Upgrade tests to use Xcode 16 and iOS 18 (#8968)

Fixes flutter/flutter#148956.

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Author: vashworth

.ci.yaml

@@ -90,25 +90,25 @@ platform_properties:
         [
           {"dependency": "ruby", "version": "ruby_3.1-pod_1.13"}
         ]
-      os: Mac-13|Mac-14
+      os: Mac-14
       device_type: none
       cpu: arm64
       $flutter/osx_sdk : >-
         {
-          "sdk_version": "15a240d"
+          "sdk_version": "16c5032a"
         }
   mac_x64:
     properties:
       dependencies: >-
         [
           {"dependency": "ruby", "version": "ruby_3.1-pod_1.13"}
         ]
-      os: Mac-13|Mac-14
+      os: Mac-14
       device_type: none
       cpu: x86
       $flutter/osx_sdk : >-
         {
-          "sdk_version": "15a240d"
+          "sdk_version": "16c5032a"
         }
 
 targets:

.ci/scripts/create_simulator.sh

@@ -9,7 +9,7 @@ set -o pipefail
 # The name here must match remove_simulator.sh
 readonly DEVICE_NAME=Flutter-iPhone
 readonly DEVICE=com.apple.CoreSimulator.SimDeviceType.iPhone-14
-readonly OS=com.apple.CoreSimulator.SimRuntime.iOS-17-0
+readonly OS=com.apple.CoreSimulator.SimRuntime.iOS-18-2
 
 # Delete any existing devices named Flutter-iPhone. Having more than one may
 # cause issues when builds target the device.

.ci/targets/ios_platform_tests.yaml

@@ -22,7 +22,7 @@ tasks:
   - name: native test
     script: .ci/scripts/tool_runner.sh
     # Simulator name and version must match name and version in create_simulator.sh
-    args: ["native-test", "--ios", "--ios-destination", "platform=iOS Simulator,name=Flutter-iPhone,OS=17.0", "--xcode-warnings-exceptions=script/configs/xcode_warnings_exceptions.yaml"]
+    args: ["native-test", "--ios", "--ios-destination", "platform=iOS Simulator,name=Flutter-iPhone,OS=18.2", "--xcode-warnings-exceptions=script/configs/xcode_warnings_exceptions.yaml"]
   - name: boot simulator
     # Ensure simulator is still booted
     script: .ci/scripts/boot_simulator.sh

packages/pigeon/tool/shared/test_suites.dart

@@ -305,8 +305,8 @@ Future<int> _runIOSPluginUnitTests(String testPluginPath) async {
 
   const String deviceName = 'Pigeon-Test-iPhone';
   const String deviceType = 'com.apple.CoreSimulator.SimDeviceType.iPhone-14';
-  const String deviceRuntime = 'com.apple.CoreSimulator.SimRuntime.iOS-17-0';
-  const String deviceOS = '17.0';
+  const String deviceRuntime = 'com.apple.CoreSimulator.SimRuntime.iOS-18-2';
+  const String deviceOS = '18.2';
   await _createSimulator(deviceName, deviceType, deviceRuntime);
   return runXcodeBuild(
     '$examplePath/ios',