add debugDescriptionLines for new updater

Summary: The current `IGListAdapterUpdater` implements `-debugDescriptionLines` which is used by `IGListDebugger` to dump information about all the apaters, so lets also implement it for `IGListExperimentalAdapterUpdater`.

Reviewed By: lorixx

Differential Revision: D25884781

fbshipit-source-id: 86b227258f033f0079058af04915171d6a149241

Source/IGListKit/Internal/IGListExperimentalAdapterUpdater+DebugDescription.h

@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import <IGListKit/IGListExperimentalAdapterUpdater.h>
+
+@interface IGListExperimentalAdapterUpdater (DebugDescription)
+
+- (NSArray<NSString *> *)debugDescriptionLines;
+
+@end

Source/IGListKit/Internal/IGListExperimentalAdapterUpdater+DebugDescription.m

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import "IGListExperimentalAdapterUpdater+DebugDescription.h"
+
+#import "IGListBatchUpdateData+DebugDescription.h"
+#import "IGListDebuggingUtilities.h"
+#import "IGListExperimentalAdapterUpdaterInternal.h"
+#import "IGListUpdateTransactable.h"
+
+@implementation IGListExperimentalAdapterUpdater (DebugDescription)
+
+- (NSArray<NSString *> *)debugDescriptionLines {
+    NSMutableArray *debug = [NSMutableArray new];
+#if defined(IGLK_DEBUG_DESCRIPTION_ENABLED) && IGLK_DEBUG_DESCRIPTION_ENABLED
+    [debug addObject:@"Options:"];
+    NSArray<NSString *> *options = @[
+        [NSString stringWithFormat:@"sectionMovesAsDeletesInserts: %@", IGListDebugBOOL(self.sectionMovesAsDeletesInserts)],
+        [NSString stringWithFormat:@"singleItemSectionUpdates: %@", IGListDebugBOOL(self.singleItemSectionUpdates)],
+        [NSString stringWithFormat:@"preferItemReloadsForSectionReloads: %@", IGListDebugBOOL(self.preferItemReloadsForSectionReloads)],
+        [NSString stringWithFormat:@"allowsBackgroundReloading: %@", IGListDebugBOOL(self.allowsBackgroundReloading)],
+        [NSString stringWithFormat:@"allowsReloadingOnTooManyUpdates: %@", IGListDebugBOOL(self.allowsReloadingOnTooManyUpdates)]
+    ];
+    [debug addObjectsFromArray:IGListDebugIndentedLines(options)];
+
+    const IGListBatchUpdateState state = self.transaction ? [self.transaction state] : IGListBatchUpdateStateIdle;
+
+    NSString *stateString;
+    switch (state) {
+        case IGListBatchUpdateStateIdle:
+            stateString = @"Idle";
+            break;
+        case IGListBatchUpdateStateQueuedBatchUpdate:
+            stateString = @"Queued batch update";
+            break;
+        case IGListBatchUpdateStateExecutedBatchUpdateBlock:
+            stateString = @"Executed batch update block";
+            break;
+        case IGListBatchUpdateStateExecutingBatchUpdateBlock:
+            stateString = @"Executing batch update block";
+            break;
+    }
+    [debug addObject:[NSString stringWithFormat:@"State: %@", stateString]];
+
+#endif // #if IGLK_DEBUG_DESCRIPTION_ENABLED
+    return debug;
+}
+
+@end