[objective_c] Move test/util.c to helper package (objective_c_helper)

pkgs/objective_c/hook/build.dart

@@ -15,7 +15,6 @@ const assetName = 'objective_c.dylib';
 
 // TODO(https://github.com/dart-lang/native/issues/2272): Remove this from the
 // main build.
-const testFiles = ['test/util.c'];
 
 final logger = Logger('')
   ..level = Level.INFO
@@ -59,14 +58,6 @@ void main(List<String> args) async {
       }
     }
 
-    // Only include the test utils on mac OS. They use memory functions that
-    // aren't supported on iOS, like mach_vm_region. We don't need them on iOS
-    // anyway since we only run memory tests on mac.
-    if (os == OS.macOS) {
-      cFiles.addAll(
-        testFiles.map((f) => input.packageRoot.resolve(f).toFilePath()),
-      );
-    }
 
     final sysroot = sdkPath(codeConfig);
     final minVersion = minOSVersion(codeConfig);

pkgs/objective_c/pubspec.yaml

@@ -45,3 +45,5 @@ dependency_overrides:
     path: ../hooks
   native_toolchain_c:
     path: ../native_toolchain_c
+  objective_c_helper:
+    path: ../objective_c_helper

pkgs/objective_c/test/autorelease_test.dart

@@ -10,7 +10,6 @@ import 'dart:ffi';
 
 import 'package:objective_c/objective_c.dart';
 import 'package:test/test.dart';
-
 import 'util.dart';
 
 void main() {

pkgs/objective_c/test/interface_lists_test.dart

@@ -11,7 +11,6 @@ import 'dart:io';
 import 'package:ffigen/src/code_generator/objc_built_in_types.dart';
 import 'package:path/path.dart' as p;
 import 'package:test/test.dart';
-
 import 'util.dart';
 
 // The default expect error message for sets isn't very useful. In the common

pkgs/objective_c/test/nsdictionary_test.dart

@@ -10,7 +10,6 @@ import 'dart:ffi';
 
 import 'package:objective_c/objective_c.dart';
 import 'package:test/test.dart';
-
 import 'util.dart';
 
 void main() {

pkgs/objective_c/test/observer_test.dart

@@ -10,7 +10,6 @@ import 'dart:ffi';
 
 import 'package:objective_c/objective_c.dart';
 import 'package:test/test.dart';
-
 import 'util.dart';
 
 void main() {

pkgs/objective_c/test/util.dart

@@ -32,37 +32,4 @@ void doGC() {
   calloc.free(gcNow);
 }
 
-@Native<Int Function(Pointer<Void>)>(isLeaf: true, symbol: 'isReadableMemory')
-external int _isReadableMemory(Pointer<Void> ptr);
-
-@Native<Uint64 Function(Pointer<Void>)>(
-  isLeaf: true,
-  symbol: 'getObjectRetainCount',
-)
-external int _getObjectRetainCount(Pointer<Void> object);
-
-int objectRetainCount(Pointer<ObjCObjectImpl> object) {
-  if (_isReadableMemory(object.cast()) == 0) return 0;
-  final header = object.cast<Uint64>().value;
-
-  // package:objective_c's isValidObject function internally calls
-  // object_getClass then isValidClass. But object_getClass can occasionally
-  // crash for invalid objects. This masking logic is a simplified version of
-  // what object_getClass does internally. This is less likely to crash, but
-  // more likely to break due to ObjC runtime updates, which is a reasonable
-  // trade off to make in tests where we're explicitly calling it many times
-  // on invalid objects. In package:objective_c's case, it doesn't matter so
-  // much if isValidObject crashes, since it's a best effort attempt to give a
-  // nice stack trace before the real crash, but it would be a problem if
-  // isValidObject broke due to a runtime update.
-  // These constants are the ISA_MASK macro defined in runtime/objc-private.h.
-  const maskX64 = 0x00007ffffffffff8;
-  const maskArm = 0x0000000ffffffff8;
-  final mask = Abi.current() == Abi.macosX64 ? maskX64 : maskArm;
-  final clazz = Pointer<ObjCObjectImpl>.fromAddress(header & mask);
-
-  if (!internal_for_testing.isValidClass(clazz)) return 0;
-  return _getObjectRetainCount(object.cast());
-}
-
 String pkgDir = findPackageRoot('objective_c').toFilePath();

pkgs/objective_c_helper/lib/src/util.dart

@@ -0,0 +1,37 @@
+import 'dart:ffi';
+import 'package:objective_c/objective_c.dart';
+import 'package:objective_c/src/internal.dart' as internal_for_testing show isValidClass;
+
+@Native<Int Function(Pointer<Void>)>(isLeaf: true, symbol: 'isReadableMemory')
+external int _isReadableMemory(Pointer<Void> ptr);
+
+@Native<Uint64 Function(Pointer<Void>)>(
+  isLeaf: true,
+  symbol: 'getObjectRetainCount',
+)
+external int _getObjectRetainCount(Pointer<Void> object);
+
+int objectRetainCount(Pointer<ObjCObjectImpl> object) {
+  if (_isReadableMemory(object.cast()) == 0) return 0;
+  final header = object.cast<Uint64>().value;
+
+  // package:objective_c's isValidObject function internally calls
+  // object_getClass then isValidClass. But object_getClass can occasionally
+  // crash for invalid objects. This masking logic is a simplified version of
+  // what object_getClass does internally. This is less likely to crash, but
+  // more likely to break due to ObjC runtime updates, which is a reasonable
+  // trade off to make in tests where we're explicitly calling it many times
+  // on invalid objects. In package:objective_c's case, it doesn't matter so
+  // much if isValidObject crashes, since it's a best effort attempt to give a
+  // nice stack trace before the real crash, but it would be a problem if
+  // isValidObject broke due to a runtime update.
+  // These constants are the ISA_MASK macro defined in runtime/objc-private.h.
+  const maskX64 = 0x00007ffffffffff8;
+  const maskArm = 0x0000000ffffffff8;
+  final mask = Abi.current() == Abi.macosX64 ? maskX64 : maskArm;
+  final clazz = Pointer<ObjCObjectImpl>.fromAddress(header & mask);
+
+  if (!internal_for_testing.isValidClass(clazz)) return 0;
+  return _getObjectRetainCount(object.cast());
+}
+

pkgs/objective_c_helper/pubspec.yaml

@@ -0,0 +1,7 @@
+name: objective_c_helper
+description: Helper package for objective_c tests
+version: 0.0.1
+environment:
+  sdk: ">=2.19.0 <3.0.0"
+dependencies: {}
+dev_dependencies: {}