Objectbox 生成器有关问题的详细信息？

编程问答 2022-04-30

问题描述

当我使用 Flutter packages pub run build_runner watch 运行 objectBox_generator 时，类是在 JSON 中生成的，但不久之后由于空检查问题，生成失败。我检查了我的代码，但找不到任何空检查问题。有没有办法显示更详细的日志（例如它所在的位置）？

[INFO] Starting Build

[INFO] Updating asset graph...
[INFO] Updating asset graph completed,took 0ms

[INFO] Running build...
[INFO] 1.0s elapsed,14/20 actions completed.
[INFO] 2.1s elapsed,38/54 actions completed.
[INFO] Running build completed,took 2.4s

[INFO] Caching finalized dependency graph...
[INFO] Caching finalized dependency graph completed,took 100ms

// Here the failing info

[SEVERE] objectBox_generator:generator on lib/$lib$ (cached):

Null check operator used on a null value

[SEVERE] Failed after 2.5s

具有附加信息的相同命令 Flutter packages pub run build_runner build --verbose：

[INFO] Build:Running build...
[INFO] objectBox_generator:generator on lib/$lib$:Package: fit_x
[INFO] objectBox_generator:generator on lib/$lib$:Found 15 entities in: (lib/domain/ob/collection_exercise.objectBox.info,lib/domain/ob/equipment.objectBox.info,lib/domain/ob/equipment_setting.objectBox.info,...,lib/domain/ob/workout_collection.objectBox.info,lib/domain/ob/workout_log.objectBox.info)
[INFO] objectBox_generator:generator on lib/$lib$:Using model: lib/objectBox-model.json
[SEVERE] objectBox_generator:generator on lib/$lib$:

Null check operator used on a null value
package:objectBox_generator/src/code_chunks.dart 444:38  CodeChunks.backlinkRelInfo
package:objectBox_generator/src/code_chunks.dart 488:18  CodeChunks.toManyRelations.<fn>
dart:_internal                                           ListIterable.join
package:objectBox_generator/src/code_chunks.dart 489:12  CodeChunks.toManyRelations
package:objectBox_generator/src/code_chunks.dart 134:46  CodeChunks.entityBinding
package:objectBox_generator/src/code_chunks.dart 32:71   CodeChunks.objectBoxDart.<fn>
package:collection/src/iterable_extensions.dart 173:20   IterableExtension.mapIndexed
dart:core                                                Iterable.join
package:objectBox_generator/src/code_chunks.dart 32:99   CodeChunks.objectBoxDart
package:objectBox_generator/src/code_builder.dart 97:27  CodeBuilder.updateCode
package:objectBox_generator/src/code_builder.dart 57:5   CodeBuilder.build

[INFO] Build:Running build completed,took 349ms

[INFO] Build:Caching finalized dependency graph...
[INFO] Build:Caching finalized dependency graph completed,took 117ms

[SEVERE] Build:
Failed after 476ms
[+3823 ms] "Flutter run" took 3.927ms.
[   +5 ms] pub finished with exit code 1
[   +2 ms] 
           #0      throwToolExit (package:Flutter_tools/src/base/common.dart:10:3)
           #1      _DefaultPub.interactively (package:Flutter_tools/src/dart/pub.dart:366:7)
           <asynchronous suspension>
           #2      PackagesForwardCommand.runcommand (package:Flutter_tools/src/commands/packages.dart:241:5)
           <asynchronous suspension>
           #3      FlutterCommand.run.<anonymous closure> (package:Flutter_tools/src/runner/Flutter_command.dart:1043:27)
           <asynchronous suspension>
           #4      AppContext.run.<anonymous closure> (package:Flutter_tools/src/base/context.dart:150:19)
           <asynchronous suspension>
           #5      CommandRunner.runcommand (package:args/command_runner.dart:196:13)
           <asynchronous suspension>
           #6      FlutterCommandRunner.runcommand.<anonymous closure> (package:Flutter_tools/src/runner/Flutter_command_runner.dart:284:9)    
           <asynchronous suspension>
           #7      AppContext.run.<anonymous closure> (package:Flutter_tools/src/base/context.dart:150:19)
           <asynchronous suspension>
           #8      FlutterCommandRunner.runcommand (package:Flutter_tools/src/runner/Flutter_command_runner.dart:232:5)
           <asynchronous suspension>
           #9      run.<anonymous closure>.<anonymous closure> (package:Flutter_tools/runner.dart:62:9)
           <asynchronous suspension>
           #10     AppContext.run.<anonymous closure> (package:Flutter_tools/src/base/context.dart:150:19)
           <asynchronous suspension>
           #11     main (package:Flutter_tools/executable.dart:91:3)
           <asynchronous suspension>


[  +74 ms] ensureAnalyticsSent: 67ms
[   +1 ms] Running shutdown hooks
[        ] Shutdown hooks complete
[        ] exiting with code 1

解决方法

从代码看来，您有一个 @Backlink() 到未知实体（未存储在数据库中的实体）...尝试检查这些反向链接（并将它们注释掉以查看是否有效）当你发现哪个触发了这个，考虑在 objectbox-dart 的 GitHub 上用最小的例子打开一个问题。

P。 S. 至于空检查失败 - 是的，需要一个更好的错误（一个告诉你缺少实体的错误） - https://github.com/objectbox/objectbox-dart/commit/00aabe224eaa9bb88ab2bc18a5c31f00b4f3bdc0

build-runnerdartgeneratorgeneratorobjectbox