Fix processing of // in File and add unit tests

Fixes #1457

Change-Id: I73ff292d87e8ba22a5900eac774d8ae576f05ef2

appinventor/components/src/com/google/appinventor/components/runtime/Form.java

@@ -25,6 +25,7 @@ import android.os.AsyncTask;
 import android.os.Build;
 import android.os.Bundle;
 import android.os.Handler;
+import android.support.annotation.VisibleForTesting;
 import android.support.v4.app.ActivityCompat;
 import android.support.v4.content.ContextCompat;
 import android.util.Log;
@@ -74,6 +75,7 @@ import com.google.appinventor.components.runtime.util.SdkLevel;
 import com.google.appinventor.components.runtime.util.ViewUtil;
 import org.json.JSONException;
 
+import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStream;
@@ -2530,13 +2532,7 @@ public class Form extends AppInventorCompatActivity
    */
   @SuppressWarnings({"WeakerAccess"})  // May be called by extensions
   public InputStream openAsset(String asset) throws IOException {
-    String path = getAssetPath(asset);
-    if (path.startsWith(ASSETS_PREFIX)) {
-      final AssetManager am = getAssets();
-      return am.open(path.substring(ASSETS_PREFIX.length()));
-    } else {
-      return FileUtil.openFile(URI.create(path));
-    }
+    return openAssetInternal(getAssetPath(asset));
   }
 
   /**
@@ -2563,13 +2559,21 @@ public class Form extends AppInventorCompatActivity
    * stream to prevent resource leaking.
    * @throws IOException if the asset is not found or cannot be read
    */
+  @SuppressWarnings("unused")  // May be called by extensions
   public InputStream openAssetForExtension(Component component, String asset) throws IOException {
-    String path = getAssetPathForExtension(component, asset);
+    return openAssetInternal(getAssetPathForExtension(component, asset));
+  }
+
+  @SuppressWarnings("WeakerAccess")  // Visible for testing
+  @VisibleForTesting
+  InputStream openAssetInternal(String path) throws IOException {
     if (path.startsWith(ASSETS_PREFIX)) {
       final AssetManager am = getAssets();
       return am.open(path.substring(ASSETS_PREFIX.length()));
-    } else {
+    } else if (path.startsWith("file:")) {
       return FileUtil.openFile(URI.create(path));
+    } else {
+      return FileUtil.openFile(path);
     }
   }
 }

appinventor/components/src/com/google/appinventor/components/runtime/ReplForm.java

@@ -62,7 +62,7 @@ public class ReplForm extends Form {
   private static final String LOG_TAG = ReplForm.class.getSimpleName();
   private AppInvHTTPD httpdServer = null;
   public static ReplForm topform;
-  private static final String REPL_ASSET_DIR =
+  public static final String REPL_ASSET_DIR =
     Environment.getExternalStorageDirectory().getAbsolutePath() +
     "/AppInventor/assets/";
   private static final String REPL_COMP_DIR = REPL_ASSET_DIR + "external_comps/";
@@ -402,7 +402,7 @@ public class ReplForm extends Form {
 
   @Override
   public String getAssetPath(String asset) {
-    return REPL_ASSET_DIR + asset;
+    return "file://" + REPL_ASSET_DIR + asset;
   }
 
   @Override

appinventor/components/tests/assets/com.google.appinventor.components.runtime.test/test.txt

+Sample extension asset

appinventor/components/tests/assets/test.txt

+Hello, world!

appinventor/components/tests/com/google/appinventor/components/runtime/FileTest.java

+// -*- mode: java; c-basic-offset: 2; -*-
+// Copyright © 2018 Massachusetts Institute of Technology, All rights reserved.
+// Released under the Apache License, Version 2.0
+// http://www.apache.org/licenses/LICENSE-2.0
+
+package com.google.appinventor.components.runtime;
+
+import android.Manifest;
+import android.os.Environment;
+import com.google.appinventor.components.runtime.shadows.ShadowActivityCompat;
+import com.google.appinventor.components.runtime.shadows.ShadowAsynchUtil;
+import com.google.appinventor.components.runtime.shadows.ShadowEventDispatcher;
+import com.google.appinventor.components.runtime.util.IOUtils;
+import org.junit.Before;
+import org.junit.Test;
+import org.robolectric.Shadows;
+import org.robolectric.annotation.Config;
+
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.nio.charset.Charset;
+
+/**
+ * Tests for the File component.
+ *
+ * @author ewpatton@mit.edu (Evan W. Patton)
+ */
+@Config(shadows = {ShadowActivityCompat.class})
+public class FileTest extends RobolectricTestBase {
+
+  private static final String TAG = FileTest.class.getSimpleName();
+  private static final String DATA = "test data";
+  protected static final String TARGET_FILE = "test.txt";
+  protected File file;
+
+  @Before
+  public void setUp() {
+    super.setUp();
+    file = new File(getForm());
+  }
+
+  /**
+   * Tests that the File component can read files when given the special file
+   * path "//". In a compiled app, this reads from the app's compiled assets.
+   * For the REPL, this reads from a special directory AppInventor/assets/
+   * on the external storage.
+   */
+  @Test
+  public void testFileDoubleSlash() {
+    grantFilePermissions();
+    file.ReadFrom("//" + TARGET_FILE);
+    ShadowAsynchUtil.runAllPendingRunnables();
+    runAllEvents();
+    ShadowEventDispatcher.assertEventFired(file, "GotText", "Hello, world!\n");
+  }
+
+  /**
+   * Tests that the File component can read files when given a relative file
+   * name. In a compiled app, this reads from the app's private data directory.
+   * For the REPL, this reads from a special directory AppInventor/data/
+   * on the external storage.
+   */
+  @Test
+  public void testFileRelative() {
+    grantFilePermissions();
+    writeTempFile(TARGET_FILE, DATA, false);
+    testReadFile(TARGET_FILE, DATA);
+  }
+
+  /**
+   * Tests that the File component can read files when given an absolute file
+   * name. In both compiled apps and the REPL, this reads from the given file
+   * from the root of the external storage.
+   */
+  @Test
+  public void testFileAbsolute() {
+    grantFilePermissions();
+    writeTempFile(TARGET_FILE, DATA, true);
+    testReadFile("/" + TARGET_FILE, DATA);
+  }
+
+  /**
+   * Tests that the file component will report a PermissionDenied event when
+   * the user denies a request for READ_EXTERNAL_STORAGE.
+   */
+  @Test
+  public void testFilePermissionDenied() {
+    denyFilePermissions();
+    file.ReadFrom("/" + TARGET_FILE);
+    ShadowActivityCompat.denyLastRequestedPermissions();
+    runAllEvents();
+    ShadowEventDispatcher.assertPermissionDenied(Manifest.permission.READ_EXTERNAL_STORAGE);
+  }
+
+  /// Helper functions
+
+  /**
+   * Helper function to grant read/write permissions to the app.
+   */
+  public void grantFilePermissions() {
+    Shadows.shadowOf(getForm()).grantPermissions(Manifest.permission.READ_EXTERNAL_STORAGE);
+    Shadows.shadowOf(getForm()).grantPermissions(Manifest.permission.WRITE_EXTERNAL_STORAGE);
+  }
+
+  /**
+   * Helper function to deny read/write permissions to the app.
+   */
+  public void denyFilePermissions() {
+    Shadows.shadowOf(getForm()).denyPermissions(Manifest.permission.READ_EXTERNAL_STORAGE);
+    Shadows.shadowOf(getForm()).denyPermissions(Manifest.permission.WRITE_EXTERNAL_STORAGE);
+  }
+
+  /**
+   * Write a temporary file to the file of the given {@code name} with the given
+   * {@code content}.
+   *
+   * @param name the name of the file to write
+   * @param content the content of the file
+   * @param external true if the file should be written to external storage,
+   *                 otherwise false.
+   * @return the absolute path of the file
+   */
+  public String writeTempFile(String name, String content, boolean external) {
+    String target;
+    if (external) {
+      target = Environment.getExternalStorageDirectory().getAbsolutePath();
+    } else if (getForm().isRepl()) {
+      target = Environment.getExternalStorageDirectory().getAbsolutePath() +
+          "/AppInventor/data";
+    } else {
+      target = getForm().getFilesDir().getAbsolutePath();
+    }
+    target += "/" + name;
+    FileOutputStream out = null;
+    try {
+      java.io.File targetFile = new java.io.File(target);
+      targetFile.deleteOnExit();
+      if (!targetFile.getParentFile().exists()) {
+        if (!targetFile.getParentFile().mkdirs()) {
+          throw new IOException();
+        }
+      }
+      out = new FileOutputStream(target);
+      out.write(content.getBytes(Charset.forName("UTF-8")));
+      return targetFile.getAbsolutePath();
+    } catch (IOException e) {
+      throw new IllegalStateException("Unable to prepare test", e);
+    } finally {
+      IOUtils.closeQuietly(TAG, out);
+    }
+  }
+
+  private void testReadFile(String filename, String expectedData) {
+    file.ReadFrom(filename);
+    ShadowAsynchUtil.runAllPendingRunnables();
+    runAllEvents();
+    ShadowEventDispatcher.assertEventFired(file, "GotText", expectedData);
+  }
+
+}

appinventor/components/tests/com/google/appinventor/components/runtime/FormTest.java

+// -*- mode: java; c-basic-offset: 2; -*-
+// Copyright © 2018 Massachusetts Institute of Technology, All rights reserved.
+// Released under the Apache License, Version 2.0
+// http://www.apache.org/licenses/LICENSE-2.0
+
+package com.google.appinventor.components.runtime;
+
+import com.google.appinventor.components.runtime.test.TestExtension;
+import com.google.appinventor.components.runtime.util.IOUtils;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.Charset;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * Tests for the Form component.
+ *
+ * @author ewpatton@mit.edu (Evan W. Patton)
+ */
+public class FormTest extends RobolectricTestBase {
+
+  private static final int BUFSIZE = 4096;
+  static final String TARGET_FILE = "test.txt";
+
+  /**
+   * Tests the ability of the Form to open an asset.
+   *
+   * @throws IOException if the asset cannot be found.
+   */
+  @Test
+  public void testOpenAsset() throws IOException {
+    InputStream is = null;
+    try {
+      is = getForm().openAsset(TARGET_FILE);
+      assertEquals("Hello, world!\n", readStream(is));
+    } finally {
+      IOUtils.closeQuietly("test", is);
+    }
+  }
+
+  /**
+   * Tests the ability of the Form to open an asset associated with an
+   * extension.
+   *
+   * @throws IOException if the asset cannot be found.
+   */
+  @Test
+  public void testOpenAssetExtension() throws IOException {
+    InputStream is = null;
+    try {
+      is = getForm().openAssetForExtension(new TestExtension(getForm()), TARGET_FILE);
+      assertEquals("Sample extension asset\n", readStream(is));
+    } finally {
+      IOUtils.closeQuietly("test", is);
+    }
+  }
+
+  /// Helper functions
+
+  /**
+   * Read the contents of a stream as a string.
+   *
+   * @param is the input stream to read
+   * @return the contents of the input stream as a string
+   * @throws IOException if the file cannot be read
+   */
+  public static String readStream(InputStream is) throws IOException {
+    byte[] data = new byte[BUFSIZE];
+    int read;
+    StringBuilder sb = new StringBuilder();
+    while ((read = is.read(data, 0, BUFSIZE)) > 0) {
+      sb.append(new String(data, 0, read, Charset.forName("UTF-8")));
+    }
+    return sb.toString();
+  }
+}

appinventor/components/tests/com/google/appinventor/components/runtime/ReplFormTest.java

+// -*- mode: java; c-basic-offset: 2; -*-
+// Copyright © 2018 Massachusetts Institute of Technology, All rights reserved.
+// Released under the Apache License, Version 2.0
+// http://www.apache.org/licenses/LICENSE-2.0
+
+package com.google.appinventor.components.runtime;
+
+import android.Manifest;
+import com.google.appinventor.components.runtime.util.IOUtils;
+import org.junit.Before;
+import org.junit.Test;
+import org.robolectric.Shadows;
+import org.robolectric.shadows.ShadowApplication;
+
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * Tests for the ReplForm.
+ *
+ * @author ewpatton@mit.edu (Evan W. Patton)
+ */
+public class ReplFormTest extends FormTest {
+
+  private static final String TAG = "test";
+  private static final int BUFSIZE = 4096;
+
+  @Before
+  public void setUp() {
+    super.setUpAsRepl();
+    Shadows.shadowOf(getForm()).grantPermissions(Manifest.permission.READ_EXTERNAL_STORAGE);
+    Shadows.shadowOf(getForm()).grantPermissions(Manifest.permission.WRITE_EXTERNAL_STORAGE);
+    copyAssetToReplAssets(TARGET_FILE, TARGET_FILE);
+    copyAssetToReplAssets("com.google.appinventor.components.runtime.test/" + TARGET_FILE,
+        "external_comps/com.google.appinventor.components.runtime.test/assets/" + TARGET_FILE);
+  }
+
+  /**
+   * Test that the form can open naked file paths.
+   *
+   * In version 2.48, ReplForm did not follow the contract for {@link Form#getAssetPath(String)}.
+   * It returned a string containing a file path, not a file URI. This would result in developers
+   * getting an error "URI is not absolute" when live testing. We changed the ReplForm
+   * implementation to behave correctly by returning a string starting with file:///, but we also
+   * test here that we can handle non-URI versions in case someone ends up overriding the method in
+   * a subclass (somehow...).
+   */
+  @Test
+  public void testOpenAssetInternal() throws IOException {
+    InputStream is = null;
+    try {
+      is = getForm().openAssetInternal(ReplForm.REPL_ASSET_DIR + TARGET_FILE);
+      assertEquals("Hello, world!\n", readStream(is));
+    } finally {
+      IOUtils.closeQuietly(TAG, is);
+    }
+  }
+
+  /// Helper functions
+
+  /**
+   * Copy an asset from the given source name to the given target name in the
+   * /sdcard/AppInventor/assets directory.
+   *
+   * @param source the source asset path
+   * @param target the target asset path
+   */
+  public static void copyAssetToReplAssets(String source, String target) {
+    InputStream in = null;
+    OutputStream out = null;
+    try {
+      in = ShadowApplication.getInstance().getApplicationContext().getAssets().open(source);
+      java.io.File targetFile = new java.io.File(ReplForm.REPL_ASSET_DIR + target);
+      if (!targetFile.getParentFile().exists()) {
+        if (!targetFile.getParentFile().mkdirs()) {
+          throw new IllegalStateException("Could not configure REPL assets in setup");
+        }
+      }
+      out = new FileOutputStream(targetFile);
+      byte[] buffer = new byte[BUFSIZE];
+      int bytesRead;
+      while ((bytesRead = in.read(buffer, 0, BUFSIZE)) > 0) {
+        out.write(buffer, 0, bytesRead);
+      }
+    } catch (IOException e) {
+      throw new IllegalStateException("Could not configure REPL assets in test setup", e);
+    } finally {
+      IOUtils.closeQuietly(TAG, in);
+      IOUtils.closeQuietly(TAG, out);
+    }
+  }
+
+}

appinventor/components/tests/com/google/appinventor/components/runtime/RobolectricTestBase.java

@@ -28,7 +28,7 @@ import java.util.concurrent.TimeUnit;
  * @author ewpatton@mit.edu (Evan W. Patton)
  */
 @RunWith(RobolectricTestRunner.class)
-@Config(sdk = 22, manifest="tests/AndroidManifest.xml",
+@Config(sdk = 23, manifest="tests/AndroidManifest.xml",
     shadows = {ShadowStorageUtils.class, ShadowEventDispatcher.class, ShadowAsynchUtil.class})
 public class RobolectricTestBase {
 
@@ -45,14 +45,33 @@ public class RobolectricTestBase {
     }
   }
 
+  private static class FakeReplForm extends ReplForm {
+    @Override
+    protected void $define() {}
+
+    @Override
+    public void dispatchErrorOccurredEvent(Component component, String functionName, int errorCode, Object... args) {
+      String message = ErrorMessages.formatMessage(errorCode, args);
+      ShadowEventDispatcher.dispatchEvent(this.$form(), "ErrorOccurred", component, functionName, errorCode, message);
+    }
+  }
+
   public Form getForm() {
     return form;
   }
 
   @Before
   public void setUp() {
+    setUpForm(FakeForm.class);
+  }
+
+  public void setUpAsRepl() {
+    setUpForm(FakeReplForm.class);
+  }
+
+  private <T extends Form> void setUpForm(Class<T> clazz) {
     ShadowLooper.getShadowMainLooper().getScheduler().setIdleState(IdleState.PAUSED);
-    ActivityController<FakeForm> activityController = Robolectric.buildActivity(FakeForm.class)
+    ActivityController<T> activityController = Robolectric.buildActivity(clazz)
         .create().start().resume().visible();
     form = activityController.get();
     // Unfortunately Robolectric won't handle laying out the view hierarchy and because of how

appinventor/components/tests/com/google/appinventor/components/runtime/repltest/FileReplTest.java

+// -*- mode: java; c-basic-offset: 2; -*-
+// Copyright © 2018 Massachusetts Institute of Technology, All rights reserved.
+// Released under the Apache License, Version 2.0
+// http://www.apache.org/licenses/LICENSE-2.0
+
+package com.google.appinventor.components.runtime.repltest;
+
+import com.google.appinventor.components.runtime.File;
+import com.google.appinventor.components.runtime.FileTest;
+import com.google.appinventor.components.runtime.ReplFormTest;
+import org.junit.Before;
+
+/**
+ * Tests for the File Component, but run as if it is in the REPL rather than
+ * in a compiled application. See {@link FileTest} for the test definitions.
+ *
+ * @author ewpatton@mit.edu (Evan W. Patton)
+ */
+public class FileReplTest extends FileTest {
+  @Before
+  public void setUp() {
+    setUpAsRepl();
+    file = new File(getForm());
+    ReplFormTest.copyAssetToReplAssets(TARGET_FILE, TARGET_FILE);
+  }
+}

appinventor/components/tests/com/google/appinventor/components/runtime/shadows/ShadowActivityCompat.java

+// -*- mode: java; c-basic-offset: 2; -*-
+// Copyright © 2018 Massachusetts Institute of Technology, All rights reserved.
+// Released under the Apache License, Version 2.0
+// http://www.apache.org/licenses/LICENSE-2.0
+
+package com.google.appinventor.components.runtime.shadows;
+
+import android.app.Activity;
+import android.content.pm.PackageManager;
+import android.support.v4.app.ActivityCompat;
+import org.robolectric.annotation.Implementation;
+import org.robolectric.annotation.Implements;
+
+/**
+ * A shadow implementation of ActivityCompat that allows one to
+ * grant/deny permissions requested when the app calls
+ * {@link ActivityCompat#requestPermission(Activity,String,String)}.
+ *
+ * @author ewpatton@mit.edu (Evan W. Patton)
+ */
+@Implements(ActivityCompat.class)
+public class ShadowActivityCompat {
+
+  private static Activity activity;
+  private static String[] permissions;
+  private static int requestCode;
+
+  @Implementation
+  public static void requestPermissions(final Activity activity, final String[] permissions, final int requestCode) {
+    ShadowActivityCompat.activity = activity;
+    ShadowActivityCompat.permissions = permissions;
+    ShadowActivityCompat.requestCode = requestCode;
+  }
+
+  /**
+   * Grants the last set of permissions requested by the app.
+   */
+  public static void grantLastRequestedPermissions() {
+    int[] result = new int[permissions.length];
+    for (int i = 0; i < result.length; i++) {
+      result[i] = PackageManager.PERMISSION_GRANTED;
+    }
+    activity.onRequestPermissionsResult(requestCode, permissions, result);
+  }
+
+  /**
+   * Denies the last set of permissions requested by the app.
+   */
+  public static void denyLastRequestedPermissions() {
+    int[] result = new int[permissions.length];
+    for (int i = 0; i < result.length; i++) {
+      result[i] = PackageManager.PERMISSION_DENIED;
+    }
+    activity.onRequestPermissionsResult(requestCode, permissions, result);
+  }
+}

appinventor/components/tests/com/google/appinventor/components/runtime/shadows/ShadowEventDispatcher.java

 // -*- mode: java; c-basic-offset: 2; -*-
-// Copyright © 2017 Massachusetts Institute of Technology, All rights reserved.
+// Copyright © 2017-2018 Massachusetts Institute of Technology, All rights reserved.
 // Released under the Apache License, Version 2.0
 // http://www.apache.org/licenses/LICENSE-2.0
 
@@ -111,4 +111,23 @@ public class ShadowEventDispatcher {
     }
     throw new AssertionError(String.format("Form did not receive ErrorOccurred event with code %d.", errorCode));
   }
+
+  /**
+   * Asserts that the EventDispatcher saw a PermissionDenied event for the given permission name.
+   *
+   * @param permission the permission to test for denial
+   */
+  public static void assertPermissionDenied(String permission) {
+    if (permission.startsWith("android.permission.")) {
+      permission = permission.replace("android.permission.", "");
+    }
+    for (Set<EventWithArgs> events: firedEvents.values()) {
+      for (EventWithArgs event : events) {
+        if ("PermissionDenied".equals(event.eventName) && event.args[2].equals(permission)) {
+          return;
+        }
+      }
+    }
+    throw new AssertionError(String.format("Form did not receive PermissionDenied event for permission %s.", permission));
+  }
 }

appinventor/components/tests/com/google/appinventor/components/runtime/test/TestExtension.java

+// -*- mode: java; c-basic-offset: 2; -*-
+// Copyright © 2018 Massachusetts Institute of Technology, All rights reserved.
+// Released under the Apache License, Version 2.0
+// http://www.apache.org/licenses/LICENSE-2.0
+
+package com.google.appinventor.components.runtime.test;
+
+import com.google.appinventor.components.annotations.SimpleObject;
+import com.google.appinventor.components.runtime.AndroidNonvisibleComponent;
+import com.google.appinventor.components.runtime.Form;
+
+/**
+ * TestExtension is a barebones extension class that can be used for testing
+ * different features of the App Inventor extensions mechanism in the REPL.
+ *
+ * @author ewpatton@mit.edu (Evan W. Patton)
+ */
+@SimpleObject(external = true)
+public class TestExtension extends AndroidNonvisibleComponent {
+  public TestExtension(Form form) {
+    super(form);
+  }
+}