Dart Dev Tools

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Centralized tooling for Dart projects. Consistent interface across projects. Easily configurable.

Motivation

All Dart (https://dartlang.org) projects eventually share a common set of development requirements:

  • Tests (unit, integration, and functional)
  • Code coverage
  • Consistent code formatting
  • Static analysis to detect issues
  • Documentation generation
  • Examples for manual testing/exploration
  • Applying a LICENSE file to all source files
  • Running dart unit tests on Sauce Labs

Together, the Dart SDK and a couple of packages from the Dart team supply the necessary tooling to support the above requirements. But, the usage is inconsistent, configuration is limited to command-line arguments, and you inevitably end up with a slew of shell scripts in the tool/ directory. While this works, it lacks a consistent usage pattern across multiple projects and requires an unnecessary amount of error-prone work to set up.

This package improves on the above process by providing a number of benefits:

Centralized Tooling

By housing the APIs and CLIs for these various dev workflows in a single location, you no longer have to worry about keeping scripts in parity across multiple projects. Simply add the dart_dev package as a dependency, and you're ready to go.

Versioned Tooling

Any breaking changes to the APIs or CLIs within this package will be reflected by an appropriate version bump according to semver. You can safely upgrade your tooling to take advantage of continuous improvements and new features with minimal maintenance.

Separation of Concerns

Every task supported in dart_dev is separated into three pieces:

  1. API - programmatic execution via Dart code.
  2. CLI - script-based execution via the dart_dev executable.
  3. Configuration - singleton configuration instances for simple per-project configuration.

Consistent Interface

By providing a single executable (dart_dev) that supports multiple tasks with standardized options, project developers have a consistent interface for development across all projects that utilize this package. Configuration is handled on a per-project basis via a single Dart file, meaning that you don't have to know anything about a project to run tests or static analysis - you just need to know how to use the dart_dev tool.

Note: This is not a replacement for the tooling provided by the Dart SDK and packages like test or dart_style. Rather, dart_dev is a unified interface for interacting with said tooling in a simplified manner.

Tasks

A task is a single unit of execution within dart_dev. They are identified by a name and may or may not take arguments. Several supported tasks are provided by default. Consumers can supplement the supported tasks with project specific local tasks.

Supported Tasks

  • Tests: runs test suites (unit, integration, and functional) via the test package test runner.
  • Coverage: collects coverage over test suites (unit, integration, and functional) and generates a report. Uses the coverage package.
  • Code Formatting: runs the dartfmt tool from the dart_style package over source code.
  • Static Analysis: runs the dartanalyzer over source code.
  • Documentation Generation: runs the tool from the dartdoc package to generate docs.
  • Serving Examples: uses pub serve to serve the project examples.
  • Applying a License to Source Files: copies a LICENSE file to all applicable files.
  • Generate a test runner file: that allows for faster test execution.
  • Running dart unit tests on Sauce Labs compiles dart unit tests that can be run in the browser and executes them on various platforms using Sauce Labs.

Local Tasks

A local task is a script or program that is discovered by dart_dev. By default, dart dev will recursively look for files in the project level tool directory that match the filename pattern (task_name)_task.(executable_type). Any file matching this pattern is parsed and registered as a task. The task discovery will not follow symlink directories by default. Symlink directory expansion can be enabled using the followSymlinks property in the local configuration field.

Any arguments specified after the local task name are passed to the underlying task process as command line arguments. For instance, pub run dart_dev exampleTask --example-argument 23 would pass the example argument and value as additions to the underlying system command dart exampleTask_task.dart --example-argument 23. This allows the task to parse its arguments independently of dart_dev.

Executable types identify how a given task should execute. Dart and bash scripts are supported out of the box. The set of available executable types can be expanded in the configuration as documented below.

Getting Started

Install dart_dev

Add the following to your pubspec.yaml:

dev_dependencies:
  coverage: "^0.7.3"
  dart_dev: "^1.0.0"
  dart_style: ">=0.1.8 <0.3.0"
  dartdoc: "^0.4.0"
  test: "^0.12.0"

Create an Alias (optional)

Add the following to your bash or zsh profile for convenience:

alias ddev='pub run dart_dev'

Bash Completion

Bash command completion is available and easy to use. You'll want to install dart_dev globally: pub global activate dart_dev.

Add the following to your .bashrc:

eval "$(pub global run dart_dev bash-completion)"

If you are using Bash installed through Homebrew, you'll also need to install the completion machinery with brew install bash-completion. Then make sure something like the following is in your .bashrc file:

if [ -f $(brew --prefix)/etc/bash_completion ]; then
  . $(brew --prefix)/etc/bash_completion
fi

Next time you load a Bash session you'll have basic completions for the ddev alias described above.

Zsh Completion

The Bash completion script will work for Zsh as well, but requires a little configuration. The following lines must all be found somewhere (and in this order, though they needn't be adjacent to one another) in your .zshrc file, or a file sourced from it:

autoload -U compinit
compinit
autoload -U bashcompinit
bashcompinit
eval "$(pub global run dart_dev bash-completion)"

Fish Completion

Symlink or copy the file tool/ddev.fish into ~/.config/fish/completions/ (or wherever your completion scripts live).

The completions expect a function called ddev. To meet this expectation create a new file in ~/.config/fish/functions called ddev.fish and add the following content to the file.

function ddev
  pub run dart_dev $argv
end

Configuration

In order to configure dart_dev for a specific project, run ddev init or pub run dart_dev init to generate the configuration file. This should create a tool/dev.dart file where each task can be configured as needed.

import 'package:dart_dev/dart_dev.dart';

main(args) async {
  // Define the entry points for static analysis.
  config.analyze.entryPoints = ['lib/', 'test/', 'tool/'];

  // Define the directories where the LICENSE should be applied.
  config.copyLicense.directories = ['example/', 'lib/'];

  // Configure whether or not the HTML coverage report should be generated.
  config.coverage.html = false;

  // Configure the port on which examples should be served.
  config.examples.port = 9000;

  // Define the directories to include when running the
  // Dart formatter.
  config.format.directories = ['lib/', 'test/', 'tool/'];

  // Define overrides for local task discovery
  config.local
    ..taskPaths.add('bin')
    ..commandFilePattern = '([a-zA-Z0-9]+)_task.([a-zA-Z0-9]+)'
    ..executables['go'] = ['go', 'run'];

  // Define the location of your test suites.
  config.test
    ..unitTests = ['test/unit/']
    ..integrationTests = ['test/integration/']
    ..functionalTests = ['test/functional'];

  // Execute the dart_dev tooling.
  await dev(args);
}

Full list of configuration options.

Try It Out

The tooling in dart_dev works out of the box with happy defaults for each task. Run ddev or pub run dart_dev to see the help usage. Try it out by running any of the following tasks:

# with the alias
ddev analyze
ddev copy-license
ddev coverage
ddev docs
ddev examples
ddev format
ddev gen-test-runner
ddev saucelabs
ddev test

# without the alias
pub run dart_dev analyze
pub run dart_dev copy-license
pub run dart_dev coverage
pub run dart_dev docs
pub run dart_dev examples
pub run dart_dev format
pub run dart_dev gen-test-runner
pub run dart_dev saucelabs
pub run dart_dev test

Add the -h flag to any of the above commands to receive additional help information specific to that task.

Project Configuration

Project configuration occurs in the tool/dev.dart file where the config instance is imported from the dart_dev package. The bare minimum for this file is:

import 'package:dart_dev/dart_dev.dart';

main(args) async {
  // Available config objects:
  config.analyze
  config.copyLicense
  config.coverage
  config.docs
  config.examples
  config.format
  config.genTestRunner
  config.init
  config.saucelabs
  config.test

  await dev(args);
}

analyze Config

All configuration options for the analyze task are found on the config.analyze object.

Name Type Default Description
entryPoints List<String> ['lib/'] Entry points to analyze. Items in this list can be directories and/or files. Directories will be expanded (depth=1) to find Dart files.
fatalWarnings bool true Treat non-type warnings as fatal.
hints bool true Show hint results.
fatalHints bool false Fail on hints (requests hints to be true).
strong bool false Enable strong static checks

copy-license Config

All configuration options for the copy-license task are found on the config.copyLicense object.

Name Type Default Description
directories List<String> ['lib/'] All source files in these directories will have the LICENSE header applied.
licensePath String 'LICENSE' Path to the source LICENSE file that will be copied to all source files.

coverage config

All configuration options for the coverage task are found on the config.coverage object. However, the coverage task also uses the test suite configuration from the config.test object.

Name Type Default Description
html bool true Whether or not to generate the HTML report.
output String 'coverage/' Output directory for coverage artifacts.
reportOn List<String> ['lib/'] List of paths to include in the generated coverage report (LCOV and HTML).
pubServe bool false Whether or not to serve browser tests using a Pub server.
If true, make sure to follow the test package's setup instructions and include the test/pub_serve transformer.
seleniumCommand String "selenium-server" Command used to execute Selenium for functional testing.
seleniumSuccess String "Selenium Server is up and running" Value used to verify that Selenium has been started successfully. This value is accurate for v2.48.0 of Selenium Server.

Note: "lcov" must be installed in order to generate the HTML report.

If you're using brew, you can install it with: brew update && brew install lcov

Otherwise, visit http://ltp.sourceforge.net/coverage/lcov.php

docs config

There are currently no project-configuration settings for the docs task.

examples Config

All configuration options for the examples task are found on the config.examples object.

Name Type Default Description
hostname String 'localhost' The host name to listen on.
port int 8080 The base port to listen on.

format Config

All configuration options for the format task are found on the config.format object.

Name Type Default Description
check bool false Dry-run; checks if formatter needs to be run and sets exit code accordingly.
directories List<String> ['lib/'] Directories to run the formatter on. All files (any depth) in the given directories will be formatted.

gen-test-runner Config

All configuration options for the gen-test-runner task are found on the config.genTestRunner object.

GenTestRunner
Name Type Default Description
configs List<TestRunnerConfig> [TestRunnerConfig()] The list of runner configurations used to create individual test runners
check bool/code> false If true, will only check to ensure the runner is up-to-date

Note: if you plan to use the --check option, be sure to exclude the generated_runner_test.dart file from formatting. This can be done by adding it to the config.format.exclude list.

Local Config

All configuration options for the local task discovery are found on the config.local object.

Local Discovery
Name Type Default Description
taskPaths List<String> ['tool'] A list of project level paths to search for file matching the task pattern.
followSymlinks bool false Should dart dev expand on symbolic links encountered in any taskPath?
commandFilePattern String '([a-zA-Z0-9]+)_task.([a-zA-Z0-9]+)' A Regular Expression which matches two groups that represent the task name and executable type.
executables Map<String, List<String>> '{'dart': ['dart'], 'sh': ['bash'] }' A lookup table that matches an executable type to a set of strings to prefix the execution of a task file with.
TestRunnerConfig
Name Type Default Description
dartHeaders List<String> [] Any lines of dart code that should exist between test file imports and the main method
preTestCommands List<String> [] Commands to be executed in the generated file's main method before test execution
directory String 'test/' The directory to search for test files in
env Environment Environment.browser The environment to run tests in ('vm' or 'browser')
filename String 'generated_runner' The name of the generated test runner file
genHtml bool false Whether or not a companion html file should be generated
htmlHeaders List<String> [] The list of custom html elements to include in the companion html file

saucelabs Config

All configuration options for the saucelabs task are found on the config.saucelabs object.

Name Type Default Description
filesToTest List<String> [] Html files related to browser tests to be executed on saucelabs (the path will be relative to the test directory)
platforms List<SaucePlatform> [chromeWindows, firefoxWindows, chromeOsx, firefoxOsx, ie10, ie11] Platforms to be executed on saucelabs
pubServePort int 0 Specify the port to run the tests on, otherwise specifying 0 will use a random port
sauceConnectTunnelIdentifier String null The sauce connect tunnel to use, if null then a tunnel will be automatically started
testReportPath String test_reports/sauce_labs_unit_tests.xml Path for test_report
  • In order to use this the following transformer needs to be added to your pubspec.yaml, it must also be applied after the test transformer
- dart_dev/src/sauce_test_harness_transformer:
    $include: [
       "test/**_test{.*,}.dart",
       "test/**_test{.*,}.html",
      ]
  • The html files to be transformed should have the packages/test/dart.js script tag listed last.

  • During this process the test directory will be served which means that the filesToTest must be within the test directory and their path will be relative to the test directory.

test Config

All configuration options for the test task are found on the config.test object.

Name Type Default Description
concurrency int 4 Number of concurrent test suites run.
functionalTests List<String> [] Functional test locations. Items in this list can be directories and/or files.
integrationTests List<String> [] Integration test locations. Items in this list can be directories and/or files.
platforms List<String> [] Platforms on which to run the tests (handled by the Dart test runner). See https://github.com/dart-lang/test#platform-selector-syntax for a full list of supported platforms. * Not all platforms are supported by all continuous integration servers. Please consult your CI server's documentation for more details.
unitTests List<String> ['test/'] Unit test locations. Items in this list can be directories and/or files.
pubServe bool false Whether or not to serve browser tests using a Pub server.
If true, make sure to follow the test package's setup instructions and include the test/pub_serve transformer.
pubServePort int 0 Port used by the Pub server for browser tests. The default value will randomly select an open port to use.
* Individual test files can be executed by appending their path to the end of the command. ``` ddev test path/to/test_name path/to/another/test_name ```
  • Individual tests can be executed by passing in a test name or regex pattern of a test that would be loaded by the test runner
ddev test -n 'run only this test'
  • A new pub serve instance is created for every test run. To use a specific pub serve instance, pass --pub-serve-port to the CLI.
$ pub serve --port 56001 test
$ ddev test --pub-serve --pub-serve-port 56001

CLI Usage

This package comes with a single executable: dart_dev. To run this executable: ddev or pub run dart_dev. This usage will simply display the usage help text along with a list of supported tasks:

$ ddev
Standardized tooling for Dart projects.

Usage: pub run dart_dev [task] [options]

    --[no-]color    Colorize the output.
                    (defaults to on)

-h, --help          Shows this usage.
-q, --quiet         Minimizes the logging output.
    --version       Shows the dart_dev package version.

Supported tasks:

    analyze
    copy-license
    coverage
    docs
    examples
    format
    gen-test-runner
    init
    saucelabs
    test
  • Static analysis: ddev analyze
  • Applying license to source files: ddev copy-license
  • Code coverage: ddev coverage
  • Documentation generation: ddev docs
  • Serving examples: ddev examples
  • Dart formatter: ddev format
  • Generate test runner: ddev gen-test-runner
  • Initialization: ddev init
  • Tests: ddev test

Add the -h flag to any of the above commands to see task-specific flags and options.

Any project configuration defined in the tool/dev.dart file should be reflected in the execution of the above commands. CLI flags and options will override said configuration.

Programmatic Usage

The tooling facilitated by this package can also be executed via a programmatic Dart API:

import 'package:dart_dev/api.dart' as api;

main() async {
  await api.analyze();
  await api.serveExamples();
  await api.format();
  await api.init();
  await api.test();
}

Check out the source of these API methods for additional documentation.

In order to provide a clean API, these methods do not leverage the configuration instances that the command-line interfaces do. Because of this, the default usage may be different. You can access said configurations from the main package:dart_dev/dart_dev.dart import.

Functional Test Code Coverage

If you're running functional tests with Selenium and webdriver.dart, dart_dev can help you run the Selenium standalone server and collect coverage from those functional tests.

As the webdriver.dart project documents, selenium-server-standalone and chromedriver are required dependencies.

selenium-server-standalone

brew install selenium-server-standalone

If you need to use multiple versions of Selenium, you can create a local executable and store it in your project's tool/ directory (and check it in to version control). You can then pass the path to this local executable to the Selenium helper (see configuring dart_dev to run Selenium).

cd tool/
curl -o selenium-server-standalone.jar http://selenium-release.storage.googleapis.com/2.48/selenium-server-standalone-2.48.2.jar
echo '#!/usr/bin/env bash' | tee -a selenium-server
echo 'DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"' | tee -a selenium-server
echo 'exec java -jar $DIR/selenium-server-standalone.jar "$@"' | tee -a selenium-server
chmod +x selenium-server

chromedriver

Normally, chromedriver could be installed with brew, but to collect coverage, the functional tests need to be run in Dartium, which requires an older version of chromedriver (currently 2.14).

Download chromedriver 2.14 here:

https://chromedriver.storage.googleapis.com/index.html?path=2.14/

Unzip and run the executable once to place it in /usr/local/bin/.

Configuring dart_dev to run Selenium

tool/dev.dart

import 'package:dart_dev/dart_dev.dart';
import 'package:dart_dev/util.dart' show SeleniumHelper;

main() async {
  // By default, this helper assumes the `selenium-server` executable is in the path
  var selenium = new SeleniumHelper();

  // If you have a local executable, point to it like so:
  var selenium = new SeleniumHelper(executablePath: 'tool/selenium-server');

  config.test
    ..before = [selenium.start]
    ..after = [selenium.stop];
}

Note: you may also want to spin up a pub instance here to serve the application that will be exercised in your functional tests.

Example functional test

import 'package:test/test.dart';
import 'package:webdriver/io.dart';

WebDriver driver;

void main() {
  setUp(() async {
    var options = {
      'browserName': 'chrome',
      'chromeOptions': {
        'binary': 'path/to/dartium'
      }
    };
    driver = await createDriver(desired: options);
  });

  // Do not quit the webdriver because the test and coverage tasks will handle
  // closing the browser when complete.
  //tearDown(() => driver.quit());

  test('test', () async {
    // This requires that your application is being served at localhost:8080
    await driver.get('http://localhost:8080');
    // interact with application
  });
}

The coverage and test tasks will both handle closing any Dartium instances that were opened via the WebDriver once the tests are complete. You will need to omit the standard tearDown(() => driver.quit()); from your test setups or code coverage cannot be collected.

Libraries

dart_dev
dart_dev.api
dart_dev.util