[WIP] Add file attribute to JUnit report

components/context/build.gradle.kts

@@ -8,6 +8,16 @@ jmh {
   version = "1.28"
 }
 
+dependencies {
+  testImplementation("org.junit.jupiter:junit-jupiter-api:5.9.0")
+  testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.9.0")
+  implementation("org.junit.platform:junit-platform-launcher:1.9.0")
+}
+
 val excludedClassesInstructionCoverage by extra {
   listOf("datadog.context.ContextProviders") // covered by forked test
 }
+
+tasks.test {
+  systemProperty("junit.jupiter.extensions.autodetection.enabled", "true")
+}

components/context/src/main/resources/META-INF/services/org.junit.jupiter.api.extension.Extension

@@ -0,0 +1 @@
+datadog.context.GatherSourceFileInfoExtension

components/context/src/main/resources/META-INF/services/org.junit.platform.launcher.TestExecutionListener

@@ -0,0 +1 @@
+datadog.context.InsertSourceFileExtension

components/context/src/test/java/datadog/context/ContextKeyTest.java

@@ -19,7 +19,8 @@ class ContextKeyTest {
   void testConstructor(String name) {
     ContextKey<String> key = ContextKey.named(name);
     assertNotNull(key, "created key should not be null");
-    assertEquals(name, key.toString(), name + " label should be supported");
+    // assertEquals fails. remove '+ "X"' to fix.
+    assertEquals(name, key.toString() + "X", name + " label should be supported");
   }
 
   @Test

components/context/src/test/java/datadog/context/GatherSourceFileInfoExtension.java

@@ -0,0 +1,41 @@
+package datadog.context;
+
+import java.io.BufferedWriter;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.nio.file.Paths;
+import java.util.HashMap;
+import java.util.Map;
+import org.junit.jupiter.api.extension.ExtensionContext;
+import org.junit.jupiter.api.extension.TestInstancePostProcessor;
+
+public class GatherSourceFileInfoExtension implements TestInstancePostProcessor {
+  private static Map<String, String> sourceFiles = new HashMap<String, String>();
+
+  @Override
+  public void postProcessTestInstance(Object testInstance, ExtensionContext context)
+      throws IOException {
+    getTestData(context);
+  }
+
+  public static Map<String, String> getSourceFiles() {
+    return sourceFiles;
+  }
+
+  private static void getTestData(ExtensionContext context) throws IOException {
+    // get test classname and source file
+    String testClassName = context.getTestClass().get().getName();
+    String testClassPath = testClassName.replace(".", "/") + ".java";
+    String root = Paths.get("").toAbsolutePath().toString();
+    String absolutePath = root + "/src/test/java/" + testClassPath;
+    String subPath =
+        absolutePath.substring(absolutePath.indexOf("dd-trace-java") + "dd-trace-java".length());
+    // add info to sourceFiles map
+    sourceFiles.put(testClassName, subPath);
+    // print to sourceFiles.xml
+    BufferedWriter writer =
+        new BufferedWriter(new FileWriter(root + "/build/test-results/test/sourceFiles.xml"));
+    writer.write(sourceFiles.toString());
+    writer.close();
+  }
+}

components/context/src/test/java/datadog/context/InsertSourceFileExtension.java

@@ -0,0 +1,81 @@
+package datadog.context;
+
+import java.io.BufferedWriter;
+import java.io.FileWriter;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.Map;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import org.junit.platform.engine.TestExecutionResult;
+import org.junit.platform.launcher.TestExecutionListener;
+import org.junit.platform.launcher.TestIdentifier;
+import org.junit.platform.launcher.TestPlan;
+
+public class InsertSourceFileExtension implements TestExecutionListener {
+  @Override
+  public void executionStarted(TestIdentifier testIdentifier) {
+    System.out.println(testIdentifier.getDisplayName() + " test started.");
+  }
+
+  @Override
+  public void testPlanExecutionStarted(TestPlan testPlan) {
+    // does not print when tested locally
+    System.out.println("---testPlanExecutionStarted---");
+  }
+
+  @Override
+  public void executionFinished(
+      TestIdentifier testIdentifier, TestExecutionResult testExecutionResult) {
+    // get mapping of test classname to source file
+    Map<String, String> sourceFiles = GatherSourceFileInfoExtension.getSourceFiles();
+
+    String filePath = Paths.get("").toAbsolutePath() + "/build/test-results/test/";
+
+    // for each test...
+    for (String sourceFile : sourceFiles.keySet()) {
+      try {
+        // get xml report file
+        String fileContent =
+            new String(Files.readAllBytes(Paths.get(filePath + "TEST-" + sourceFile + ".xml")));
+
+        // add test source file info to report
+        Pattern pattern = Pattern.compile("<testcase(.*?)classname=\"(.*?)\"(.*?)>");
+        Matcher matcher = pattern.matcher(fileContent);
+        StringBuffer result = new StringBuffer();
+        while (matcher.find()) {
+          String begAttributes = matcher.group(1);
+          String className = matcher.group(2);
+          String endAttributes = matcher.group(3);
+
+          String fileAttribute = " file=\"" + sourceFiles.getOrDefault(className, "") + "\"";
+          String newTestCase =
+              "<testcase"
+                  + begAttributes
+                  + "classname=\""
+                  + className
+                  + "\""
+                  + fileAttribute
+                  + endAttributes
+                  + ">";
+          matcher.appendReplacement(result, newTestCase);
+        }
+        matcher.appendTail(result);
+
+        // set old filePath to new xml result
+        BufferedWriter writer =
+            new BufferedWriter(new FileWriter(filePath + "MOD-" + sourceFile + ".xml"));
+        writer.write(result.toString());
+        writer.close();
+      } catch (Exception e) {
+        System.out.println("Modifying XML files did not work.");
+      }
+    }
+  }
+
+  @Override
+  public void testPlanExecutionFinished(TestPlan testPlan) {
+    // does not print when tested locally
+    System.out.println("---testPlanExecutionFinished---.");
+  }
+}