generator_test 0.1.0

A library to help test generators and build runner packages using dart files instead of Strings

Generator Test

A library to help test generators and build runner packages using dart files instead of Strings

Purpose

Testing generators and build_runner packages can be difficult. generator_test is a library aimed at making it easier to accomplish this!

Usage

Depend on it

Add generator_test to your pubspec.yaml

dev_dependencies:
  generator_test: # RECENT_VERSION

Use it

Create a fixture file

A fixture is

A known state which a test is running against

Meaning, you can create an "output" to compare against the generated code based on a specific input. You can read more about it here

To use this package, you will create files, an input & a fixture file (aka the expected generated output).

Here is an example of what your input file could look like

part 'fixtures/example.dart';

@ClassName()
class Example {}

And here is an example of what your fixture file could look like

part of '../example.dart';

// **************************************************************************
// ClassNameGenerator
// **************************************************************************

// The class name is `Example`

The generator_test package will handle the files parts for you, whether it should be included or not, and the extension to be used based on the builder being tested.

Take Note:
You must include the generator's (class) name, enclosed in ***, within the fixture file

Create your test

Generator

// create the test generator

final generator = SuccessGenerator(
      'example',
      ClassNameGenerator(),
      inputDir: 'test/fixture', // default
      fixtureDir: 'test/fixture/fixtures', // default
      compareWithFixture: true, // use `false` to validate dart code only
      fixtureFileName: ..., // used when fixture file name does not match input file name
    );
);

// run the test
generator.test();

Builder

final generator = SuccessGenerator.fromBuilder(
      'example',
      classNameBuilder, // entry point for the build_runner
      inputDir: 'test/fixture', // default
      fixtureDir: 'test/fixture/fixtures', // default
      compareWithFixture: true, // use `false` to validate dart code only
      fixtureFileName: ..., // used when fixture file name does not match input file name
      extension: ..., // retrieves from the builder ie: .g.dart
      options: ..., // config for your builder ie: {'add_comment': true}
    );

// run the test
generator.test();

Debug Bonus

Debugging build_runners is not s simple task, and on top of that, the analyzer's api is HUGE. It can be daunting to write build_runner packages with the amount of data you need to filter through to get the values you want.

generator_test makes it possible to add break points during your tests, which makes developing build_runner packages much easier!

Simply add async/await to your test and run in debug mode!

void main(){
  test('generates successfully', () async {
    final generator = SuccessGenerator.fromBuilder(
          'example',
          classNameBuilder,
          compareWithFixture: false, // use `false` to validate dart code
        );

    // dubug your package
    await generator.test();
  });
}

Find the values you're looking for!