List Java Instru Test Information From JUnit Runner

base/test/android/javatests/src/org/chromium/base/test/BaseChromiumAndroidJUnitRunner.java

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.base.test;
 
+import android.app.Activity;
 import android.app.Application;
+import android.app.Instrumentation;
 import android.content.Context;
+import android.os.Bundle;
+import android.support.test.internal.runner.RunnerArgs;
+import android.support.test.internal.runner.TestExecutor;
+import android.support.test.internal.runner.TestRequest;
+import android.support.test.internal.runner.TestRequestBuilder;
 import android.support.test.runner.AndroidJUnitRunner;
 
+import org.chromium.base.Log;
 import org.chromium.base.multidex.ChromiumMultiDexInstaller;
 
 /**
  * A custom AndroidJUnitRunner that supports multidex installer.
  *
  * This class is the equivalent of BaseChromiumInstrumentationTestRunner in JUnit3. Please
  * beware that is this not a class runner. It is declared in test apk AndroidManifest.xml
  * <instrumentation>
  */
 public class BaseChromiumAndroidJUnitRunner extends AndroidJUnitRunner {
+    private Bundle mArguments;
+    private static final String LIST_ALL_TESTS_FLAG = "listAllTests";
+    private static final String TAG = "BaseJUnitRunner";
+
     @Override
     public Application newApplication(ClassLoader cl, String className, Context context)
             throws ClassNotFoundException, IllegalAccessException, InstantiationException {
         ChromiumMultiDexInstaller.install(new BaseChromiumRunnerCommon.MultiDexContextWrapper(
                 getContext(), getTargetContext()));
         BaseChromiumRunnerCommon.reorderDexPathElements(cl, getContext(), getTargetContext());
         return super.newApplication(cl, className, context);
     }
+
+    @Override
+    public void onCreate(Bundle arguments) {
+        super.onCreate(arguments);
+        mArguments = arguments;
+    }
+
+    @Override
+    public void onStart() {
+        if (getListTestFlag(mArguments) != null) {
+            Bundle results = new Bundle();
+            try {
+                TestExecutor.Builder executorBuilder = new TestExecutor.Builder(this);
+                executorBuilder.addRunListener(new TestListInstrumentationRunListener(
+                        getListTestFlag(mArguments).toString()));
+                TestRequest listTestRequest = createListTestRequest(mArguments);
+                results = executorBuilder.build().execute(listTestRequest);

[mikecase (-- gone --), 2017/07/11 21:14:51]

can you explain how this works? How did you make the tests not actually get run?

[the real yoland, 2017/07/14 03:15:46]

I am using the AndroidJUnitRunner's provided feature to log out test only (`-e
log true`)

+            } catch (RuntimeException e) {

[mikecase (-- gone --), 2017/07/11 21:14:51]

Should we actually be catching this? Will the exception show up in the python
output?

[the real yoland, 2017/07/14 03:15:46]

The failure stack trace will show up in the host side as output, and the host
script will raise Exception

+                final String msg = "Fatal exception when running tests";
+                Log.e(TAG, msg, e);
+                // report the exception to instrumentation out
+                results.putString(Instrumentation.REPORT_KEY_STREAMRESULT,
+                        msg + "\n" + Log.getStackTraceString(e));
+            }
+            finish(Activity.RESULT_OK, results);
+        } else {
+            super.onStart();
+        }
+    }
+
+    private TestRequest createListTestRequest(Bundle arguments) {
+        RunnerArgs runnerArgs =
+                new RunnerArgs.Builder().fromManifest(this).fromBundle(arguments).build();
+        TestRequestBuilder builder = new TestRequestBuilder(this, arguments);
+        builder.addApkToScan(getContext().getPackageCodePath());
+        builder.addFromRunnerArgs(runnerArgs);
+        return builder.build();
+    }
+
+    private static CharSequence getListTestFlag(Bundle arguments) {
+        return arguments != null ? arguments.getCharSequence(LIST_ALL_TESTS_FLAG) : null;
+    }
 }