Lower SDK lower bound to 3.0.0 (#5)

.github/workflows/dart.yaml

@@ -14,15 +14,19 @@ permissions: read-all
 
 jobs:
   analyze:
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest]
+        sdk: [dev, stable]
 
     steps:
       # These are the latest versions of the github actions; dependabot will
       # send PRs to keep these up-to-date.
       - uses: actions/checkout@c85c95e3d7251135ab7dc9ce3241c5835cc595a9
       - uses: dart-lang/setup-dart@d6a63dab3335f427404425de0fbfed4686d93c4f
         with:
-          sdk: dev
+          sdk: ${{ matrix.sdk }}
 
       - name: Install dependencies
         run: dart pub get
@@ -39,7 +43,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        sdk: [dev]
+        sdk: [dev, stable]
     steps:
       - uses: actions/checkout@c85c95e3d7251135ab7dc9ce3241c5835cc595a9
       - uses: dart-lang/setup-dart@d6a63dab3335f427404425de0fbfed4686d93c4f

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.2.0
+
+- Lower SDK lower bound to 3.0.0.
+
 ## 0.1.0
 
 - Initial version.

lib/mailbox.dart

@@ -103,11 +103,22 @@ class Mailbox {
   static final _emptyResponse = Uint8List(0);
 
   static Uint8List _toList(Pointer<Uint8> buffer, int length) {
-    return length == 0
-        ? _emptyResponse
-        // We have to ignore sdk_version_since warning due to dartbug.com/53142.
-        // ignore: sdk_version_since
-        : buffer.asTypedList(length, finalizer: malloc.nativeFree);
+    if (length == 0) {
+      return _emptyResponse;
+    }
+
+    // TODO: remove feature detection once 3.1 becomes stable.
+    // ignore: omit_local_variable_types
+    final Uint8List Function(int) asTypedList = buffer.asTypedList;
+    if (asTypedList is Uint8List Function(int,
+        {Pointer<NativeFinalizerFunction> finalizer})) {
+      return asTypedList(length, finalizer: malloc.nativeFree);
+    }
+
+    final result = Uint8List(length);
+    result.setRange(0, length, buffer.asTypedList(length));
+    malloc.free(buffer);
+    return result;
   }
 
   static Pointer<Uint8> _toBuffer(Uint8List list) {

pubspec.yaml

@@ -1,10 +1,10 @@
 name: native_synchronization
 description: Low level synchronization primitives built on dart:ffi.
-version: 0.1.0
+version: 0.2.0
 repository: https://github.com/dart-lang/native_synchronization
 
 environment:
-  sdk: ">=3.1.0-348.0.dev <4.0.0"
+  sdk: ">=3.0.0 <4.0.0"
 
 dependencies:
   ffi: ^2.1.0