Fix handling of non existing test history

Author: breskeby

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/test/rerun/RerunPlugin.java

@@ -48,7 +48,7 @@ public void apply(Project project) {
                 spec.getParameters().getInfoPath().set(settingsRoot);
             });
 
-        project.getTasks().withType(Test.class).configureEach(task -> configureTestTask(task, retryTestsProvider, objectFactory));
+        project.getTasks().withType(Test.class).configureEach(task -> configureTestTask(task, retryTestsProvider));
 
     }
 
@@ -62,17 +62,15 @@ interface Params extends BuildServiceParameters {
 
         public RetryTestsBuildService() {
             File failedTestsJsonFile = new File(getParameters().getInfoPath().getAsFile().get(), "failed-tests.json");
-
             if (failedTestsJsonFile.exists()) {
-                System.out.println("RetryTestsBuildService.RetryTestsBuildService");
                 try {
                     ObjectMapper objectMapper = new ObjectMapper();
                     this.failureReport = objectMapper.readValue(failedTestsJsonFile, FailedTestsReport.class);
                 } catch (IOException e) {
                     throw new RuntimeException("Failed to parse retry-tests.json", e);
                 }
             } else {
-                this.failureReport = new FailedTestsReport();
+                this.failureReport = null;
             }
         }
 

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/test/rerun/TestTaskConfigurer.java

@@ -12,10 +12,10 @@
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
 
+import org.elasticsearch.gradle.internal.test.rerun.model.FailedTestsReport;
 import org.elasticsearch.gradle.internal.test.rerun.model.TestCase;
 import org.elasticsearch.gradle.internal.test.rerun.model.WorkUnit;
 import org.gradle.api.file.Directory;
-import org.gradle.api.model.ObjectFactory;
 import org.gradle.api.provider.Provider;
 import org.gradle.api.tasks.testing.Test;
 import org.gradle.api.tasks.testing.TestDescriptor;
@@ -33,12 +33,13 @@ public final class TestTaskConfigurer {
 
     private TestTaskConfigurer() {}
 
-    public static void configureTestTask(
-        Test test,
-        Provider<RerunPlugin.RetryTestsBuildService> testsBuildServiceProvider,
-        ObjectFactory objectFactory
-    ) {
-        List<WorkUnit> workUnits = testsBuildServiceProvider.get().getFailureReport().getWorkUnits();
+    public static void configureTestTask(Test test, Provider<RerunPlugin.RetryTestsBuildService> testsBuildServiceProvider) {
+        FailedTestsReport failureReport = testsBuildServiceProvider.get().getFailureReport();
+        if (failureReport == null) {
+            // no historical test failures found
+            return;
+        }
+        List<WorkUnit> workUnits = failureReport.getWorkUnits();
         Optional<WorkUnit> first = workUnits.stream().filter(workunit -> workunit.getName().equals(test.getPath())).findFirst();
         if (first.isPresent()) {
             test.filter(testFilter -> {