更新到最新稳定版本后我尝试运行 flutter
\nError output from Xcode build:\n\xe2\x86\xb3\n ** BUILD FAILED **\n\n\nXcodes output:\n\xe2\x86\xb3\n Writing result bundle at path:\n /var/folders/56/fc0b38hx7dv7ldxkbs9flh_m0000gn/T/flutter_tools.sDq2W5/flutter_ios_build_temp_dirGNvLvF/temporary_xcresult_bundle\n\n /usr/local/Caskroom/flutter/2.5.2/flutter/.pub-cache/hosted/pub.dartlang.org/platform-3.0.0/lib/src/interface/local_platform.dart:46:19: Error: Member not\n found: 'packageRoot'.\n io.Platform.packageRoot; // ignore: deprecated_member_use\n ^^^^^^^^^^^\n \n Command PhaseScriptExecution failed with a nonzero exit code\n note: Using new build system\n note: Planning\n note: Build preparation complete\n note: Building targets in parallel\n\n Result bundle written to path:\n /var/folders/56/fc0b38hx7dv7ldxkbs9flh_m0000gn/T/flutter_tools.sDq2W5/flutter_ios_build_temp_dirGNvLvF/temporary_xcresult_bundle\n\n\nCould not build the application for the simulator.\nError launching application on iPhone 13 Pro.\n我已经尝试过了flutter clean，flutter …