[typed_data] Deprecate UnmodifiableUint8ListView and friends

This is the first of several steps to remove the unmodifiable views for typed data classes. The end goal is that dart2js has only one class implementing `Uint8List` so that `Uint8List` accesses can always be compiled down to JavaScript code that directly uses indexed property accesses (`a[i]`).

This first step deprecates the unmodifiable view classes to help prevent their use in new code, and adds `asUnmodifiableView()` methods as a replacement for the small number of places that use the classes.

The next steps (see #53785) are to remove uses of the unmodifiable view classes from the SDK. Once this is complete the classes themselves can be removed.

TEST=ci

Issue: #53218
Issue: #53785

Change-Id: I04d4feb0d9f1619e6eee65236e559f5e6adf2661
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/321922
Reviewed-by: Nicholas Shahan <[email protected]>
Reviewed-by: Lasse Nielsen <[email protected]>
Commit-Queue: Stephen Adams <[email protected]>
Reviewed-by: Alexander Markov <[email protected]>
Reviewed-by: Martin Kustermann <[email protected]>
Reviewed-by: Ömer Ağacan <[email protected]>

Author: rakudrama

CHANGELOG.md

@@ -1,5 +1,31 @@
 ## 3.3.0
 
+### Libraries
+
+#### `dart:typed_data`
+
+- **BREAKING CHANGE** (https://github.com/dart-lang/sdk/issues/53218) The
+  unmodifiable view classes for typed data are deprecated. Instead of using the
+  constructors for these classes to create an unmodifiable view, e.g.
+
+  ```dart
+  Uint8List data = ...
+  final readOnlyView = UnmodifableUint8ListView(data);
+  ```
+
+  use the new `asUnmodifiableView()` method:
+
+  ```dart
+  Uint8List data = ...
+  final readOnlyView = data.asUnmodifiableView();
+  ```
+
+  The reason for this change is to allow more flexibility in the implementation
+  of typed data so the native and web platforms can use different strategies
+  for ensuring typed data has good performance.
+
+  The deprecated types will be removed in the next Dart version.
+
 ### Tools
 
 #### Dart command line

sdk/lib/_internal/js_dev_runtime/patch/typed_data_patch.dart

@@ -264,6 +264,8 @@ final class _UnmodifiableByteDataView
 
   _UnmodifiableByteDataView(ByteData data) : _data = data;
 
+  ByteData asUnmodifiableView() => this;
+
   int getInt8(int byteOffset) => _data.getInt8(byteOffset);
 
   void setInt8(int byteOffset, int value) => _unsupported();
@@ -372,6 +374,8 @@ final class _UnmodifiableUint8ListView extends UnmodifiableListBase<int>
   final Uint8List _list;
   _UnmodifiableUint8ListView(Uint8List list) : _list = list;
 
+  Uint8List asUnmodifiableView() => this;
+
   Uint8List _createList(int length) => Uint8List(length);
 }
 
@@ -385,6 +389,8 @@ final class _UnmodifiableInt8ListView extends UnmodifiableListBase<int>
   final Int8List _list;
   _UnmodifiableInt8ListView(Int8List list) : _list = list;
 
+  Int8List asUnmodifiableView() => this;
+
   Int8List _createList(int length) => Int8List(length);
 }
 
@@ -398,6 +404,8 @@ final class _UnmodifiableUint8ClampedListView extends UnmodifiableListBase<int>
   final Uint8ClampedList _list;
   _UnmodifiableUint8ClampedListView(Uint8ClampedList list) : _list = list;
 
+  Uint8ClampedList asUnmodifiableView() => this;
+
   Uint8ClampedList _createList(int length) => Uint8ClampedList(length);
 }
 
@@ -411,6 +419,8 @@ final class _UnmodifiableUint16ListView extends UnmodifiableListBase<int>
   final Uint16List _list;
   _UnmodifiableUint16ListView(Uint16List list) : _list = list;
 
+  Uint16List asUnmodifiableView() => this;
+
   Uint16List _createList(int length) => Uint16List(length);
 }
 
@@ -424,6 +434,8 @@ final class _UnmodifiableInt16ListView extends UnmodifiableListBase<int>
   final Int16List _list;
   _UnmodifiableInt16ListView(Int16List list) : _list = list;
 
+  Int16List asUnmodifiableView() => this;
+
   Int16List _createList(int length) => Int16List(length);
 }
 
@@ -437,6 +449,8 @@ final class _UnmodifiableUint32ListView extends UnmodifiableListBase<int>
   final Uint32List _list;
   _UnmodifiableUint32ListView(Uint32List list) : _list = list;
 
+  Uint32List asUnmodifiableView() => this;
+
   Uint32List _createList(int length) => Uint32List(length);
 }
 
@@ -450,6 +464,8 @@ final class _UnmodifiableInt32ListView extends UnmodifiableListBase<int>
   final Int32List _list;
   _UnmodifiableInt32ListView(Int32List list) : _list = list;
 
+  Int32List asUnmodifiableView() => this;
+
   Int32List _createList(int length) => Int32List(length);
 }
 
@@ -463,6 +479,8 @@ final class _UnmodifiableUint64ListView extends UnmodifiableListBase<int>
   final Uint64List _list;
   _UnmodifiableUint64ListView(Uint64List list) : _list = list;
 
+  Uint64List asUnmodifiableView() => this;
+
   Uint64List _createList(int length) => Uint64List(length);
 }
 
@@ -476,6 +494,8 @@ final class _UnmodifiableInt64ListView extends UnmodifiableListBase<int>
   final Int64List _list;
   _UnmodifiableInt64ListView(Int64List list) : _list = list;
 
+  Int64List asUnmodifiableView() => this;
+
   Int64List _createList(int length) => Int64List(length);
 }
 
@@ -489,6 +509,8 @@ final class _UnmodifiableInt32x4ListView extends UnmodifiableListBase<Int32x4>
   final Int32x4List _list;
   _UnmodifiableInt32x4ListView(Int32x4List list) : _list = list;
 
+  Int32x4List asUnmodifiableView() => this;
+
   Int32x4List _createList(int length) => Int32x4List(length);
 }
 
@@ -503,6 +525,8 @@ final class _UnmodifiableFloat32x4ListView
   final Float32x4List _list;
   _UnmodifiableFloat32x4ListView(Float32x4List list) : _list = list;
 
+  Float32x4List asUnmodifiableView() => this;
+
   Float32x4List _createList(int length) => Float32x4List(length);
 }
 
@@ -517,6 +541,8 @@ final class _UnmodifiableFloat64x2ListView
   final Float64x2List _list;
   _UnmodifiableFloat64x2ListView(Float64x2List list) : _list = list;
 
+  Float64x2List asUnmodifiableView() => this;
+
   Float64x2List _createList(int length) => Float64x2List(length);
 }
 
@@ -530,6 +556,8 @@ final class _UnmodifiableFloat32ListView extends UnmodifiableListBase<double>
   final Float32List _list;
   _UnmodifiableFloat32ListView(Float32List list) : _list = list;
 
+  Float32List asUnmodifiableView() => this;
+
   Float32List _createList(int length) => Float32List(length);
 }
 
@@ -543,6 +571,8 @@ final class _UnmodifiableFloat64ListView extends UnmodifiableListBase<double>
   final Float64List _list;
   _UnmodifiableFloat64ListView(Float64List list) : _list = list;
 
+  Float64List asUnmodifiableView() => this;
+
   Float64List _createList(int length) => Float64List(length);
 }
 

sdk/lib/_internal/js_dev_runtime/private/native_typed_data.dart

@@ -162,6 +162,8 @@ final class NativeFloat32x4List extends Object
     _storage[(index * 4) + 3] = value.w;
   }
 
+  Float32x4List asUnmodifiableView() => UnmodifiableFloat32x4ListView(this);
+
   Float32x4List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     return NativeFloat32x4List._externalStorage(
@@ -234,6 +236,8 @@ final class NativeInt32x4List extends Object
     _storage[(index * 4) + 3] = value.w;
   }
 
+  Int32x4List asUnmodifiableView() => UnmodifiableInt32x4ListView(this);
+
   Int32x4List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     return NativeInt32x4List._externalStorage(
@@ -300,6 +304,8 @@ final class NativeFloat64x2List extends Object
     _storage[(index * 2) + 1] = value.y;
   }
 
+  Float64x2List asUnmodifiableView() => UnmodifiableFloat64x2ListView(this);
+
   Float64x2List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     return NativeFloat64x2List._externalStorage(
@@ -407,6 +413,8 @@ final class NativeByteData extends NativeTypedData implements ByteData {
 
   int get elementSizeInBytes => 1;
 
+  ByteData asUnmodifiableView() => UnmodifiableByteDataView(this);
+
   /// Returns the floating point number represented by the four bytes at
   /// the specified [byteOffset] in this object, in IEEE 754
   /// single-precision binary floating-point format (binary32).
@@ -757,6 +765,8 @@ final class NativeFloat32List extends NativeTypedArrayOfDouble
 
   Type get runtimeType => Float32List;
 
+  Float32List asUnmodifiableView() => UnmodifiableFloat32ListView(this);
+
   Float32List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     var source =
@@ -789,6 +799,8 @@ final class NativeFloat64List extends NativeTypedArrayOfDouble
 
   Type get runtimeType => Float64List;
 
+  Float64List asUnmodifiableView() => UnmodifiableFloat64ListView(this);
+
   Float64List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     var source = JS('NativeFloat64List', '#.subarray(#, #)', this, start, stop);
@@ -824,6 +836,8 @@ final class NativeInt16List extends NativeTypedArrayOfInt implements Int16List {
     return JS<int>('!', '#[#]', this, index);
   }
 
+  Int16List asUnmodifiableView() => UnmodifiableInt16ListView(this);
+
   Int16List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     var source = JS('NativeInt16List', '#.subarray(#, #)', this, start, stop);
@@ -859,6 +873,8 @@ final class NativeInt32List extends NativeTypedArrayOfInt implements Int32List {
     return JS<int>('!', '#[#]', this, index);
   }
 
+  Int32List asUnmodifiableView() => UnmodifiableInt32ListView(this);
+
   Int32List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     var source =
@@ -895,6 +911,8 @@ final class NativeInt8List extends NativeTypedArrayOfInt implements Int8List {
     return JS<int>('!', '#[#]', this, index);
   }
 
+  Int8List asUnmodifiableView() => UnmodifiableInt8ListView(this);
+
   Int8List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     var source = JS<NativeInt8List>('!', '#.subarray(#, #)', this, start, stop);
@@ -934,6 +952,8 @@ final class NativeUint16List extends NativeTypedArrayOfInt
     return JS<int>('!', '#[#]', this, index);
   }
 
+  Uint16List asUnmodifiableView() => UnmodifiableUint16ListView(this);
+
   Uint16List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     var source =
@@ -971,6 +991,8 @@ final class NativeUint32List extends NativeTypedArrayOfInt
     return JS<int>('!', '#[#]', this, index);
   }
 
+  Uint32List asUnmodifiableView() => UnmodifiableUint32ListView(this);
+
   Uint32List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     var source =
@@ -1010,6 +1032,9 @@ final class NativeUint8ClampedList extends NativeTypedArrayOfInt
     return JS<int>('!', '#[#]', this, index);
   }
 
+  Uint8ClampedList asUnmodifiableView() =>
+      UnmodifiableUint8ClampedListView(this);
+
   Uint8ClampedList sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     var source =
@@ -1060,6 +1085,8 @@ final class NativeUint8List extends NativeTypedArrayOfInt implements Uint8List {
     return JS<int>('!', '#[#]', this, index);
   }
 
+  Uint8List asUnmodifiableView() => UnmodifiableUint8ListView(this);
+
   Uint8List sublist(int start, [int? end]) {
     var stop = _checkValidRange(start, end, this.length);
     var source =