, not the reference.reference.
+      ExpressionNode next = expr.getInner();
+      if (dontWalkIntoReferences && focus.hasType("Reference") && next != null && next.getKind() == Kind.Name && next.getName().equals("reference")) {
+        next = next.getInner();
+      }
+      if (next == null) {
         return focus;
       } else {
-      return evaluateDefinition(expr.getInner(), sd, focus, profile);
+        return evaluateDefinition(next, sd, focus, profile, dontWalkIntoReferences);
+      }
     }
   }
 

org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/InstanceValidator.java

@@ -3405,13 +3405,17 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
       return elements;
     }
 
+    boolean dontFollowReference = false;
+    
     if (removeResolve) {  // if we're doing profile slicing, we don't want to walk into the last resolve.. we need the profile on the source not the target
       if (discriminator.equals("resolve()")) {
         elements.add(element);
         return elements;
       }
-      if (discriminator.endsWith(".resolve()"))
+      if (discriminator.endsWith(".resolve()")) {
         discriminator = discriminator.substring(0, discriminator.length() - 10);
+        dontFollowReference = true;
+      }
     }
 
     TypedElementDefinition ted = null;
@@ -3424,7 +3428,7 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
       throw new FHIRException(context.formatMessage(I18nConstants.DISCRIMINATOR_BAD_PATH, e.getMessage(), fp), e);
     }
     long t2 = System.nanoTime();
-    ted = fpe.evaluateDefinition(expr, profile, new TypedElementDefinition(element), srcProfile);
+    ted = fpe.evaluateDefinition(expr, profile, new TypedElementDefinition(element), srcProfile, dontFollowReference);
     timeTracker.sd(t2);
     if (ted != null)
       elements.add(ted.getElement());
@@ -3449,7 +3453,7 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
         }
         expr = fpe.parse(fp);
         t2 = System.nanoTime();
-        ted = fpe.evaluateDefinition(expr, profile, new TypedElementDefinition(element), srcProfile);
+        ted = fpe.evaluateDefinition(expr, profile, new TypedElementDefinition(element), srcProfile, dontFollowReference);
         timeTracker.sd(t2);
         if (ted != null)
           elements.add(ted.getElement());

org.hl7.fhir.validation/src/test/resources/txCache/3.0.2/snomed.cache

@@ -343,3 +343,12 @@ v: {
   "system" : "http://snomed.info/sct"
 }
 -------------------------------------------------------------------------------------
+{"code" : {
+  "system" : "http://snomed.info/sct",
+  "code" : "11181000146103"
+}, "valueSet" :null, "lang":"null", "useServer":"true", "useClient":"true", "guessSystem":"false", "valueSetMode":"ALL_CHECKS", "versionFlexible":"false"}####
+v: {
+  "severity" : "error",
+  "error" : "Unable to find code 11181000146103 in http://snomed.info/sct (version http://snomed.info/sct/900000000000207008/version/20210731); The code \"11181000146103\" is not valid in the system http://snomed.info/sct; The code provided (http://snomed.info/sct#11181000146103) is not valid in the value set 'All codes known to the system' (from http://tx.fhir.org/r3)"
+}
+-------------------------------------------------------------------------------------