如何修复颤振build_runner错误:未能预编译build_runner:build_runner：

Question

我正在处理两个颤振项目，其中一个已经迁移到空安全，并使用了Flutter 2.0.5。导致问题的第二个项目还没有迁移到空安全，而是使用了Flutter 1.22.6。切换项目是通过重命名颤振SDK文件夹完成的。

现在的问题是，build_runner只适用于颤振2.0.5。当从flutter pub run build_runner build Flutter 1.22.6项目内部调用时，它将失败，其中包含以下错误消息：

Failed to precompile build_runner:build_runner:
../../../Flutter%20SDK/flutter/.pub-cache/hosted/pub.dartlang.org/http_multi_server-2.1.0/lib/src/multi_headers.dart:97:8: Error: The method 'MultiHeaders.add' has fewer named arguments than those of overridden method 'HttpHeaders.add'.
  void add(String name, Object value) {
       ^
org-dartlang-sdk:///sdk/lib/_http/http.dart:698:8: Context: This is the overridden method ('add').
  void add(String name, Object value,
       ^
../../../Flutter%20SDK/flutter/.pub-cache/hosted/pub.dartlang.org/http_multi_server-2.1.0/lib/src/multi_headers.dart:129:8: Error: The method 'MultiHeaders.set' has fewer named arguments than those of overridden method 'HttpHeaders.set'.
  void set(String name, Object value) {
       ^
org-dartlang-sdk:///sdk/lib/_http/http.dart:707:8: Context: This is the overridden method ('set').
  void set(String name, Object value,
       ^
../../../Flutter%20SDK/flutter/.pub-cache/hosted/pub.dartlang.org/build_runner-1.11.0/lib/src/entrypoint/runner.dart:23:31: Error: No named parameter with the name 'usageLineLength'.
  final argParser = ArgParser(usageLineLength: lineLength);
                              ^^^^^^^^^^^^^^^
../../../Flutter%20SDK/flutter/.pub-cache/hosted/pub.dartlang.org/args-1.4.4/lib/src/arg_parser.dart:43:11: Context: Found this candidate, but the arguments don't match.
  factory ArgParser({bool allowTrailingOptions: true}) =>
          ^
../../../Flutter%20SDK/flutter/.pub-cache/hosted/pub.dartlang.org/build_runner-1.11.0/bin/src/commands/clean.dart:18:31: Error: No named parameter with the name 'usageLineLength'.
  final argParser = ArgParser(usageLineLength: lineLength);
                              ^^^^^^^^^^^^^^^
../../../Flutter%20SDK/flutter/.pub-cache/hosted/pub.dartlang.org/args-1.4.4/lib/src/arg_parser.dart:43:11: Context: Found this candidate, but the arguments don't match.
  factory ArgParser({bool allowTrailingOptions: true}) =>
          ^
../../../Flutter%20SDK/flutter/.pub-cache/hosted/pub.dartlang.org/build_runner-1.11.0/bin/src/commands/generate_build_script.dart:18:31: Error: No named parameter with the name 'usageLineLength'.
  final argParser = ArgParser(usageLineLength: lineLength);
                              ^^^^^^^^^^^^^^^
../../../Flutter%20SDK/flutter/.pub-cache/hosted/pub.dartlang.org/args-1.4.4/lib/src/arg_parser.dart:43:11: Context: Found this candidate, but the arguments don't match.
  factory ArgParser({bool allowTrailingOptions: true}) =>

奇怪的是，所有这些错误都在项目之外。调用flutter clean和flutter pub cache repair没有任何影响。所以问题是，要让build_runner运行(现在已经过时的) Flutter version 1.22.6，需要做些什么？非常欢迎您的建议，谢谢！

Answer 1

由于所需的第三方库阻止迁移到空安全，唯一的解决方案是通过从生成的json切换到手工编写的build_runner来消除json。

与其说是一种解决方案，不如说是一种解决办法，但它已经足够了。