Introduction

A Dart CLI tool for analyzer-based, extremely fast, and clean data class code generation.

Parses Dart code into an AST using only the Dart analyzer, building classes completely independently of build_runner, achieving unparalleled build speed (🚀 Takes 5 ~ 10ms per file on average).

Support

🟢 Supported 🟡 Planned 🔴 Not Supported

Future	Status	Usage
🔒 Immutability	🟢	It's still required
🗝️ Private fields	🟢	Support private fields with getters.
🔄 copyWith (Clone)	🟢	@Datagen(copyWith: true)
📦 JSON serialization	🟢	@Datagen(fromJson: true, fromJsonList: true, toJson: true)
📝 Stringify	🟢	@Datagen(stringify: true)
⚖️ Equality	🟢	@Datagen(equality: true)

Preview

Development

When developing, there’s no need to follow any special format like freezed or mappable. As long as you write proper const constructors, the Datagen library builder will automatically adjust the code to fit standard Dart conventions. Also, it’s highly recommended to use the watch feature during development!

Usage

Learn how to quickly set up and use this library for generating data classes.

Annotate Your Class

The following is an example of using the @datagen or @Datagen() annotation on a class.

Applying this annotation enables Datagen to generate utility features such as copyWith, JSON serialization, stringify, and equality overrides based on the configuration options.

@Datagen(omitFactory: true)
class A {
  const A({
    required String name,
    int age = 20,
    DateTime? dateTime,
    required dynamic status,

    // Specifies the target type to convert the field to using `@Get`.
    // Only needs to indicate the target type and the actual type in the data class.
    @Get(int) required String minute,
  });

  // Use `dynamic` and a custom getter for fields not supported by `@Get`, 
  // e.g., the `status` field may require custom conversion.
  @override
  Enum get status {...}
}

Build the Data Class

Generate the code using:

dart run datagen build

Using Watch Mode

Automatically rebuild on file changes:

dart run datagen watch

Options

Arguments for the @Datagen() annotation.

Name	Description	Default
copyWith	Enables generating a copyWith method for the annotated class.	true
fromJson	Enables generating a fromJson factory constructor.	true
toJson	Enables generating a toJson method.	true
stringify	Enables generating a toString override method.	true
equality	Enables generating a hashCode and operator == override.	true
omitFactory	Controls whether a fromJson factory is generated in the public class. The factory in the generated .datagen.dart class is always created.	false

How to Set Config File?

Create a file named datagen.json in the folder where you run the CMD command, and write the following configuration inside:

{
    "options": {
        "copyWith": true,
        "fromJson": true,
        "fromJsonList": true,
        "toJson": true,
        "stringify": true,
        "omitFactory": false
    },
    "useCommand": true
}

IDE Settings Guide

This table provides quick access to IDE-specific tips and guides.

IDE	Docs
Visual Studio Code	VSCODE_GUIDE.md