[Widget] Added unit tests and instrumentation tests to the Widget Sam…

…ple (#40)

* [Widget] Added unit tests and instrumentation tests to the Widget Sample, split logic from network and parsing

- Refactored tasks.withType(KotlinCompile) to be included in allprojects so it will work also for tests
- Separated the networking logic from the parsing logic using NetworkFeed object
- Moved rssItems data to the WidgetFactory to use the object's methods just as helper functions
- Created a BaseSimpleApi interface so RssSimpleApi can be mocked with a test api
- Fixed stripHtml special character regex
- Added unit tests for networking logic with a mocked web server
- Added UI tests for the changing the feed url
- Added instrumentation tests for the xml parsing

Widget/app/build.gradle

@@ -31,6 +31,8 @@ dependencies {
     implementation networkDependencies.okhttpLoggingInterceptor
 
     testImplementation testDependencies.junit
+    testImplementation testDependencies.mockWebServer
     androidTestImplementation instrumentationTestDependencies.junit
     androidTestImplementation instrumentationTestDependencies.espressoCore
+    androidTestImplementation instrumentationTestDependencies.testRules
 }

Widget/app/src/androidTest/java/com/microsoft/device/display/samples/widget/SettingsUrlTest.kt

@@ -0,0 +1,76 @@
+/*
+ *
+ * Copyright (c) Microsoft Corporation. All rights reserved.
+ * Licensed under the MIT License.
+ *
+ */
+
+package com.microsoft.device.display.samples.widget
+
+import androidx.preference.PreferenceManager
+import androidx.test.espresso.Espresso.onView
+import androidx.test.espresso.action.ViewActions.click
+import androidx.test.espresso.assertion.ViewAssertions.matches
+import androidx.test.espresso.matcher.ViewMatchers.isDisplayed
+import androidx.test.espresso.matcher.ViewMatchers.withText
+import androidx.test.filters.MediumTest
+import androidx.test.internal.runner.junit4.AndroidJUnit4ClassRunner
+import androidx.test.platform.app.InstrumentationRegistry
+import androidx.test.rule.ActivityTestRule
+import com.microsoft.device.display.samples.widget.feed.RssFeed.DEFAULT_FEED_URL
+import com.microsoft.device.display.samples.widget.settings.SettingsActivity
+import org.junit.Assert.assertEquals
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(AndroidJUnit4ClassRunner::class)
+@MediumTest
+class SettingsUrlTest {
+
+    @get:Rule
+    val activityRule = ActivityTestRule<SettingsActivity>(SettingsActivity::class.java)
+
+    private val appContext = InstrumentationRegistry.getInstrumentation().targetContext
+
+    @Before
+    fun clearPreferences() {
+        PreferenceManager.getDefaultSharedPreferences(appContext).edit().clear().commit()
+    }
+
+    @Test
+    fun shouldBeDefaultFeedUrl_whenGettingRequestUrlFromPreferences() {
+        assertEquals(
+            "Preferences Feed Url should be Default Feed Url",
+            DEFAULT_FEED_URL,
+            getUrlFromPreferences()
+        )
+    }
+
+    @Test
+    fun shouldSavePreference_whenAnotherFeedUrlIsChosen() {
+        onView(withText(R.string.widget_settings_predefined_title)).check(matches(isDisplayed()))
+        onView(withText(R.string.widget_settings_custom_title)).check(matches(isDisplayed()))
+
+        onView(withText(R.string.widget_settings_predefined_title)).perform(click())
+
+        val secondKey = appContext.resources.getStringArray(R.array.appwidget_feeds)[1]
+        val secondValue = appContext.resources.getStringArray(R.array.appwidget_feeds_value)[1]
+        onView(withText(secondKey)).perform(click())
+
+        assertEquals(
+            "Preferences Feed Url should be second value url",
+            secondValue,
+            getUrlFromPreferences()
+        )
+    }
+
+    private fun getUrlFromPreferences(): String? {
+        val preferences = PreferenceManager.getDefaultSharedPreferences(appContext)
+        return preferences.getString(
+            appContext.resources.getString(R.string.widget_settings_predefined_key),
+            DEFAULT_FEED_URL
+        )
+    }
+}

Widget/app/src/androidTest/java/com/microsoft/device/display/samples/widget/XmlParserRssFeedTest.kt

@@ -0,0 +1,261 @@
+/*
+ *
+ * Copyright (c) Microsoft Corporation. All rights reserved.
+ * Licensed under the MIT License.
+ *
+ */
+
+package com.microsoft.device.display.samples.widget
+
+import androidx.test.filters.MediumTest
+import androidx.test.internal.runner.junit4.AndroidJUnit4ClassRunner
+import com.microsoft.device.display.samples.widget.feed.RssFeed
+import com.microsoft.device.display.samples.widget.feed.RssFeed.CHANNEL
+import com.microsoft.device.display.samples.widget.feed.RssFeed.CREATOR
+import com.microsoft.device.display.samples.widget.feed.RssFeed.DESCRIPTION
+import com.microsoft.device.display.samples.widget.feed.RssFeed.ITEM
+import com.microsoft.device.display.samples.widget.feed.RssFeed.LINK
+import com.microsoft.device.display.samples.widget.feed.RssFeed.PUB_DATE
+import com.microsoft.device.display.samples.widget.feed.RssFeed.TITLE
+import com.microsoft.device.display.samples.widget.feed.RssItem
+import org.hamcrest.MatcherAssert.assertThat
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotNull
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.hamcrest.Matchers.`is` as iz
+
+@RunWith(AndroidJUnit4ClassRunner::class)
+@MediumTest
+class XmlParserRssFeedTest {
+
+    @Test
+    fun parseXml_shouldReturnEmptyList_whenNoRssItemsFound() {
+        val xmlString =
+            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<rss version=\"2.0\">" +
+                "    <$CHANNEL></$CHANNEL>" +
+                "</rss>"
+
+        val rssItems = RssFeed.parseXml(xmlString)
+        assertThat(
+            "Method should return empty list if item tag is not found in xml",
+            rssItems,
+            iz(emptyList())
+        )
+    }
+
+    @Test
+    fun parseXml_shouldReturnOneElementList_whenOneRssItemFound() {
+        val xmlString =
+            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<rss version=\"2.0\">" +
+                "    <$CHANNEL>\n" +
+                "        <$ITEM></$ITEM>\n" +
+                "    </$CHANNEL>" +
+                "</rss>"
+
+        val emptyRssItem = RssItem(null, null, null, null, null)
+        val rssItems = RssFeed.parseXml(xmlString)
+
+        assertEquals(
+            "Method should return list containing one element if one item tag is found",
+            1,
+            rssItems.size
+        )
+
+        assertEquals(
+            "Rss Item should be empty when only item tag is encountered",
+            emptyRssItem,
+            rssItems[0]
+        )
+    }
+
+    @Test
+    fun parseXml_shouldReturnEmptyList_whenItemTagIsLonger() {
+        val xmlString =
+            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<rss version=\"2.0\">" +
+                "    <$CHANNEL>\n" +
+                "        <$ITEM$ITEM></$ITEM$ITEM>\n" +
+                "    </$CHANNEL>" +
+                "</rss>"
+
+        val rssItems = RssFeed.parseXml(xmlString)
+        assertThat(
+            "Method should return empty list if item tag name in xml is longer",
+            rssItems,
+            iz(emptyList())
+        )
+    }
+
+    @Test
+    fun parseXml_shouldContainElementWithTitle_whenItemHasTitle() {
+        val expectedTitle = "Build and test dual-screen web apps"
+        val xmlString =
+            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<rss version=\"2.0\">" +
+                "    <$CHANNEL>\n" +
+                "        <$ITEM>\n" +
+                "            <$TITLE>$expectedTitle</$TITLE>\n" +
+                "        </$ITEM>\n" +
+                "    </$CHANNEL>" +
+                "</rss>"
+
+        val rssItem = RssFeed.parseXml(xmlString)[0]
+
+        assertNotNull(
+            "Rss Item should not have null title",
+            rssItem?.title
+        )
+
+        assertEquals(
+            "Rss Item should have title = $expectedTitle",
+            expectedTitle,
+            rssItem?.title
+        )
+    }
+
+    @Test
+    fun parseXml_shouldContainElementWithCreator_whenItemHasCreator() {
+        val expectedCreator = "Craig Dunn"
+        val xmlString =
+            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<rss version=\"2.0\">" +
+                "    <$CHANNEL>\n" +
+                "        <$ITEM>\n" +
+                "            <$CREATOR><![CDATA[$expectedCreator]]></$CREATOR>\n" +
+                "        </$ITEM>\n" +
+                "    </$CHANNEL>" +
+                "</rss>"
+
+        val rssItem = RssFeed.parseXml(xmlString)[0]
+
+        assertNotNull(
+            "Rss Item should not have null creator",
+            rssItem?.creator
+        )
+
+        assertEquals(
+            "Rss Item should have creator = $expectedCreator",
+            expectedCreator,
+            rssItem?.creator
+        )
+    }
+
+    @Test
+    fun parseXml_shouldContainElementWithDate_whenItemHasDate() {
+        val expectedDate = "Thu, 03 Sep 2020 21:17:19"
+        val actualDate = "Thu, 03 Sep 2020 21:17:19 +0000"
+        val xmlString =
+            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<rss version=\"2.0\">" +
+                "    <$CHANNEL>\n" +
+                "        <$ITEM>\n" +
+                "            <$PUB_DATE>$actualDate</$PUB_DATE>\n" +
+                "        </$ITEM>\n" +
+                "    </$CHANNEL>" +
+                "</rss>"
+
+        val rssItem = RssFeed.parseXml(xmlString)[0]
+
+        assertNotNull(
+            "Rss Item should not have null date",
+            rssItem?.date
+        )
+
+        assertEquals(
+            "Rss Item should have date = $expectedDate",
+            expectedDate,
+            rssItem?.date
+        )
+    }
+
+    @Test
+    fun parseXml_shouldContainElementWithLink_whenItemHasLink() {
+        val expectedLink = "https://devblogs.microsoft.com/surface-duo/build-and-test-dual-screen-web-apps/"
+        val xmlString =
+            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<rss version=\"2.0\">" +
+                "    <$CHANNEL>\n" +
+                "        <$ITEM>\n" +
+                "            <$LINK>$expectedLink</$LINK>\n" +
+                "        </$ITEM>\n" +
+                "    </$CHANNEL>" +
+                "</rss>"
+
+        val rssItem = RssFeed.parseXml(xmlString)[0]
+
+        assertNotNull(
+            "Rss Item should not have null href",
+            rssItem?.href
+        )
+
+        assertEquals(
+            "Rss Item should have href = $expectedLink",
+            expectedLink,
+            rssItem?.href
+        )
+    }
+
+    @Test
+    fun parseXml_shouldContainElementWithDescription_whenItemHasShortDescription() {
+        val actualDescription = "Hello dual-screen web developers! This is the day"
+        val expectedDescription = "Hello dual-screen web developers! This is the day..."
+        val xmlString =
+            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<rss version=\"2.0\">" +
+                "    <$CHANNEL>\n" +
+                "        <$ITEM>\n" +
+                "            <$DESCRIPTION>$actualDescription</$DESCRIPTION>\n" +
+                "        </$ITEM>\n" +
+                "    </$CHANNEL>" +
+                "</rss>"
+
+        val rssItem = RssFeed.parseXml(xmlString)[0]
+
+        assertNotNull(
+            "Rss Item should not have null body",
+            rssItem?.body
+        )
+
+        assertEquals(
+            "Rss Item should have body = $expectedDescription",
+            expectedDescription,
+            rssItem?.body
+        )
+    }
+
+    @Test
+    fun parseXml_shouldContainElementWithDescription_whenItemHasLongDescription() {
+        val builder = StringBuilder()
+        for (index in 0 until RssFeed.DESCRIPTION_MAX_CHARS) {
+            builder.append("a")
+        }
+        val expectedDescription = builder.append("...").toString()
+        val actualDescription = expectedDescription + "description"
+
+        val xmlString =
+            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<rss version=\"2.0\">" +
+                "    <$CHANNEL>\n" +
+                "        <$ITEM>\n" +
+                "            <$DESCRIPTION>$actualDescription</$DESCRIPTION>\n" +
+                "        </$ITEM>\n" +
+                "    </$CHANNEL>" +
+                "</rss>"
+
+        val rssItem = RssFeed.parseXml(xmlString)[0]
+
+        assertNotNull(
+            "Rss Item should not have null body",
+            rssItem?.body
+        )
+
+        assertEquals(
+            "Rss Item should have body = $expectedDescription",
+            expectedDescription,
+            rssItem?.body
+        )
+    }
+}

Widget/app/src/main/java/com/microsoft/device/display/samples/widget/WidgetApp.kt

@@ -78,7 +78,7 @@ class WidgetApp : AppWidgetProvider() {
 
     override fun onReceive(context: Context, intent: Intent) {
         // Handling intent for list item click
-        if (WidgetFactory.ACTION_INTENT_VIEW_TAG.equals(intent.action)) {
+        if (WidgetFactory.ACTION_INTENT_VIEW_TAG == intent.action) {
             val url =
                 intent.getStringExtra(WidgetFactory.ACTION_INTENT_VIEW_HREF_TAG)
             val webIntent = Intent(Intent.ACTION_VIEW, Uri.parse(url))