Add Compose UI tests covering ErrorPanel and comment section flows

app/build.gradle

@@ -342,6 +342,10 @@ dependencies {
     androidTestImplementation libs.androidx.runner
     androidTestImplementation libs.androidx.room.testing
     androidTestImplementation libs.assertj.core
+    androidTestImplementation platform(libs.androidx.compose.bom)
+    androidTestImplementation libs.androidx.compose.ui.test.junit4
+    debugImplementation libs.androidx.compose.ui.test.manifest
+
 }
 
 static String getGitWorkingBranch() {

app/src/androidTest/java/org/schabi/newpipe/error/ErrorInfoCommentsTest.kt

@@ -1,59 +0,0 @@
-package org.schabi.newpipe.error
-
-import android.content.Context
-import androidx.test.core.app.ApplicationProvider
-import androidx.test.ext.junit.runners.AndroidJUnit4
-import org.junit.Assert
-import org.junit.Test
-import org.junit.runner.RunWith
-import org.schabi.newpipe.R
-import org.schabi.newpipe.extractor.exceptions.ReCaptchaException
-import java.io.IOException
-import java.net.SocketTimeoutException
-
-@RunWith(AndroidJUnit4::class)
-class ErrorInfoCommentsTest {
-    private val context: Context by lazy { ApplicationProvider.getApplicationContext<Context>() }
-    // Test 1: Network error on initial load (Resource.Error)
-    @Test
-    fun testInitialCommentNetworkError() {
-        val errorInfo = ErrorInfo(
-            throwable = SocketTimeoutException("Connection timeout"),
-            userAction = UserAction.REQUESTED_COMMENTS,
-            request = "comments"
-        )
-        Assert.assertEquals(context.getString(R.string.network_error), errorInfo.getMessage(context))
-        Assert.assertTrue(errorInfo.isReportable)
-        Assert.assertTrue(errorInfo.isRetryable)
-        Assert.assertNull(errorInfo.recaptchaUrl)
-    }
-
-    // Test 2: Network error on paging (LoadState.Error)
-    @Test
-    fun testPagingNetworkError() {
-        val errorInfo = ErrorInfo(
-            throwable = IOException("Paging failed"),
-            userAction = UserAction.REQUESTED_COMMENTS,
-            request = "comments"
-        )
-        Assert.assertEquals(context.getString(R.string.network_error), errorInfo.getMessage(context))
-        Assert.assertTrue(errorInfo.isReportable)
-        Assert.assertTrue(errorInfo.isRetryable)
-        Assert.assertNull(errorInfo.recaptchaUrl)
-    }
-
-    // Test 3: ReCaptcha during comments load
-    @Test
-    fun testReCaptchaDuringComments() {
-        val url = "https://www.google.com/recaptcha/api/fallback?k=test"
-        val errorInfo = ErrorInfo(
-            throwable = ReCaptchaException("ReCaptcha needed", url),
-            userAction = UserAction.REQUESTED_COMMENTS,
-            request = "comments"
-        )
-        Assert.assertEquals(context.getString(R.string.recaptcha_request_toast), errorInfo.getMessage(context))
-        Assert.assertEquals(url, errorInfo.recaptchaUrl)
-        Assert.assertFalse(errorInfo.isReportable)
-        Assert.assertTrue(errorInfo.isRetryable)
-    }
-}

app/src/androidTest/java/org/schabi/newpipe/error/ErrorInfoTest.java

@@ -1,62 +0,0 @@
-package org.schabi.newpipe.error;
-
-import android.os.Parcel;
-
-import androidx.test.ext.junit.runners.AndroidJUnit4;
-import androidx.test.filters.LargeTest;
-
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.schabi.newpipe.R;
-import org.schabi.newpipe.extractor.ServiceList;
-import org.schabi.newpipe.extractor.exceptions.ParsingException;
-
-import java.util.Arrays;
-import java.util.Objects;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-
-/**
- * Instrumented tests for {@link ErrorInfo}.
- */
-@RunWith(AndroidJUnit4.class)
-@LargeTest
-public class ErrorInfoTest {
-
-    /**
-     * @param errorInfo the error info to access
-     * @return the private field errorInfo.message.stringRes using reflection
-     */
-    private int getMessageFromErrorInfo(final ErrorInfo errorInfo)
-            throws NoSuchFieldException, IllegalAccessException {
-        final var message = ErrorInfo.class.getDeclaredField("message");
-        message.setAccessible(true);
-        final var messageValue = (ErrorInfo.Companion.ErrorMessage) message.get(errorInfo);
-
-        final var stringRes = ErrorInfo.Companion.ErrorMessage.class.getDeclaredField("stringRes");
-        stringRes.setAccessible(true);
-        return (int) Objects.requireNonNull(stringRes.get(messageValue));
-    }
-
-    @Test
-    public void errorInfoTestParcelable() throws NoSuchFieldException, IllegalAccessException {
-        final ErrorInfo info = new ErrorInfo(new ParsingException("Hello"),
-                UserAction.USER_REPORT, "request", ServiceList.YouTube.getServiceId());
-        // Obtain a Parcel object and write the parcelable object to it:
-        final Parcel parcel = Parcel.obtain();
-        info.writeToParcel(parcel, 0);
-        parcel.setDataPosition(0);
-        final ErrorInfo infoFromParcel = (ErrorInfo) ErrorInfo.CREATOR.createFromParcel(parcel);
-
-        assertTrue(Arrays.toString(infoFromParcel.getStackTraces())
-                .contains(ErrorInfoTest.class.getSimpleName()));
-        assertEquals(UserAction.USER_REPORT, infoFromParcel.getUserAction());
-        assertEquals(ServiceList.YouTube.getServiceInfo().getName(),
-                infoFromParcel.getServiceName());
-        assertEquals("request", infoFromParcel.getRequest());
-        assertEquals(R.string.parsing_error, getMessageFromErrorInfo(infoFromParcel));
-
-        parcel.recycle();
-    }
-}

app/src/androidTest/java/org/schabi/newpipe/error/ErrorInfoTest.kt

@@ -0,0 +1,128 @@
+package org.schabi.newpipe.error
+
+import android.content.Context
+import android.os.Parcel
+import android.os.Parcelable
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.filters.LargeTest
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.schabi.newpipe.R
+import org.schabi.newpipe.extractor.ServiceList
+import org.schabi.newpipe.extractor.exceptions.ParsingException
+import org.schabi.newpipe.extractor.exceptions.ReCaptchaException
+import java.io.IOException
+import java.net.SocketTimeoutException
+
+/**
+ * Instrumented tests for {@link ErrorInfo}.
+ */
+@RunWith(AndroidJUnit4::class)
+@LargeTest
+class ErrorInfoTest {
+    private val context: Context by lazy { ApplicationProvider.getApplicationContext<Context>() }
+
+    /**
+     * @param errorInfo the error info to access
+     * @return the private field errorInfo.message.stringRes using reflection
+     */
+    @Throws(NoSuchFieldException::class, IllegalAccessException::class)
+    private fun getMessageFromErrorInfo(errorInfo: ErrorInfo): Int {
+        val message = ErrorInfo::class.java.getDeclaredField("message")
+        message.isAccessible = true
+        val messageValue = message.get(errorInfo) as ErrorInfo.Companion.ErrorMessage
+
+        val stringRes = ErrorInfo.Companion.ErrorMessage::class.java.getDeclaredField("stringRes")
+        stringRes.isAccessible = true
+        return stringRes.get(messageValue) as Int
+    }
+
+    @Test
+    @Throws(NoSuchFieldException::class, IllegalAccessException::class)
+    fun errorInfoTestParcelable() {
+        val info = ErrorInfo(
+            ParsingException("Hello"),
+            UserAction.USER_REPORT,
+            "request",
+            ServiceList.YouTube.serviceId
+        )
+        // Obtain a Parcel object and write the parcelable object to it:
+        val parcel = Parcel.obtain()
+        info.writeToParcel(parcel, 0)
+        parcel.setDataPosition(0)
+        val creatorField = ErrorInfo::class.java.getDeclaredField("CREATOR")
+        val creator = creatorField.get(null)
+        check(creator is Parcelable.Creator<*>)
+        val infoFromParcel = requireNotNull(
+            creator.createFromParcel(parcel) as? ErrorInfo
+        )
+        assertTrue(
+            infoFromParcel.stackTraces.contentToString()
+                .contains(ErrorInfoTest::class.java.simpleName)
+        )
+        assertEquals(UserAction.USER_REPORT, infoFromParcel.userAction)
+        assertEquals(
+            ServiceList.YouTube.serviceInfo.name,
+            infoFromParcel.getServiceName()
+        )
+        assertEquals("request", infoFromParcel.request)
+        assertEquals(R.string.parsing_error, getMessageFromErrorInfo(infoFromParcel))
+
+        parcel.recycle()
+    }
+
+    /**
+     * Test: Network error on initial load (Resource.Error)
+     */
+
+    @Test
+    fun testInitialCommentNetworkError() {
+        val errorInfo = ErrorInfo(
+            throwable = SocketTimeoutException("Connection timeout"),
+            userAction = UserAction.REQUESTED_COMMENTS,
+            request = "comments"
+        )
+        assertEquals(context.getString(R.string.network_error), errorInfo.getMessage(context))
+        assertTrue(errorInfo.isReportable)
+        assertTrue(errorInfo.isRetryable)
+        assertNull(errorInfo.recaptchaUrl)
+    }
+
+    /**
+     * Test: Network error on paging (LoadState.Error)
+     */
+    @Test
+    fun testPagingNetworkError() {
+        val errorInfo = ErrorInfo(
+            throwable = IOException("Paging failed"),
+            userAction = UserAction.REQUESTED_COMMENTS,
+            request = "comments"
+        )
+        assertEquals(context.getString(R.string.network_error), errorInfo.getMessage(context))
+        assertTrue(errorInfo.isReportable)
+        assertTrue(errorInfo.isRetryable)
+        assertNull(errorInfo.recaptchaUrl)
+    }
+
+    /**
+     * Test: ReCaptcha during comments load
+     */
+    @Test
+    fun testReCaptchaDuringComments() {
+        val url = "https://www.google.com/recaptcha/api/fallback?k=test"
+        val errorInfo = ErrorInfo(
+            throwable = ReCaptchaException("ReCaptcha needed", url),
+            userAction = UserAction.REQUESTED_COMMENTS,
+            request = "comments"
+        )
+        assertEquals(context.getString(R.string.recaptcha_request_toast), errorInfo.getMessage(context))
+        assertEquals(url, errorInfo.recaptchaUrl)
+        assertFalse(errorInfo.isReportable)
+        assertTrue(errorInfo.isRetryable)
+    }
+}

app/src/androidTest/java/org/schabi/newpipe/ui/components/common/ErrorPanelTest.kt

@@ -0,0 +1,126 @@
+package org.schabi.newpipe.ui.components.common
+
+import androidx.activity.ComponentActivity
+import androidx.annotation.StringRes
+import androidx.compose.ui.test.assertIsDisplayed
+import androidx.compose.ui.test.junit4.createAndroidComposeRule
+import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.test.performClick
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.schabi.newpipe.R
+import org.schabi.newpipe.error.ErrorInfo
+import org.schabi.newpipe.error.UserAction
+import org.schabi.newpipe.extractor.exceptions.ContentNotAvailableException
+import org.schabi.newpipe.extractor.exceptions.ReCaptchaException
+import org.schabi.newpipe.ui.theme.AppTheme
+import java.net.UnknownHostException
+
+@RunWith(AndroidJUnit4::class)
+class ErrorPanelTest {
+    @get:Rule
+    val composeRule = createAndroidComposeRule<ComponentActivity>()
+
+    private fun setErrorPanel(errorInfo: ErrorInfo, onRetry: (() -> Unit)? = null) {
+        composeRule.setContent {
+            AppTheme {
+                ErrorPanel(errorInfo = errorInfo, onRetry = onRetry)
+            }
+        }
+    }
+    private fun text(@StringRes id: Int) = composeRule.activity.getString(id)
+
+    /**
+     * Test Network Error
+     */
+    @Test
+    fun testNetworkErrorShowsRetryWithoutReportButton() {
+        val networkErrorInfo = ErrorInfo(
+            throwable = UnknownHostException("offline"),
+            userAction = UserAction.REQUESTED_STREAM,
+            request = "https://example.com/watch?v=foo"
+        )
+
+        setErrorPanel(networkErrorInfo, onRetry = {})
+        composeRule.onNodeWithText(text(R.string.network_error)).assertIsDisplayed()
+        composeRule.onNodeWithText(text(R.string.retry), ignoreCase = true).assertIsDisplayed()
+        composeRule.onNodeWithText(text(R.string.error_snackbar_action), ignoreCase = true)
+            .assertDoesNotExist()
+        composeRule.onNodeWithText(text(R.string.recaptcha_solve), ignoreCase = true)
+            .assertDoesNotExist()
+    }
+
+    /**
+     * Test Unexpected Error, Shows Report and Retry buttons
+     */
+    @Test
+    fun unexpectedErrorShowsReportAndRetryButtons() {
+        val unexpectedErrorInfo = ErrorInfo(
+            throwable = RuntimeException("Unexpected error"),
+            userAction = UserAction.REQUESTED_STREAM,
+            request = "https://example.com/watch?v=bar"
+        )
+
+        setErrorPanel(unexpectedErrorInfo, onRetry = {})
+        composeRule.onNodeWithText(text(R.string.error_snackbar_message)).assertIsDisplayed()
+        composeRule.onNodeWithText(text(R.string.retry), ignoreCase = true).assertIsDisplayed()
+        composeRule.onNodeWithText(text(R.string.error_snackbar_action), ignoreCase = true)
+            .assertIsDisplayed()
+    }
+
+    /**
+     * Test Recaptcha Error shows solve, retry and open in browser buttons
+     */
+    @Test
+    fun recaptchaErrorShowsSolveAndRetryOpenInBrowserButtons() {
+        var retryClicked = false
+        val recaptchaErrorInfo = ErrorInfo(
+            throwable = ReCaptchaException(
+                "Recaptcha required",
+                "https://example.com/captcha"
+            ),
+            userAction = UserAction.REQUESTED_STREAM,
+            request = "https://example.com/watch?v=baz",
+            openInBrowserUrl = "https://example.com/watch?v=baz"
+        )
+
+        setErrorPanel(
+            errorInfo = recaptchaErrorInfo,
+            onRetry = { retryClicked = true }
+
+        )
+        composeRule.onNodeWithText(text(R.string.recaptcha_solve), ignoreCase = true)
+            .assertIsDisplayed()
+        composeRule.onNodeWithText(text(R.string.retry), ignoreCase = true)
+            .assertIsDisplayed()
+            .performClick()
+        composeRule.onNodeWithText(text(R.string.open_in_browser), ignoreCase = true)
+            .assertIsDisplayed()
+        composeRule.onNodeWithText(text(R.string.error_snackbar_action), ignoreCase = true)
+            .assertDoesNotExist()
+        assert(retryClicked) { "onRetry callback should have been invoked" }
+    }
+
+    /**
+     * Test Content Not Available Error hides retry button
+     */
+    @Test
+    fun testNonRetryableErrorHidesRetryAndReportButtons() {
+        val contentNotAvailable = ErrorInfo(
+            throwable = ContentNotAvailableException("Video has been removed"),
+            userAction = UserAction.REQUESTED_STREAM,
+            request = "https://example.com/watch?v=qux"
+        )
+
+        setErrorPanel(contentNotAvailable)
+
+        composeRule.onNodeWithText(text(R.string.content_not_available))
+            .assertIsDisplayed()
+        composeRule.onNodeWithText(text(R.string.retry), ignoreCase = true)
+            .assertDoesNotExist()
+        composeRule.onNodeWithText(text(R.string.error_snackbar_action), ignoreCase = true)
+            .assertDoesNotExist()
+    }
+}

app/src/androidTest/java/org/schabi/newpipe/ui/components/video/comment/CommentSectionInstrumentedTest.kt

@@ -0,0 +1,358 @@
+package org.schabi.newpipe.ui.components.video.comment
+
+import androidx.annotation.StringRes
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.heightIn
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.rememberLazyListState
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.input.nestedscroll.nestedScroll
+import androidx.compose.ui.platform.rememberNestedScrollInteropConnection
+import androidx.compose.ui.platform.testTag
+import androidx.compose.ui.res.pluralStringResource
+import androidx.compose.ui.test.ExperimentalTestApi
+import androidx.compose.ui.test.assertIsDisplayed
+import androidx.compose.ui.test.hasClickAction
+import androidx.compose.ui.test.hasText
+import androidx.compose.ui.test.junit4.createAndroidComposeRule
+import androidx.compose.ui.test.onNodeWithTag
+import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.test.performClick
+import androidx.compose.ui.test.performScrollTo
+import androidx.compose.ui.test.performScrollToNode
+import androidx.compose.ui.unit.dp
+import androidx.paging.LoadState
+import androidx.paging.LoadStates
+import androidx.paging.PagingData
+import androidx.paging.compose.collectAsLazyPagingItems
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.schabi.newpipe.R
+import org.schabi.newpipe.error.ErrorInfo
+import org.schabi.newpipe.error.UserAction
+import org.schabi.newpipe.extractor.Page
+import org.schabi.newpipe.extractor.comments.CommentsInfoItem
+import org.schabi.newpipe.extractor.exceptions.ReCaptchaException
+import org.schabi.newpipe.extractor.stream.Description
+import org.schabi.newpipe.ui.components.common.ErrorPanel
+import org.schabi.newpipe.ui.components.common.LazyColumnThemedScrollbar
+import org.schabi.newpipe.ui.components.common.LoadingIndicator
+import org.schabi.newpipe.ui.emptystate.EmptyStateComposable
+import org.schabi.newpipe.ui.emptystate.EmptyStateSpec
+import org.schabi.newpipe.ui.theme.AppTheme
+import org.schabi.newpipe.viewmodels.util.Resource
+import java.net.UnknownHostException
+
+class CommentSectionInstrumentedTest {
+
+    @get:Rule
+    val composeRule = createAndroidComposeRule<androidx.activity.ComponentActivity>()
+
+    private val uiStateFlow = MutableStateFlow<Resource<CommentInfo>>(Resource.Loading)
+    private val pagingFlow = MutableStateFlow(PagingData.empty<CommentsInfoItem>())
+    private fun string(@StringRes resId: Int) = composeRule.activity.getString(resId)
+
+    @Before
+    fun setUp() {
+        composeRule.setContent {
+            AppTheme {
+                TestCommentSection(uiStateFlow = uiStateFlow, commentsFlow = pagingFlow)
+            }
+        }
+    }
+
+    private fun successState(commentCount: Int) = Resource.Success(
+        CommentInfo(
+            serviceId = 0,
+            url = "",
+            comments = emptyList(),
+            nextPage = null,
+            commentCount = commentCount,
+            isCommentsDisabled = false
+        )
+    )
+
+    @Test
+    fun commentListLoadsAndScrolls() {
+        val comments = (1..25).map { index ->
+            CommentsInfoItem(
+                commentText = Description("Comment $index", Description.PLAIN_TEXT),
+                uploaderName = "Uploader $index",
+                replies = Page(""),
+                replyCount = 0
+            )
+        }
+        uiStateFlow.value = successState(comments.size)
+        pagingFlow.value = PagingData.from(comments)
+        composeRule.waitForIdle()
+        composeRule.onNodeWithText("Comment 1").assertIsDisplayed()
+        composeRule.onNodeWithTag("comment_list")
+            .performScrollToNode(hasText("Comment 25"))
+        composeRule.onNodeWithText("Comment 25").assertIsDisplayed()
+    }
+
+    @OptIn(ExperimentalTestApi::class)
+    @Test
+    fun pagingErrorShowsErrorPanelAndAllowsRetry() {
+        uiStateFlow.value = successState(10)
+        pagingFlow.value = PagingData.from(
+            data = emptyList(),
+            sourceLoadStates = LoadStates(
+                refresh = LoadState.Error(ReCaptchaException("captcha required", "https://example.com")),
+                prepend = LoadState.NotLoading(true),
+                append = LoadState.NotLoading(true)
+            )
+        )
+        composeRule.waitForIdle()
+
+        val solveMatcher = hasText(string(R.string.recaptcha_solve), ignoreCase = true)
+            .and(hasClickAction())
+        val retryMatcher = hasText(string(R.string.retry), ignoreCase = true)
+            .and(hasClickAction())
+
+        composeRule.waitUntil(timeoutMillis = 5_000) {
+            composeRule.onAllNodes(solveMatcher).fetchSemanticsNodes().isNotEmpty()
+        }
+        composeRule.waitUntil(timeoutMillis = 5_000) {
+            composeRule.onAllNodes(retryMatcher).fetchSemanticsNodes().isNotEmpty()
+        }
+
+        composeRule.onNode(retryMatcher)
+            .performScrollTo()
+            .performClick()
+
+        val recoveredComment = CommentsInfoItem(
+            commentText = Description("Recovered comment", Description.PLAIN_TEXT),
+            uploaderName = "Uploader",
+            replies = Page(""),
+            replyCount = 0
+        )
+
+        uiStateFlow.value = successState(1)
+        pagingFlow.value = PagingData.from(
+            data = listOf(recoveredComment),
+            sourceLoadStates = LoadStates(
+                refresh = LoadState.NotLoading(false),
+                prepend = LoadState.NotLoading(true),
+                append = LoadState.NotLoading(true)
+            )
+        )
+        composeRule.waitForIdle()
+
+        composeRule.waitUntil(timeoutMillis = 5_000) {
+            composeRule.onAllNodes(hasText("Recovered comment"))
+                .fetchSemanticsNodes()
+                .isNotEmpty()
+        }
+        composeRule.onNodeWithText("Recovered comment").assertIsDisplayed()
+
+        composeRule.onNode(solveMatcher).assertDoesNotExist()
+        composeRule.onNode(retryMatcher).assertDoesNotExist()
+    }
+
+    @OptIn(ExperimentalTestApi::class)
+    @Test
+    fun resourceErrorShowsErrorPanelAndRetry() {
+        uiStateFlow.value = Resource.Error(UnknownHostException("offline"))
+        composeRule.waitForIdle()
+
+        composeRule.onNodeWithText(string(R.string.network_error)).assertIsDisplayed()
+        val retryMatcher = hasText(string(R.string.retry), ignoreCase = true)
+            .and(hasClickAction())
+        composeRule.waitUntil(timeoutMillis = 5_000) {
+            composeRule.onAllNodes(retryMatcher).fetchSemanticsNodes().isNotEmpty()
+        }
+
+        composeRule.onNode(retryMatcher)
+            .performScrollTo()
+            .performClick()
+
+        val recoveredComment = CommentsInfoItem(
+            commentText = Description("Recovered comment", Description.PLAIN_TEXT),
+            uploaderName = "Uploader",
+            replies = Page(""),
+            replyCount = 0
+        )
+
+        uiStateFlow.value = successState(1)
+        pagingFlow.value = PagingData.from(
+            data = listOf(recoveredComment),
+            sourceLoadStates = LoadStates(
+                refresh = LoadState.NotLoading(false),
+                prepend = LoadState.NotLoading(true),
+                append = LoadState.NotLoading(true)
+            )
+        )
+        composeRule.waitForIdle()
+
+        composeRule.waitUntil(timeoutMillis = 5_000) {
+            composeRule.onAllNodes(hasText("Recovered comment"))
+                .fetchSemanticsNodes()
+                .isNotEmpty()
+        }
+        composeRule.onNodeWithText("Recovered comment").assertIsDisplayed()
+
+        composeRule.onNodeWithText(string(R.string.network_error))
+            .assertDoesNotExist()
+        composeRule.onNode(retryMatcher).assertDoesNotExist()
+    }
+
+    @OptIn(ExperimentalTestApi::class)
+    @Test
+    fun retryAfterErrorRecoversList() {
+        uiStateFlow.value = Resource.Error(RuntimeException("boom"))
+        composeRule.waitForIdle()
+
+        val retryMatcher = hasText(string(R.string.retry), ignoreCase = true)
+            .and(hasClickAction())
+        composeRule.waitUntil(timeoutMillis = 5_000) {
+            composeRule.onAllNodes(retryMatcher).fetchSemanticsNodes().isNotEmpty()
+        }
+        composeRule.onNode(retryMatcher)
+            .performScrollTo()
+            .performClick()
+
+        val firstComment = CommentsInfoItem(
+            commentText = Description("First comment", Description.PLAIN_TEXT),
+            uploaderName = "Uploader",
+            replies = Page(""),
+            replyCount = 0
+        )
+
+        uiStateFlow.value = successState(1)
+        pagingFlow.value = PagingData.from(
+            data = listOf(firstComment),
+            sourceLoadStates = LoadStates(
+                refresh = LoadState.NotLoading(false),
+                prepend = LoadState.NotLoading(true),
+                append = LoadState.NotLoading(true)
+            )
+        )
+        composeRule.waitForIdle()
+        composeRule.waitUntil(timeoutMillis = 5_000) {
+            composeRule.onAllNodes(hasText("First comment"))
+                .fetchSemanticsNodes()
+                .isNotEmpty()
+        }
+        composeRule.onNodeWithText("First comment").assertIsDisplayed()
+
+        composeRule.onNodeWithText(string(R.string.network_error))
+            .assertDoesNotExist()
+        composeRule.onNode(retryMatcher).assertDoesNotExist()
+    }
+}
+
+@Composable
+private fun TestCommentSection(
+    uiStateFlow: StateFlow<Resource<CommentInfo>>,
+    commentsFlow: Flow<PagingData<CommentsInfoItem>>
+) {
+    val uiState by uiStateFlow.collectAsState()
+    val comments = commentsFlow.collectAsLazyPagingItems()
+    val nestedScrollInterop = rememberNestedScrollInteropConnection()
+    val listState = rememberLazyListState()
+    val COMMENT_LIST_TAG = "comment_list"
+
+    LazyColumnThemedScrollbar(state = listState) {
+        LazyColumn(
+            modifier = Modifier
+                .testTag(COMMENT_LIST_TAG)
+                .nestedScroll(nestedScrollInterop),
+            state = listState
+        ) {
+            when (uiState) {
+                is Resource.Loading -> item {
+                    LoadingIndicator(modifier = Modifier.padding(top = 8.dp))
+                }
+                is Resource.Success -> {
+                    val commentInfo = (uiState as Resource.Success<CommentInfo>).data
+                    val count = commentInfo.commentCount
+
+                    when {
+                        commentInfo.isCommentsDisabled -> item {
+                            EmptyStateComposable(
+                                spec = EmptyStateSpec.DisabledComments,
+                                modifier = Modifier
+                                    .fillMaxWidth()
+                                    .heightIn(min = 128.dp)
+                            )
+                        }
+                        count == 0 -> item {
+                            EmptyStateComposable(
+                                spec = EmptyStateSpec.NoComments,
+                                modifier = Modifier
+                                    .fillMaxWidth()
+                                    .heightIn(min = 128.dp)
+                            )
+                        }
+                        else -> {
+                            if (count >= 0) {
+                                item {
+                                    Text(
+                                        modifier = Modifier
+                                            .padding(start = 12.dp, end = 12.dp, bottom = 4.dp),
+                                        text = pluralStringResource(R.plurals.comments, count, count),
+                                        maxLines = 1,
+                                        style = MaterialTheme.typography.titleMedium
+                                    )
+                                }
+                            }
+                            when (val refresh = comments.loadState.refresh) {
+                                is LoadState.Loading -> item {
+                                    LoadingIndicator(modifier = Modifier.padding(top = 8.dp))
+                                }
+                                is LoadState.Error -> item {
+                                    Box(
+                                        modifier = Modifier.fillMaxWidth()
+                                    ) {
+                                        ErrorPanel(
+                                            errorInfo = ErrorInfo(
+                                                throwable = refresh.error,
+                                                userAction = UserAction.REQUESTED_COMMENTS,
+                                                request = "comments"
+                                            ),
+                                            onRetry = { comments.retry() },
+                                            modifier = Modifier.align(Alignment.Center)
+                                        )
+                                    }
+                                }
+                                else -> items(comments.itemCount) { index ->
+                                    Comment(comment = comments[index]!!) {}
+                                }
+                            }
+                        }
+                    }
+                }
+                is Resource.Error -> item {
+                    Box(
+                        modifier = Modifier.fillMaxSize(),
+                        contentAlignment = Alignment.Center
+                    ) {
+                        ErrorPanel(
+                            errorInfo = ErrorInfo(
+                                throwable = (uiState as Resource.Error).throwable,
+                                userAction = UserAction.REQUESTED_COMMENTS,
+                                request = "comments"
+                            ),
+                            onRetry = { comments.retry() },
+                            modifier = Modifier.align(Alignment.Center)
+                        )
+                    }
+                }
+            }
+        }
+    }
+}

app/src/main/java/org/schabi/newpipe/ui/components/common/ErrorPanel.kt

@@ -1,6 +1,7 @@
 package org.schabi.newpipe.ui.components.common
 
 import android.content.Intent
+import android.content.res.Configuration
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
 import androidx.compose.material3.MaterialTheme
@@ -86,7 +87,8 @@ fun ErrorPanel(
     }
 }
 
-@Preview(showBackground = true, widthDp = 360, heightDp = 640, backgroundColor = 0xffffffff)
+@Preview(name = "Light mode", uiMode = Configuration.UI_MODE_NIGHT_NO)
+@Preview(name = "Dark mode", uiMode = Configuration.UI_MODE_NIGHT_YES)
 @Composable
 fun ErrorPanelPreview() {
     AppTheme {

gradle/libs.versions.toml

@@ -88,6 +88,8 @@ androidx-compose-adaptive = { group = "androidx.compose.material3.adaptive", nam
 androidx-compose-bom = { group = "androidx.compose", name = "compose-bom", version.ref = "jetpack-compose" }
 androidx-compose-material-icons-extended = { group = "androidx.compose.material", name = "material-icons-extended" }
 androidx-compose-material3 = { group = "androidx.compose.material3", name = "material3" }
+androidx-compose-ui-test-junit4 = { group = "androidx.compose.ui", name = "ui-test-junit4" }
+androidx-compose-ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-manifest" }
 androidx-compose-ui-text = { group = "androidx.compose.ui", name = "ui-text" }
 androidx-compose-ui-tooling = { group = "androidx.compose.ui", name = "ui-tooling" }
 androidx-compose-ui-tooling-preview = { group = "androidx.compose.ui", name = "ui-tooling-preview" }