Json_serializable.dart: Json_serializable is not generating *.g.dart files

[SwissCheese5]

Given this class:

import 'dart:typed_data';

import 'package:meta/meta.dart';
import 'package:json_annotation/json_annotation.dart';

part 'entities.g.dart';

@JsonSerializable(nullable: false)
class User {
  final String uid;
  final String email;
  final String displayName;
  final String profilePicture;
  final String accountType;

  User(
      {@required this.uid,
      @required this.email,
      @required this.displayName,
      @required this.profilePicture,
      this.accountType});

  factory User.fromJson(Map<String, dynamic> json) => _$UserFromJson(json);

  Map<String, dynamic> toJson() => _$UserToJson(this);
}

(Image so you can see what my IDE is highlighting)

This is inside a dart file called entities.dart

This is my pubspec.yaml

name: <...>
description: <...>

version: 1.0.0+1

environment:
  sdk: ">=2.6.0 <3.0.0"

dependencies:
  flutter:
    sdk: flutter

  google_sign_in: ^4.4.3
  firebase_auth: ^0.16.0
  firebase_core: ^0.4.4+3
  cloud_firestore: ^0.13.5
  google_fonts: ^1.0.0
  json_annotation: ^3.0.1
  provider: ^4.0.5
  url_launcher: ^5.4.5
  image_picker: ^0.6.5+2
  image_picker_web: ^1.0.6
  string_validator: ^0.1.4
  intl_phone_number_input: ^0.3.0
  currency_pickers: ^1.0.6
  i18n_extension: ^1.3.5
  photo_view: ^0.9.2

dev_dependencies:
  build_runner: ^1.9.0
  json_serializable: ^3.3.0
  flutter_test:
    sdk: flutter
  flutter_localizations:
    sdk: flutter

flutter:
  uses-material-design: true
  assets:
    - assets/

I am running the following command:
flutter packages pub run build_runner build

And this is the console output:

[INFO] Generating build script...
[INFO] Generating build script completed, took 384ms

[INFO] Initializing inputs
[INFO] Reading cached asset graph...
[INFO] Reading cached asset graph completed, took 75ms

[INFO] Checking for updates since last build...
[INFO] Checking for updates since last build completed, took 741ms

[INFO] Running build...
[INFO] Running build completed, took 18ms

[INFO] Caching finalized dependency graph...
[INFO] Caching finalized dependency graph completed, took 51ms

[INFO] Succeeded after 88ms with 0 outputs (0 actions)

I've tried many variations of the class, it simply wont generate anything.

I've tried a non-optional constructor, removing @required, changing imports, renaming the dart file, invalidating caches and restarting several times, renaming the class, etc...

[he36251]

Try on line 6

part 'User.g.dart';

and rename the file to User.dart.

[kevmoo]

Try on line 6

part 'User.g.dart';

and rename the file to User.dart.

user.dart – always use lower case file names!

[kevmoo]

Where is this file located in your package?

[SwissCheese5]

@kevmoo

[kevmoo]

Try deleting .dart_tool/build first then running build again...

[natebosch]

Can you look at the .dart_tool/build/entrypoint/build.dart and see if there is an .apply call for the json serializable and source_gen builders?

[SwissCheese5]

@natebosch
This is my .dart_tool/build/entrypoint/build.dart

// ignore_for_file: directives_ordering

import 'package:build_runner_core/build_runner_core.dart' as _i1;
import 'package:json_serializable/builder.dart' as _i2;
import 'package:source_gen/builder.dart' as _i3;
import 'package:build_config/build_config.dart' as _i4;
import 'dart:isolate' as _i5;
import 'package:build_runner/build_runner.dart' as _i6;
import 'dart:io' as _i7;

final _builders = <_i1.BuilderApplication>[
  _i1.apply('json_serializable:json_serializable', [_i2.jsonSerializable],
      _i1.toDependentsOf('json_serializable'),
      hideOutput: true, appliesBuilders: ['source_gen:combining_builder']),
  _i1.apply('source_gen:combining_builder', [_i3.combiningBuilder],
      _i1.toNoneByDefault(),
      hideOutput: false, appliesBuilders: ['source_gen:part_cleanup']),
  _i1.applyPostProcess('source_gen:part_cleanup', _i3.partCleanup,
      defaultGenerateFor: const _i4.InputSet())
];
void main(List<String> args, [_i5.SendPort sendPort]) async {
  var result = await _i6.run(args, _builders);
  sendPort?.send(result);
  _i7.exitCode = result;
}

@kevmoo
Deleted .dart_tool/build Rerun the build method, it did not fix the issue.

[INFO] Generating build script...
[INFO] Generating build script completed, took 443ms

[INFO] Initializing inputs
[INFO] Reading cached asset graph...
[INFO] Reading cached asset graph completed, took 86ms

[INFO] Checking for updates since last build...
[INFO] Checking for updates since last build completed, took 861ms

[INFO] Running build...
[INFO] Running build completed, took 19ms

[INFO] Caching finalized dependency graph...
[INFO] Caching finalized dependency graph completed, took 64ms

[INFO] Succeeded after 93ms with 0 outputs (0 actions)

[natebosch]

What is your project layout? Is api/entities.dart under lib/ somewhere? It should be...

[SwissCheese5]

@natebosch https://github.com/dart-lang/json_serializable/issues/636#issuecomment-620789621

I answered this already above. lib/api/entities.

[natebosch]

Deleted .dart_tool/build Rerun the build method, it did not fix the issue.

The output you pasted isn't from the attempt immediately after deleting this directory. Could you show us that output?

[SwissCheese5]

@natebosch What? It was the attempt directly after...
Step by step: i deleted the /build folder, I showed you a screenshot of the directory with /build missing, then I ran the same command (flutter packages pub run build_runner build) and copied the output from my console and pasted it here.
I even invalidated caches in intellij and tried again with the exact same output.

Again, here is a screenshot of .dart_tool in my project folder as well as the entire project structure (blurred project name):

And here is the output that you see in the screenshot:

[INFO] Generating build script...
[INFO] Generating build script completed, took 405ms

[INFO] Initializing inputs
[INFO] Reading cached asset graph...
[INFO] Reading cached asset graph completed, took 81ms

[INFO] Checking for updates since last build...
[INFO] Checking for updates since last build completed, took 766ms

[INFO] Running build...
[INFO] Running build completed, took 19ms

[INFO] Caching finalized dependency graph...
[INFO] Caching finalized dependency graph completed, took 62ms

[INFO] Succeeded after 91ms with 0 outputs (0 actions)

[jakemac53]

Can you try running flutter packages pub run build_runner clean? The build above was a cached build.

Then if you can flutter packages pub run build_runner build --verbose that might help although it will be... noisy ;).

[SwissCheese5]

@jakemac53

<...>flutter packages pub run build_runner clean
[WARNING] Deleting cache and generated source files.
This shouldn't be necessary for most applications, unless you have made intentional edits to generated files (i.e. for testing). Consider filing a bug at https://github.com/dart-lang/build/issues/new if you are using this to work around an apparent (and reproducibl
e) bug.
[INFO] Cleaning up source outputs...
[INFO] Cleaning up source outputs completed, took 158ms

[INFO] Cleaning up cache directory...
[INFO] Cleaning up cache directory completed, took 6ms


<...>flutter packages pub run build_runner build --verbose
[INFO] Generating build script...
[INFO] Generating build script completed, took 395ms

[INFO] Creating build script snapshot......
[INFO] Creating build script snapshot... completed, took 12.1s

[INFO] BuildDefinition:Initializing inputs
[INFO] BuildDefinition:Building new asset graph...
[INFO] BuildDefinition:Building new asset graph completed, took 711ms

[INFO] BuildDefinition:Checking for unexpected pre-existing outputs....
[INFO] BuildDefinition:Checking for unexpected pre-existing outputs. completed, took 1ms

[INFO] Build:Running build...
[INFO] Heartbeat:1.1s elapsed, 0/7 actions completed.
[INFO] Heartbeat:2.2s elapsed, 0/7 actions completed.
[INFO] Heartbeat:3.3s elapsed, 0/7 actions completed.
[INFO] Heartbeat:6.2s elapsed, 0/7 actions completed.
[INFO] Heartbeat:7.2s elapsed, 0/7 actions completed.
[FINE] json_serializable:json_serializable on lib/api/entities.dart:Running JsonSerializableGenerator - 1 of 2
[FINE] json_serializable:json_serializable on lib/api/entities.dart:Running JsonLiteralGenerator - 2 of 2
[FINE] json_serializable:json_serializable on lib/theme_mode_notifier.dart:Running JsonSerializableGenerator - 1 of 2
[FINE] json_serializable:json_serializable on lib/theme_mode_notifier.dart:Running JsonLiteralGenerator - 2 of 2
[FINE] json_serializable:json_serializable on lib/api/firebase.dart:Running JsonSerializableGenerator - 1 of 2
[FINE] json_serializable:json_serializable on lib/api/firebase.dart:Running JsonLiteralGenerator - 2 of 2
[FINE] json_serializable:json_serializable on lib/generated_plugin_registrant.dart:Running JsonSerializableGenerator - 1 of 2
[FINE] json_serializable:json_serializable on lib/generated_plugin_registrant.dart:Running JsonLiteralGenerator - 2 of 2
[FINE] json_serializable:json_serializable on lib/main.dart:Running JsonSerializableGenerator - 1 of 2
[FINE] json_serializable:json_serializable on lib/main.dart:Running JsonLiteralGenerator - 2 of 2
[FINE] json_serializable:json_serializable on lib/user_entry_page.dart:Running JsonSerializableGenerator - 1 of 2
[FINE] json_serializable:json_serializable on lib/user_entry_page.dart:Running JsonLiteralGenerator - 2 of 2
[FINE] json_serializable:json_serializable on test/widget_test.dart:Running JsonSerializableGenerator - 1 of 2
[FINE] json_serializable:json_serializable on test/widget_test.dart:Running JsonLiteralGenerator - 2 of 2
[INFO] Build:Running build completed, took 13.5s

[INFO] Build:Caching finalized dependency graph...
[INFO] Build:Caching finalized dependency graph completed, took 38ms

[INFO] Build:Succeeded after 13.6s with 2 outputs (15 actions)

No difference:

[jakemac53]

Ok - so this time it did at least run on the file as you can see in the logs - and there was some output (2 files).

If you look under .dart_tool/build/generated/<your-package>/lib/api/ do you see any files? Or do you not have any .dart_tool/build dir at all somehow?

[SwissCheese5]

@jakemac53 as you can see in the screenshot, .dart_tool/build does not exist

Here's the file explorer screenshot as proof that it is not my IDE screwing it up

[jakemac53]

Are you sure that the file explorer doesn't need to be refreshed? I don't know about intellij but in vscode sometimes you have to do that.

[jakemac53]

Oh nvm I see this last screenshot is from a different file explorer.

[jakemac53]

That is extremely confusing because .dart_tool/build is where everything the build system creates is put. So, I have no idea where it could be if it is not there. Even the generated build script itself is there.

[jakemac53]

what path does flutter packages pub run build_runner generate-build-script print out? Does it match your current package directory?

[jakemac53]

And to confirm after you run that command the file does or does not exist?

[SwissCheese5]

Hmm, I think it's a different path. I will debug and reply later with my findings. I'll be a while, not going to do it now

[jakemac53]

Ok, what it sounds like to me is the the current working directory (at least as reported to build_runner by the Dart vm), is not the root of the package you think you are running from. It is building some different package somewhere.

[AlexisBrgn]

Did you try to have matching class name, filename and part name?
Some people reported success on stack exchange and I faced the same problem and doing so solved it.

User.dart

part 'User.g.dart';

@JsonSerializable(nullable: false)
class User {
  final String uid;
  final String email;
  final String displayName;
  final String profilePicture;
  final String accountType;

  User(
      {@required this.uid,
      @required this.email,
      @required this.displayName,
      @required this.profilePicture,
      this.accountType});

  factory User.fromJson(Map<String, dynamic> json) => _$UserFromJson(json);

  Map<String, dynamic> toJson() => _$UserToJson(this);
}

[SwissCheese5]

It seems intellij's built in terminal was using a different directory than the current one. So that was the issue.