Add utility method to assert that given channel tabs are in the ones returned by a channel extractor

Only the first content filter of the ListLinkHandler instances provided is
used when collecting all channel tabs of the ListLinkHandler list, as channel
tabs implementations only use one content filter per ListLinkHandler instance.

Co-authored-by: ThetaDev <t.testboy@gmail.com>

Author: 2 people

extractor/src/test/java/org/schabi/newpipe/extractor/ExtractorAsserts.java

@@ -3,8 +3,11 @@
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
@@ -15,6 +18,7 @@
 import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import org.schabi.newpipe.extractor.linkhandler.ListLinkHandler;
 import org.schabi.newpipe.extractor.utils.Utils;
 
 public class ExtractorAsserts {
@@ -144,6 +148,16 @@ public static void assertContains(
         assertNotNull(shouldBeContained, "shouldBeContained is null");
         assertNotNull(container, "container is null");
         assertTrue(container.contains(shouldBeContained),
-                "'" + shouldBeContained + "' should be contained inside '" + container +"'");
+                "'" + shouldBeContained + "' should be contained inside '" + container + "'");
+    }
+
+    public static void assertTabsContained(@Nonnull final List<ListLinkHandler> tabs,
+                                           @Nonnull final String... expectedTabs) {
+        final Set<String> tabSet = tabs.stream()
+                .map(linkHandler -> linkHandler.getContentFilters().get(0))
+                .collect(Collectors.toUnmodifiableSet());
+        Arrays.stream(expectedTabs)
+                .forEach(expectedTab -> assertTrue(tabSet.contains(expectedTab),
+                        "Missing " + expectedTab + " tab (got " + tabSet + ")"));
     }
 }