Add PathEvaluatorLibrary test

src/main/java/org/smartregister/pathevaluator/PathEvaluatorLibrary.java

@@ -132,12 +132,14 @@ public FHIRPathStringValue evaluateStringExpression(DomainResource resource, Str
 	}
 
 	/**
-	 * Evaluates a String expression on a bundle and returns a String result or null
+	 * Evaluates a FHIR Path {@param expression} on a {@param bundle} and returns a String result
+	 * or null if the query fails or doesn't have results
 	 *
 	 * @param bundle
 	 * @param expression
 	 * @return
 	 */
+
 	public String extractStringFromBundle(Bundle bundle, String expression) {
 		try {
 			Iterator<FHIRPathNode> iterator = fhirPathEvaluator.evaluate(bundle, expression).iterator();
@@ -150,7 +152,8 @@ public String extractStringFromBundle(Bundle bundle, String expression) {
 
 
 	/**
-	 * Evaluates a String expression on a bundle and returns a List of String results
+	 * Evaluates a FHIR Path {@param expression} on a {@param bundle} and returns a List of String results
+	 * or null if the query fails or doesn't have results
 	 *
 	 * @param bundle
 	 * @param expression
@@ -168,18 +171,25 @@ public List<String> extractStringsFromBundle(Bundle bundle, String expression) {
 		}
 		return strs;
 	}
-
+
+	/**
+	 * Returns a {@link FHIRPathElementNode}'s value as a String
+	 * @param fhirPathElementNode
+	 * @return
+	 */
 	private String convertElementNodeValToStr(FHIRPathElementNode fhirPathElementNode) {
 		return fhirPathElementNode.getValue().asStringValue().string();
 	}
 
 	/**
-	 * Evaluates a String expression on a bundle and returns a Resource result or null
+	 * Evaluates a FHIR Path {@param expression} on a {@param bundle} and returns a List of {@link Element}s
+	 * or null if the query fails or doesn't have results
 	 *
 	 * @param bundle
 	 * @param expression
 	 * @return
 	 */
+
 	public List<Element> extractElementsFromBundle(Bundle bundle, String expression) {
 		List<Element> elements = new ArrayList<>();
 		try {
@@ -195,12 +205,14 @@ public List<Element> extractElementsFromBundle(Bundle bundle, String expression)
 	}
 
 	/**
-	 * Evaluates a String expression on a bundle and returns a Resource result or null
+	 * Evaluates a FHIR Path {@param expression} on a {@param bundle} and returns a {@link Resource} result
+	 * or null if the query fails or doesn't have results
 	 *
 	 * @param bundle
 	 * @param expression
 	 * @return
 	 */
+
 	public Resource extractResourceFromBundle(Bundle bundle, String expression) {
 		try {
 			Iterator<FHIRPathNode> iterator = fhirPathEvaluator.evaluate(bundle, expression).iterator();
@@ -210,20 +222,4 @@ public Resource extractResourceFromBundle(Bundle bundle, String expression) {
 			return null;
 		}
 	}
-
-	public void setLocationProvider(LocationProvider locationProvider) {
-		this.locationProvider = locationProvider;
-	}
-
-	public void setClientProvider(ClientProvider clientProvider) {
-		this.clientProvider = clientProvider;
-	}
-
-	public void setTaskProvider(TaskProvider taskProvider) {
-		this.taskProvider = taskProvider;
-	}
-
-	public void setEventProvider(EventProvider eventProvider) {
-		this.eventProvider = eventProvider;
-	}
 }

src/test/java/org/smartregister/pathevaluator/PathEvaluatorLibraryTest.java

@@ -8,8 +8,14 @@
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
+import java.io.File;
+import java.io.InputStream;
+import java.nio.file.Paths;
 import java.util.Calendar;
 
+import com.ibm.fhir.model.format.Format;
+import com.ibm.fhir.model.parser.FHIRParser;
+import com.ibm.fhir.model.resource.Bundle;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -30,6 +36,8 @@ public class PathEvaluatorLibraryTest {
 	private PathEvaluatorLibrary pathEvaluatorLibrary;
 
 	private Patient patient;
+
+	private Bundle deviceDefinitionBundle;
 
 	@Before
 	public void startUp() {
@@ -109,5 +117,26 @@ public void testEvaluateActionExpressions() {
 		node = pathEvaluatorLibrary.evaluateStringExpression(patient, "'Cancelled'");
 		assertEquals("Cancelled", node.string());
 	}
-
+
+	@Test
+	public void testExtractStringFromBundleShouldReturnCorrectString() throws Exception {
+		String str = pathEvaluatorLibrary.extractStringFromBundle(getDeviceDefinitionBundle(), "$this.entry.resource.where(identifier.where(value='d3fdac0e-061e-b068-2bed-5a95e803636f')).capability.where(type.where(text='instructions')).description.text");
+		assertEquals("Collect blood sample", str);
+	}
+
+	private Bundle getDeviceDefinitionBundle() throws Exception {
+		if (deviceDefinitionBundle == null) {
+			InputStream stream = getClass().getClassLoader().getResourceAsStream("DeviceDefinition.json");
+			deviceDefinitionBundle = FHIRParser.parser(Format.JSON).parse(stream);
+		}
+		return deviceDefinitionBundle;
+	}
+
+	public static String getTestFilePath() {
+		return getBasePackageFilePath() + "src/main/java/org/smartregister/pathevaluator" + File.separator;
+	}
+
+	public static String getBasePackageFilePath() {
+		return Paths.get(".").toAbsolutePath().normalize().toString() + File.separator;
+	}
 }