Refactor other Clone()

SergeiPavlov · SergeiPavlov · commit efcd3424f37c · 2022-07-08T00:36:59.000-07:00
diff --git a/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlCase.cs b/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlCase.cs
@@ -105,23 +105,18 @@ public override void ReplaceWith(SqlExpression expression)
         cases.Add(pair);
     }
 
-    internal override SqlCase Clone(SqlNodeCloneContext context)
-    {
-      if (context.NodeMapping.TryGetValue(this, out var v)) {
-        return (SqlCase)v;
-      }
+    internal override SqlCase Clone(SqlNodeCloneContext context) =>
+      context.GetOrAdd(this, static (t, c) => {
+        var clone = new SqlCase(t.value?.Clone(c));
 
-      var clone = new SqlCase(value.IsNullReference() ? null : value.Clone(context));
+        if (t.@else is not null)
+          clone.Else = t.@else.Clone(c);
 
-      if (!@else.IsNullReference())
-        clone.Else = @else.Clone(context);
+        foreach (KeyValuePair<SqlExpression, SqlExpression> pair in t.cases)
+          clone[pair.Key.Clone(c)] = pair.Value.Clone(c);
 
-      foreach (KeyValuePair<SqlExpression, SqlExpression> pair in cases)
-        clone[pair.Key.Clone(context)] = pair.Value.Clone(context);
-
-      context.NodeMapping[this] = clone;
-      return clone;
-    }
+        return clone;
+      });
 
     public override void AcceptVisitor(ISqlVisitor visitor)
     {
diff --git a/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlComment.cs b/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlComment.cs
@@ -25,15 +25,9 @@ public override void ReplaceWith(SqlExpression expression)
       Text = replacingExpression.Text;
     }
 
-    internal override SqlComment Clone(SqlNodeCloneContext context)
-    {
-      if (context.NodeMapping.TryGetValue(this, out var node))
-        return (SqlComment)node;
-
-      var clone = new SqlComment(Text);
-      context.NodeMapping[this] = clone;
-      return clone;
-    }
+    internal override SqlComment Clone(SqlNodeCloneContext context) =>
+      context.GetOrAdd(this, static (t, c) =>
+        new SqlComment(t.Text));
 
     public override void AcceptVisitor(ISqlVisitor visitor)
     {
diff --git a/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlCustomFunctionCall.cs b/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlCustomFunctionCall.cs
@@ -35,18 +35,13 @@ public override void ReplaceWith(SqlExpression expression)
         Arguments.Add(argument);
     }
 
-    internal override SqlCustomFunctionCall Clone(SqlNodeCloneContext context)
-    {
-      if (context.NodeMapping.TryGetValue(this, out var value)) {
-        return (SqlCustomFunctionCall)value;
-      }
-
-      var clone = new SqlCustomFunctionCall(FunctionType);
-      for (int i = 0, l = Arguments.Count; i < l; i++)
-        clone.Arguments.Add(Arguments[i].Clone(context));
-      context.NodeMapping[this] = clone;
-      return clone;
-    }
+    internal override SqlCustomFunctionCall Clone(SqlNodeCloneContext context) =>
+      context.GetOrAdd(this, static (t, c) => {
+        var clone = new SqlCustomFunctionCall(t.FunctionType);
+        for (int i = 0, l = t.Arguments.Count; i < l; i++)
+          clone.Arguments.Add(t.Arguments[i].Clone(c));
+        return clone;
+      });
 
     public override void AcceptVisitor(ISqlVisitor visitor)
     {
diff --git a/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlDynamicFilter.cs b/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlDynamicFilter.cs
@@ -15,19 +15,15 @@ public class SqlDynamicFilter : SqlExpression
 
     public List<SqlExpression> Expressions { get; private set; }
 
-    internal override SqlDynamicFilter Clone(SqlNodeCloneContext context)
-    {
-      if (context.NodeMapping.TryGetValue(this, out var value)) {
-        return (SqlDynamicFilter)value;
-      }
-      var clone = new SqlDynamicFilter(Id);
-      foreach (var expression in Expressions) {
-        clone.Expressions.Add(expression.Clone(context));
-      }
-
-      context.NodeMapping[this] = clone;
-      return clone;
-    }
+    internal override SqlDynamicFilter Clone(SqlNodeCloneContext context) =>
+      context.GetOrAdd(this, static (t, c) => {
+        var clone = new SqlDynamicFilter(t.Id);
+        foreach (var expression in t.Expressions) {
+          clone.Expressions.Add(expression.Clone(c));
+        }
+
+        return clone;
+      });
 
     public override void AcceptVisitor(ISqlVisitor visitor)
     {
diff --git a/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlFunctionCall.cs b/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlFunctionCall.cs
@@ -33,18 +33,13 @@ public override void ReplaceWith(SqlExpression expression)
         Arguments.Add(argument);
     }
 
-    internal override SqlFunctionCall Clone(SqlNodeCloneContext context)
-    {
-      if (context.NodeMapping.TryGetValue(this, out var value)) {
-        return (SqlFunctionCall)value;
-      }
-
-      var clone = new SqlFunctionCall(FunctionType);
-      for (int i = 0, l = Arguments.Count; i < l; i++)
-        clone.Arguments.Add(Arguments[i].Clone(context));
-      context.NodeMapping[this] = clone;
-      return clone;
-    }
+    internal override SqlFunctionCall Clone(SqlNodeCloneContext context) =>
+      context.GetOrAdd(this, static (t, c) => {
+        var clone = new SqlFunctionCall(t.FunctionType);
+        for (int i = 0, l = t.Arguments.Count; i < l; i++)
+          clone.Arguments.Add(t.Arguments[i].Clone(c));
+        return clone;
+      });
 
     public override void AcceptVisitor(ISqlVisitor visitor)
     {
diff --git a/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlRowNumber.cs b/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlRowNumber.cs
@@ -12,17 +12,13 @@ public class SqlRowNumber : SqlExpression
   {
     public SqlOrderCollection OrderBy { get; private set; }
 
-    internal override SqlRowNumber Clone(SqlNodeCloneContext context)
-    {
-      if (context.NodeMapping.TryGetValue(this, out var value)) {
-        return (SqlRowNumber)value;
-      }
-      var clone = new SqlRowNumber();
-      foreach (SqlOrder so in OrderBy)
-        clone.OrderBy.Add((SqlOrder) so.Clone(context));
-      context.NodeMapping[this] = clone;
-      return clone;
-    }
+    internal override SqlRowNumber Clone(SqlNodeCloneContext context) =>
+      context.GetOrAdd(this, static (t, c) => {
+        var clone = new SqlRowNumber();
+        foreach (SqlOrder so in t.OrderBy)
+          clone.OrderBy.Add(so.Clone(c));
+        return clone;
+      });
 
     public override void AcceptVisitor(ISqlVisitor visitor)
     {
diff --git a/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlSubQuery.cs b/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlSubQuery.cs
@@ -33,22 +33,17 @@ public override void ReplaceWith(SqlExpression expression)
       query = replacingExpression.Query;
     }
 
-    internal override SqlSubQuery Clone(SqlNodeCloneContext context)
-    {
-      if (context.NodeMapping.TryGetValue(this, out var value)) {
-        return (SqlSubQuery)value;
-      }
-
-      SqlSubQuery clone;
-      SqlSelect select = query as SqlSelect;
-      SqlQueryExpression expression = query as SqlQueryExpression;
-      if (select != null)
-        clone = new SqlSubQuery((SqlSelect)select.Clone(context));
-      else 
-        clone = new SqlSubQuery((SqlQueryExpression)expression.Clone(context));
-      context.NodeMapping[this] = clone;
-      return clone;
-    }
+    internal override SqlSubQuery Clone(SqlNodeCloneContext context) =>
+      context.GetOrAdd(this, static (t, c) => {
+        SqlSubQuery clone;
+        SqlSelect select = t.query as SqlSelect;
+        SqlQueryExpression expression = t.query as SqlQueryExpression;
+        if (select != null)
+          clone = new SqlSubQuery(select.Clone(c));
+        else 
+          clone = new SqlSubQuery(expression.Clone(c));
+        return clone;
+      });
 
     public override void AcceptVisitor(ISqlVisitor visitor)
     {
diff --git a/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlTableColumn.cs b/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlTableColumn.cs
@@ -22,22 +22,17 @@ public override void ReplaceWith(SqlExpression expression)
       base.ReplaceWith(expression);
     }
 
-    internal override SqlTableColumn Clone(SqlNodeCloneContext context)
-    {
-      if (context.NodeMapping.TryGetValue(this, out var value)) {
-        return (SqlTableColumn)value;
-      }
-
-      var table = SqlTable;
-      SqlNode clonedTable;
-      if (context.NodeMapping.TryGetValue(SqlTable, out clonedTable)) {
-        table = (SqlTable) clonedTable;
-      }
+    internal override SqlTableColumn Clone(SqlNodeCloneContext context) =>
+      context.GetOrAdd(this, static (t, c) => {
+        var table = t.SqlTable;
+        SqlNode clonedTable;
+        if (c.NodeMapping.TryGetValue(t.SqlTable, out clonedTable)) {
+          table = (SqlTable) clonedTable;
+        }
       
-      var clone = new SqlTableColumn(table, Name);
-      context.NodeMapping[this] = clone;
-      return clone;
-    }
+        var clone = new SqlTableColumn(table, t.Name);
+        return clone;
+      });
 
     // Constructors
 
diff --git a/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlUserFunctionCall.cs b/Orm/Xtensive.Orm/Sql/Dml/Expressions/SqlUserFunctionCall.cs
@@ -34,18 +34,13 @@ public override void ReplaceWith(SqlExpression expression)
         Arguments.Add(argument);
     }
 
-    internal override SqlUserFunctionCall Clone(SqlNodeCloneContext context)
-    {
-      if (context.NodeMapping.TryGetValue(this, out var value)) {
-        return (SqlUserFunctionCall)value;
-      }
-      
-      SqlUserFunctionCall clone = new SqlUserFunctionCall(name);
-      for (int i = 0, l = Arguments.Count; i < l; i++)
-        clone.Arguments.Add(Arguments[i].Clone(context));
-      context.NodeMapping[this] = clone;
-      return clone;
-    }
+    internal override SqlUserFunctionCall Clone(SqlNodeCloneContext context) =>
+      context.GetOrAdd(this, static (t, c) => {
+        SqlUserFunctionCall clone = new SqlUserFunctionCall(t.name);
+        for (int i = 0, l = t.Arguments.Count; i < l; i++)
+          clone.Arguments.Add(t.Arguments[i].Clone(c));
+        return clone;
+      });
 
     internal SqlUserFunctionCall(string name, IEnumerable<SqlExpression> arguments)
       : base(SqlFunctionType.UserDefined, arguments)
diff --git a/Orm/Xtensive.Orm/Sql/Dml/SqlOrder.cs b/Orm/Xtensive.Orm/Sql/Dml/SqlOrder.cs
@@ -31,11 +31,10 @@ public class SqlOrder : SqlNode
     public bool Ascending { get; private set; }
 
     internal override SqlOrder Clone(SqlNodeCloneContext context) =>
-      (SqlOrder) (context.NodeMapping.TryGetValue(this, out var clone)
-        ? clone
-        : context.NodeMapping[this] = (Expression.IsNullReference()
-            ? new SqlOrder(Position, Ascending)
-            : new SqlOrder(Expression.Clone(context), Ascending)));
+      context.GetOrAdd(this, static (t, c) =>
+        t.Expression is null
+            ? new SqlOrder(t.Position, t.Ascending)
+            : new SqlOrder(t.Expression.Clone(c), t.Ascending));
 
     public override void AcceptVisitor(ISqlVisitor visitor)
     {
diff --git a/Orm/Xtensive.Orm/Sql/Dml/SqlQueryRef.cs b/Orm/Xtensive.Orm/Sql/Dml/SqlQueryRef.cs
@@ -23,11 +23,10 @@ public ISqlQueryExpression Query
     }
 
     internal override SqlQueryRef Clone(SqlNodeCloneContext context) =>
-      (SqlQueryRef) (context.NodeMapping.TryGetValue(this, out var clone)
-        ? clone
-        : context.NodeMapping[this] = query is SqlSelect ss
-          ? new SqlQueryRef((SqlSelect) ss.Clone(context), Name)
-          : new SqlQueryRef((SqlQueryExpression) ((SqlQueryExpression) query).Clone(context), Name));
+      context.GetOrAdd(this, static (t, c) =>
+        t.query is SqlSelect ss
+          ? new SqlQueryRef(ss.Clone(c), t.Name)
+          : new SqlQueryRef(((SqlQueryExpression) t.query).Clone(c), t.Name));
 
     public override void AcceptVisitor(ISqlVisitor visitor)
     {
diff --git a/Orm/Xtensive.Orm/Sql/Dml/Statements/SqlSelect.cs b/Orm/Xtensive.Orm/Sql/Dml/Statements/SqlSelect.cs
@@ -193,40 +193,34 @@ public bool HasOffset
       get { return !Offset.IsNullReference(); }
     }
 
-    internal override SqlSelect Clone(SqlNodeCloneContext context)
-    {
-      if (context.NodeMapping.TryGetValue(this, out var value)) {
-        return (SqlSelect)value;
-      }
-
-      SqlSelect clone = new SqlSelect(from==null ? null : from.Clone(context));
-
-      foreach (SqlColumn c in columns)
-        clone.Columns.Add((SqlColumn)c.Clone(context));
-      if (groupBy != null)
-        foreach (SqlColumn c in groupBy)
-          clone.GroupBy.Add((SqlColumn)c.Clone(context));
-      if (!where.IsNullReference())
-        clone.Where = where.Clone(context);
-      if (!having.IsNullReference())
-        clone.Having = having.Clone(context);
-      if (orderBy != null)
-        foreach (SqlOrder so in orderBy)
-          clone.OrderBy.Add(so.Clone(context));
-      clone.Distinct = distinct;
-      clone.Limit = Limit;
-      clone.Offset = Offset;
-      clone.Lock = Lock;
-      clone.Comment = Comment?.Clone(context);
-
-      if (Hints.Count > 0)
-        foreach (SqlHint hint in Hints)
-          clone.Hints.Add((SqlHint)hint.Clone(context));
-
-      context.NodeMapping[this] = clone;
-
-      return clone;
-    }
+    internal override SqlSelect Clone(SqlNodeCloneContext context) =>
+      context.GetOrAdd(this, static (t, c) => {
+        SqlSelect clone = new SqlSelect(t.from==null ? null : t.from.Clone(c));
+
+        foreach (SqlColumn column in t.columns)
+          clone.Columns.Add((SqlColumn)column.Clone(c));
+        if (t.groupBy != null)
+          foreach (SqlColumn column in t.groupBy)
+            clone.GroupBy.Add((SqlColumn)column.Clone(c));
+        if (t.where is not null)
+          clone.Where = t.where.Clone(c);
+        if (t.having is not null)
+          clone.Having = t.having.Clone(c);
+        if (t.orderBy != null)
+          foreach (SqlOrder so in t.orderBy)
+            clone.OrderBy.Add(so.Clone(c));
+        clone.Distinct = t.distinct;
+        clone.Limit = t.Limit;
+        clone.Offset = t.Offset;
+        clone.Lock = t.Lock;
+        clone.Comment = t.Comment?.Clone(c);
+
+        if (t.Hints.Count > 0)
+          foreach (SqlHint hint in t.Hints)
+            clone.Hints.Add((SqlHint)hint.Clone(c));
+
+        return clone;
+      });
 
     /// <summary>
     /// Makes a shallow clone of the instance.
