* fix all violation of Roslyn analyzer rules and ReSharper inspections

* rename variable `nonTracked` to `notTracked` in linq query syntax @ `SaverChangeSet.AllAfter`
* fix outdated comments @ SaverWithRevision.cs
@ crawler

* rename params of `(Except|Intersect)ByKey()` from `first` & `second` to `pairs` & `keys` @ shared/ExtensionMethods.cs
@ c#

c#/crawler/src/Tieba/Crawl/Saver/Post/PostSaver.cs

@@ -1,5 +1,3 @@
-using LinqKit;
-
 namespace tbm.Crawler.Tieba.Crawl.Saver.Post;
 
 public abstract class PostSaver<TPost, TBaseRevision, TPostId>(

c#/crawler/src/Tieba/Crawl/Saver/Post/ThreadSaver.cs

@@ -1,5 +1,3 @@
-using LinqKit;
-
 namespace tbm.Crawler.Tieba.Crawl.Saver.Post;
 
 public partial class ThreadSaver(

c#/crawler/src/Tieba/Crawl/Saver/Related/AuthorRevisionSaver.cs

@@ -91,6 +91,7 @@ private void Save<TPost, TRevision, TValue>(
 
     // locking key only using AuthorRevision.Fid and Uid, ignoring TriggeredBy
     // this prevents inserting multiple entities with similar time and other fields with the same values
+    // ReSharper disable once NotAccessedPositionalProperty.Global
     public record UniqueAuthorRevision(Fid Fid, Uid Uid);
 
     private sealed class LatestAuthorRevisionProjection<TValue>

c#/crawler/src/Tieba/Crawl/Saver/SaverChangeSet.cs

@@ -21,9 +21,9 @@ public class SaverChangeSet<TPost>(
 
     // https://stackoverflow.com/questions/3404975/left-outer-join-in-linq/23558389#23558389
     public IReadOnlyCollection<TPost> AllAfter { get; } = (
-        from nonTracked in existingAfterAndNewlyAdded
+        from notTracked in existingAfterAndNewlyAdded
         join inTracking in existingAfterInTracking
-            on postIdSelector(nonTracked) equals postIdSelector(inTracking) into inTrackings
+            on postIdSelector(notTracked) equals postIdSelector(inTracking) into inTrackings
         from inTracking in inTrackings.DefaultIfEmpty()
-        select inTracking ?? nonTracked).ToList().AsReadOnly();
+        select inTracking ?? notTracked).ToList().AsReadOnly();
 }

c#/crawler/src/Tieba/Crawl/Saver/SaverWithRevision.cs

@@ -62,14 +62,8 @@ public partial class SaverWithRevision<TBaseRevision, TRevisionId>
 }
 public partial class SaverWithRevision<TBaseRevision, TRevisionId>
 {
-    private static bool IsTimestampingFieldName(string name) => name is nameof(BasePost.LastSeenAt)
-        or nameof(TimestampedEntity.CreatedAt) or nameof(TimestampedEntity.UpdatedAt);
-
     protected abstract NullFieldsBitMask GetRevisionNullFieldBitMask(string fieldName);
 
-    protected record ExistingAndNewEntity<TEntity>(TEntity Existing, TEntity New) where TEntity : RowVersionedEntity;
-    protected record MaybeExistingAndNewEntity<TEntity>(TEntity? Existing, TEntity New) where TEntity : RowVersionedEntity;
-
     protected IEnumerable<ExistingAndNewEntity<TEntity>> SaveNewEntities<TEntity>(
         CrawlerDbContext db,
         IReadOnlyCollection<MaybeExistingAndNewEntity<TEntity>> maybeEntities)
@@ -103,7 +97,7 @@ on newNavigation.Metadata.Name equals existingNavigation.Metadata.Name
 
             // rollback changes that overwrite original values with the default value 0 or null
             // for all fields of TimestampedEntity and BasePost.LastSeenAt
-            // this will also affect the entity instance which entityInTracking references to it
+            // this will also affect the entity instance which existingEntity references to it
             entityEntry.Properties
                 .Where(prop => prop.IsModified && IsTimestampingFieldName(prop.Metadata.Name))
                 .ForEach(prop => prop.IsModified = false);
@@ -141,7 +135,7 @@ protected void SaveExistingEntityRevisions<TEntity, TRevision>(
                         pName, p.OriginalValue, p.CurrentValue)))
                 {
                     p.IsModified = false;
-                    continue; // skip following revision check
+                    continue; // skip any further revision check
                 }
                 if (FieldRevisionIgnorance(
                         pName, p.OriginalValue, p.CurrentValue)
@@ -151,7 +145,7 @@ protected void SaveExistingEntityRevisions<TEntity, TRevision>(
 
                 if (!IRevisionProperties.Cache[typeof(TRevision)].TryGetValue(pName, out var revisionProp))
                 {
-                    object? ToHexWhenByteArray(object? value) =>
+                    static object? ToHexWhenByteArray(object? value) =>
                         value is byte[] bytes ? bytes.ToHex() : value;
                     logger.LogWarning("Updating field {} is not existing in revision table, " +
                                        "newValue={}, oldValue={}, newObject={}, oldObject={}",
@@ -163,7 +157,7 @@ protected void SaveExistingEntityRevisions<TEntity, TRevision>(
                 {
                     revision ??= revisionFactory(existingEntity);
 
-                    // quote from MSDN https://learn.microsoft.com/en-us/dotnet/api/system.reflection.propertyinfo.setvalue
+                    // https://learn.microsoft.com/en-us/dotnet/api/system.reflection.propertyinfo.setvalue
                     // If the property type of this PropertyInfo object is a value type and value is null
                     // the property will be set to the default value for that type.
                     // https://stackoverflow.com/questions/3049477/propertyinfo-setvalue-and-nulls
@@ -195,4 +189,10 @@ protected void SaveExistingEntityRevisions<TEntity, TRevision>(
             .GroupBy(pair => pair.Key, pair => pair.Value)
             .ForEach(g => AddSplitRevisionsDelegatesKeyByEntityType.Value[g.Key](db, g));
     }
+
+    private static bool IsTimestampingFieldName(string name) => name is nameof(BasePost.LastSeenAt)
+        or nameof(TimestampedEntity.CreatedAt) or nameof(TimestampedEntity.UpdatedAt);
+
+    protected record ExistingAndNewEntity<TEntity>(TEntity Existing, TEntity New) where TEntity : RowVersionedEntity;
+    protected record MaybeExistingAndNewEntity<TEntity>(TEntity? Existing, TEntity New) where TEntity : RowVersionedEntity;
 }

c#/shared/src/ExtensionMethods.cs

@@ -39,13 +39,13 @@ public static IEnumerable<TValue> Values<TKey, TValue>(this IEnumerable<KeyValue
         pairs.Select(i => i.Value);
 
     public static IEnumerable<KeyValuePair<TKey, TValue>> ExceptByKey<TKey, TValue>(
-        this IEnumerable<KeyValuePair<TKey, TValue>> first,
-        IEnumerable<TKey> second) =>
-        first.ExceptBy(second, pair => pair.Key);
+        this IEnumerable<KeyValuePair<TKey, TValue>> pairs,
+        IEnumerable<TKey> keys) =>
+        pairs.ExceptBy(keys, pair => pair.Key);
     public static IEnumerable<KeyValuePair<TKey, TValue>> IntersectByKey<TKey, TValue>(
-        this IEnumerable<KeyValuePair<TKey, TValue>> first,
-        IEnumerable<TKey> second) =>
-        first.IntersectBy(second, pair => pair.Key);
+        this IEnumerable<KeyValuePair<TKey, TValue>> pairs,
+        IEnumerable<TKey> keys) =>
+        pairs.IntersectBy(keys, pair => pair.Key);
 
     public static IEnumerable<T> Flatten2<T>(this IEnumerable<IEnumerable<T>> source) =>
         source.SelectMany(i => i);