[android] add unit tests for #13947

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/storage/FileSource.java

@@ -231,7 +231,7 @@ protected void onPostExecute(String[] paths) {
    * @param context the context to derive the files directory path from
    * @return the files directory path
    */
-  @Nullable
+  @NonNull
   public static String getResourcesCachePath(@NonNull Context context) {
     resourcesCachePathLoaderLock.lock();
     try {

platform/android/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/storage/FileSourceMapTest.kt

@@ -0,0 +1,58 @@
+package com.mapbox.mapboxsdk.testapp.storage
+
+import android.support.test.annotation.UiThreadTest
+import android.support.test.rule.ActivityTestRule
+import android.support.test.runner.AndroidJUnit4
+import com.mapbox.mapboxsdk.storage.FileSource
+import com.mapbox.mapboxsdk.testapp.activity.espresso.EspressoTestActivity
+import junit.framework.Assert
+import org.junit.After
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.junit.rules.TestName
+import org.junit.runner.RunWith
+import java.util.concurrent.CountDownLatch
+
+@RunWith(AndroidJUnit4::class)
+open class FileSourceMapTest {
+
+  private lateinit var fileSourceTestUtils: FileSourceTestUtils
+
+  @get:Rule
+  val rule = ActivityTestRule(EspressoTestActivity::class.java)
+
+  @get:Rule
+  val testName = TestName()
+
+  @Before
+  @UiThreadTest
+  fun setup() {
+    fileSourceTestUtils = FileSourceTestUtils(rule.activity)
+    fileSourceTestUtils.setup()
+  }
+
+  @Test
+  fun changeResourcesPathWhileMapVisible() {
+    val latch = CountDownLatch(1)
+    rule.activity.runOnUiThread {
+      FileSource.setResourcesCachePath(rule.activity, fileSourceTestUtils.testPath, object : FileSource.ResourcesCachePathChangeCallback {
+        override fun onSuccess(path: String?) {
+          Assert.fail("Requested resources change while the map is running should fail")
+        }
+
+        override fun onError(message: String?) {
+          Assert.assertEquals("Cannot set path, file source is activated."
+            + " Make sure that the map or a resources download is not running.", message)
+          latch.countDown()
+        }
+      })
+    }
+    latch.await()
+  }
+
+  @After
+  fun cleanup() {
+    fileSourceTestUtils.cleanup()
+  }
+}

platform/android/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/storage/FileSourceStandaloneTest.kt

@@ -0,0 +1,77 @@
+package com.mapbox.mapboxsdk.testapp.storage
+
+import android.os.Handler
+import android.support.test.annotation.UiThreadTest
+import android.support.test.rule.ActivityTestRule
+import android.support.test.runner.AndroidJUnit4
+import com.mapbox.mapboxsdk.storage.FileSource
+import com.mapbox.mapboxsdk.testapp.activity.FeatureOverviewActivity
+import org.junit.*
+import org.junit.rules.TestName
+import org.junit.runner.RunWith
+import java.util.concurrent.CountDownLatch
+
+@RunWith(AndroidJUnit4::class)
+class FileSourceStandaloneTest {
+
+  private lateinit var fileSourceTestUtils: FileSourceTestUtils
+  private lateinit var fileSource: FileSource
+
+  @get:Rule
+  val rule = ActivityTestRule(FeatureOverviewActivity::class.java)
+
+  @get:Rule
+  val testName = TestName()
+
+  @Before
+  @UiThreadTest
+  fun setup() {
+    fileSource = FileSource.getInstance(rule.activity)
+    fileSourceTestUtils = FileSourceTestUtils(rule.activity)
+    fileSourceTestUtils.setup()
+  }
+
+  @Test
+  @UiThreadTest
+  fun testDefault() {
+    Assert.assertFalse("FileSource should not be active", fileSource.isActivated)
+  }
+
+  @Test
+  @UiThreadTest
+  fun testActivateDeactivate() {
+    Assert.assertFalse("1) FileSource should not be active", fileSource.isActivated)
+    fileSource.activate()
+    Assert.assertTrue("2) FileSource should be active", fileSource.isActivated)
+    fileSource.deactivate()
+    Assert.assertFalse("3) FileSource should not be active", fileSource.isActivated)
+  }
+
+  @Test
+  fun pathChangeTest() {
+    Assert.assertFalse("FileSource should not be active", fileSource.isActivated)
+    Assert.assertEquals(fileSourceTestUtils.originalPath, FileSource.getResourcesCachePath(rule.activity))
+
+    fileSourceTestUtils.changePath(fileSourceTestUtils.testPath)
+    Assert.assertEquals(fileSourceTestUtils.testPath, FileSource.getResourcesCachePath(rule.activity))
+
+    // workaround for https://github.com/mapbox/mapbox-gl-native/issues/14334
+    val latch = CountDownLatch(1)
+    rule.activity.runOnUiThread {
+      fileSource.activate()
+      Handler().postDelayed({
+        fileSource.deactivate()
+        latch.countDown()
+      }, 2000)
+    }
+    latch.await()
+
+    fileSourceTestUtils.changePath(fileSourceTestUtils.originalPath)
+    Assert.assertEquals(fileSourceTestUtils.originalPath, FileSource.getResourcesCachePath(rule.activity))
+  }
+
+  @After
+  fun cleanup() {
+    fileSourceTestUtils.cleanup()
+  }
+}

platform/android/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/storage/FileSourceTestUtils.kt

@@ -0,0 +1,50 @@
+package com.mapbox.mapboxsdk.testapp.storage
+
+import android.app.Activity
+import android.support.annotation.WorkerThread
+import com.mapbox.mapboxsdk.storage.FileSource
+import junit.framework.Assert
+import java.io.File
+import java.util.concurrent.CountDownLatch
+
+class FileSourceTestUtils(private val activity: Activity) {
+  val originalPath = FileSource.getResourcesCachePath(activity)
+  val testPath = "$originalPath/test"
+
+  fun setup() {
+    val testFile = File(testPath)
+    testFile.mkdirs()
+  }
+
+  @WorkerThread
+  fun cleanup() {
+    val currentPath = FileSource.getResourcesCachePath(activity)
+    if (currentPath != originalPath) {
+      changePath(originalPath)
+    }
+    val testFile = File(testPath)
+    if (testFile.exists()) {
+      testFile.deleteRecursively()
+    }
+  }
+
+  @WorkerThread
+  fun changePath(path: String) {
+    val latch = CountDownLatch(1)
+    activity.runOnUiThread {
+      FileSource.setResourcesCachePath(
+        activity,
+        path,
+        object : FileSource.ResourcesCachePathChangeCallback {
+          override fun onSuccess(path: String?) {
+            latch.countDown()
+          }
+
+          override fun onError(message: String?) {
+            Assert.fail("Resource path change failed - path: $path, message: $message")
+          }
+        })
+    }
+    latch.await()
+  }
+}