Overview

This is the style guide for Autonomy for all Dart code, based off:

Effective Dart https://dart.dev/effective-dart

If you are uncertain, refer to Effective Dart documentation or asks the Autonomy leads for help.

Dart Linter

TODO: research the Dart Linter lints | Dart package

Files

Name packages, directories, and source files using snake_case:

my_package
└─ lib
   └─ file_system.dart
   └─ slider_menu.dart

File contents end with 1 blank line:

Amazing dart code...
// Last blank line below, then end of file

Indentation

Idents are 2 spaces long Why two spaces instead of four?. If you are using Visual Studio Code this will be the default with the Dart extension installed
Blank lines do not have spaces
Strings are encoded with UTF-8 and enclosed with single quotes to maintain consistency with the Flutter style guide https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo#prefer-single-quotes-for-strings

Imports

One space between each import level
Sort each import section alphabetically

Import order:

System-level imports: Anything that starts with import 'dart:__'
Installed packages: Anything that starts with import 'package:__'
Local packages: Anything written by/for WARG (including submodules)

Name import prefixes using snake_case:

import 'dart:math' as math;

import 'package:angular_components/angular_components.dart' as angular_components;
import 'package:js/js.dart' as js;

import 'util.dart';

Identifier naming

variableNames in lowerCamelCase
constantNames in lowerCamelCase
functionNames in lowerCamelCase
Classes, enumerated types, typedefs and type parameters should be in UpperCamelCase

Variables

use final for local variables that are not re-assigned

Classes

Private members (methods and attributes) are prefixed with 1 underscore

Initialize fields at their declaration when possible

Logic

Use curly braces for all flow control statements
- Exception: if statement with no else clause and whole if statement fits on one line, can omit braces
Put subsequent if and else on the same line as previous block’s closing brace

Avoid using true or false in equality operations

Functions

Use = to separate parameters from its default value

Operators

No spaces around : if it's used as a slicing operator, otherwise space after:
One space on either side of all binary operators, including assignment operators
- Ex: + - * / % , += -= *= /=, > < == !=
One space after every comma

Strings

Use adjacent strings to concatenate string literals
Use interpolation to combine string and values
- Avoid curly braces when not necessary

Misc

Lines are 100 characters long
No spaces at the end of a line

Multiline

Commenting

Format comments like sentences

Doc comments TODO: investigate dart doc

use /// to document members and types
Dart doc can find & generate comments for it
Start doc comments with single-sentence summary
Separate first sentence from rest of description

General Example

No commented out and unreachable code

Do not add code that you have commented out. It is better to just delete it. Git and GitHub will keep a record if it’s ever needed again.

Additionally, delete unreachable code (code that will never be run). For example:

Dart Style Guide (WIP)