fixed a bug with CopyTo and added optimizations to TList<T> constructors

Author: sglienke

Source/Base/Collections/Spring.Collections.Base.pas

@@ -219,8 +219,8 @@   TCollectionBase<T> = class abstract(TEnumerableBase<T>, ICollection<T>, IReadO
     procedure Changed(const item: T; action: TCollectionChangedAction); virtual;
   public
     constructor Create; override;
-    constructor Create(const collection: array of T); overload;
-    constructor Create(const collection: IEnumerable<T>); overload;
+    constructor Create(const collection: array of T); overload; virtual;
+    constructor Create(const collection: IEnumerable<T>); overload; virtual;
 
     procedure Add(const item: T);
     procedure AddRange(const collection: array of T); overload; virtual;

Source/Base/Collections/Spring.Collections.Lists.pas

@@ -98,6 +98,8 @@       TEnumerator = class(TEnumeratorBase<T>)
     function EnsureCapacity(value: Integer): Integer;
   public
     constructor Create; override;
+    constructor Create(const collection: array of T); override;
+    constructor Create(const collection: IEnumerable<T>); override;
     destructor Destroy; override;
 
     function GetEnumerator: IEnumerator<T>; override;
@@ -268,6 +270,38 @@ constructor TList<T>.Create;
     fArrayManager := TMoveArrayManager<T>.Create;
 end;
 
+constructor TList<T>.Create(const collection: array of T);
+var
+  i: Integer;
+begin
+  Create;
+  fCount := Length(collection);
+  if fCount > 0 then
+  begin
+    SetLength(fItems, fCount);
+    for i := Low(collection) to High(collection) do
+      fItems[i] := collection[i];
+  end;
+end;
+
+constructor TList<T>.Create(const collection: IEnumerable<T>);
+var
+  c: ICollection<T>;
+begin
+  if Supports(collection, ICollection<T>, c) then
+  begin
+    Create;
+    fCount := c.Count;
+    if fCount > 0 then
+    begin
+      SetLength(fItems, fCount);
+      c.CopyTo(fItems, 0);
+    end;
+  end
+  else
+    inherited;
+end;
+
 destructor TList<T>.Destroy;
 begin
   inherited Destroy;
@@ -568,12 +602,18 @@ function TList<T>.Contains(const value: T;
 end;
 
 procedure TList<T>.CopyTo(var values: TArray<T>; index: Integer);
+var
+  i: Integer;
 begin
 {$IFDEF SPRING_ENABLE_GUARD}
   Guard.CheckRange(Length(values), index, fCount);
 {$ENDIF}
 
-  fArrayManager.Move(fItems, TArrayOfT(values), 0, index, fCount);
+  for i := 0 to fCount - 1 do
+  begin
+    values[index] := fItems[i];
+    Inc(index);
+  end;
 end;
 
 function TList<T>.ToArray: TArray<T>;

Tests/Source/Base/Spring.Tests.Collections.pas

@@ -322,6 +322,7 @@   TTestInterfaceList = class(TTestCase)
   published
     procedure TestInterfaceListCreate;
     procedure TestGetElementType;
+    procedure TestCopyTo;
   end;
 
   TMyCollectionItem = class(TCollectionItem);
@@ -1885,6 +1886,23 @@ procedure TTestInterfaceList.SetUp;
   SUT := TInterfaceList<IInvokable>.Create as IList<IInvokable>;
 end;
 
+type
+  TInvokable = class(TInterfacedObject, IInvokable);
+
+procedure TTestInterfaceList.TestCopyTo;
+var
+  values: TArray<IInvokable>;
+  i: Integer;
+begin
+  for i := 0 to MaxItems - 1 do
+    SUT.Add(IInvokable(TInvokable.Create));
+  SetLength(values, MaxItems);
+  SUT.CopyTo(values, 0);
+  CheckEquals(MaxItems, Length(values));
+  CheckSame(SUT.First, values[0]);
+  CheckSame(SUT.Last, values[MaxItems-1]);
+end;
+
 procedure TTestInterfaceList.TestGetElementType;
 begin
   Check(TypeInfo(IInvokable) = SUT.ElementType);