Merge pull request #699 from paul-robson-validic/bug_check_loop_variable

Bug: Loop condition is always true

org.hl7.fhir.r4/src/main/java/org/hl7/fhir/r4/terminologies/ConceptMapEngine.java

@@ -64,7 +64,7 @@ public class ConceptMapEngine {
     for (ConceptMapGroupComponent g : cm.getGroup()) {
       for (SourceElementComponent e : g.getElement()) {
         if (code.equals(e.getCode())) {
-          if (e != null)
+          if (ct != null)
             throw new FHIRException("Unable to process translate "+code+" because multiple candidate matches were found in concept map "+cm.getUrl());
           ct = e;
           cg = g;

org.hl7.fhir.r4/src/test/java/org/hl7/fhir/r4/terminologies/ConceptMapEngineTest.java

@@ -0,0 +1,92 @@
+package org.hl7.fhir.r4.terminologies;
+
+import org.hl7.fhir.exceptions.FHIRException;
+import org.hl7.fhir.r4.context.SimpleWorkerContext;
+import org.hl7.fhir.r4.model.Coding;
+import org.hl7.fhir.r4.model.ConceptMap;
+import org.hl7.fhir.r4.model.Enumerations;
+import javax.annotation.Nonnull;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+class ConceptMapEngineTest {
+
+  private static final String CONCEPT_MAP_URL = "https://test-fhir.com/ConceptMap/fake";
+  public static final String SOURCE_CODE_STRING = "body-weight";
+  public static final String TARGET_CODE_STRING = "vital-signs";
+
+  @Test
+  @DisplayName("Coding is translated according to ConceptMap")
+  void codingTranslate() throws IOException {
+
+    final ConceptMap.SourceElementComponent sourceElementComponent = getSourceElementComponent();
+
+    final ConceptMapEngine conceptMapEngine = getConceptMapEngine(Arrays.asList(sourceElementComponent));
+    Coding coding = new Coding(null, SOURCE_CODE_STRING, "Body Weight");
+
+    Coding actual = conceptMapEngine.translate(coding, CONCEPT_MAP_URL);
+
+    assertEquals(TARGET_CODE_STRING, actual.getCode());
+  }
+
+  @Test
+  @DisplayName("Coding fails to translate due to multiple candidate matches in ConceptMap")
+  void codingTranslateFailsForMultipleCandidateMatches() throws IOException {
+
+    final ConceptMap.SourceElementComponent sourceElementComponent = getSourceElementComponent();
+
+    final ConceptMapEngine conceptMapEngine = getConceptMapEngine(Arrays.asList(sourceElementComponent,
+                                                sourceElementComponent
+                                              ));
+    Coding coding = new Coding(null, SOURCE_CODE_STRING, "Body Weight");
+
+    assertThrows(FHIRException.class, () -> {
+      conceptMapEngine.translate(coding, CONCEPT_MAP_URL);
+    });
+  }
+
+  @Nonnull
+  private ConceptMapEngine getConceptMapEngine(Collection<ConceptMap.SourceElementComponent> elements) throws IOException {
+    ConceptMap conceptMap = getConceptMap(elements);
+
+    SimpleWorkerContext simpleWorkerContext = mock(SimpleWorkerContext.class);
+    when(simpleWorkerContext.fetchResource(ConceptMap.class, CONCEPT_MAP_URL)).thenReturn(conceptMap);
+
+    return new ConceptMapEngine(simpleWorkerContext);
+  }
+
+  @Nonnull
+  private ConceptMap.SourceElementComponent getSourceElementComponent() {
+    ConceptMap.TargetElementComponent targetElementComponent = new ConceptMap.TargetElementComponent();
+    targetElementComponent.setCode(TARGET_CODE_STRING);
+    targetElementComponent.setEquivalence(Enumerations.ConceptMapEquivalence.EQUIVALENT);
+
+    ConceptMap.SourceElementComponent sourceElementComponent = new ConceptMap.SourceElementComponent();
+    sourceElementComponent.setCode(SOURCE_CODE_STRING);
+    sourceElementComponent.setTarget(Collections.singletonList(targetElementComponent));
+
+    return sourceElementComponent;
+  }
+
+  @Nonnull
+  private ConceptMap getConceptMap(Collection<ConceptMap.SourceElementComponent> elements) {
+
+    ConceptMap.ConceptMapGroupComponent conceptMapGroupComponent = new ConceptMap.ConceptMapGroupComponent();
+    for (ConceptMap.SourceElementComponent element : elements) {
+      conceptMapGroupComponent.addElement(element);
+    }
+    return new ConceptMap()
+      .addGroup(conceptMapGroupComponent)
+      .setUrl(CONCEPT_MAP_URL);
+  }
+}