Fix nullpointer exception when reporting with TakeAllSelector (#947)

dspot/src/main/java/eu/stamp_project/dspot/common/report/output/selector/takeall/json/TestClassJSON.java

@@ -0,0 +1,13 @@
+package eu.stamp_project.dspot.common.report.output.selector.takeall.json;
+
+/**
+ * Created by Carolin BRANDT
+ * [email protected]
+ * on 05/14/20
+ */
+public class TestClassJSON implements eu.stamp_project.dspot.common.report.output.selector.TestClassJSON {
+
+    public String toString(){
+       return "";
+    }
+}

dspot/src/main/java/eu/stamp_project/dspot/selector/TakeAllSelector.java

@@ -4,6 +4,7 @@
 import eu.stamp_project.dspot.common.configuration.UserInput;
 import eu.stamp_project.dspot.common.report.output.selector.TestSelectorElementReport;
 import eu.stamp_project.dspot.common.report.output.selector.TestSelectorElementReportImpl;
+import eu.stamp_project.dspot.common.report.output.selector.takeall.json.TestClassJSON;
 import spoon.reflect.declaration.CtMethod;
 import spoon.reflect.declaration.CtType;
 
@@ -51,7 +52,7 @@ public List<CtMethod<?>> selectToKeep(List<CtMethod<?>> amplifiedTestToBeKept) {
 	public TestSelectorElementReport report() {
 		final String report = "Amplification results with " + this.selectedAmplifiedTest.size() + " new tests.";
 		reset();
-		return new TestSelectorElementReportImpl(report, null, Collections.emptyList(), "");
+		return new TestSelectorElementReportImpl(report, new TestClassJSON(), Collections.emptyList(), "");
 	}
 
 	@Override

dspot/src/test/java/eu/stamp_project/dspot/selector/TakeAllSelectorTest.java

@@ -5,6 +5,7 @@
 
 import java.util.Collections;
 
+import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 
 /**
@@ -47,4 +48,9 @@ public void testSelector() throws Exception {
 		assertFalse(this.testSelectorUnderTest.getAmplifiedTestCases().isEmpty());
 		this.testSelectorUnderTest.report();
 	}
+
+	@Test
+	public void testReportForCollector() {
+		assertEquals("", this.testSelectorUnderTest.report().getReportForCollector());
+	}
 }