GSoC ’17 Post #1: Community bonding ends

Project abstract

The aim of the project is to ease the process of testing bears in coala by significantly improving the testing API to yield favorable, easy to understand results, add support for at least 8 additional useful linter bears, integrate the MarkdownBear with useful plugins, and enhance documentation to include the newly written Linter bears.

What are Linter Bears ?

Bears in coala

A bear is meant to do some analysis on source code. It can check your code for potential problems, calculate metrics and even provide corrections for your code. A bear contains the actual subroutine that is responsible for checking code for certain specifications.


Linting is the process of checking the source code for Programmatic as well as Stylistic errors. This is most helpful in identifying some common and uncommon mistakes that are made during coding. A Linter is a program that supports linting (verifying code quality). They are available for most languages like JavaScript, CSS, HTML, Python, etc.

Fusion of the two terminologies

Linter Bears are bears that are capable of wrapping third party open source linters, and to be sustainable even allows you to write custom code analysis routines, thus extending the modular functionality of coala. You don’t have to go through the hassle of learning how to use various tools for different programming languages. With over 64 supported languages(and counting), things get much simpler under a single roof.

Linter Bears to be implemented


To catch little mistakes (duplication of rules for instance) and to enforce a code style guide. This is particularly important with Stylus, which is unopinionated when it comes to syntax. Like Stylus itself, this linter opts for flexibility over rigidity.


textlint is an open source text linting utility written in JavaScript for text and Markdown. It is hard to lint natural language texts, but we try to resolve this issue by pluggable approach.


Useful for Validating your .travis.yml file before committing it reduces common build errors such as

  • invalid YAML
  • missing language key
  • unsupported runtime versions of Ruby, PHP, OTP, etc
  • deprecated features or runtime aliases

An unopinionated and configurable linter and style checker for Pug (formerly Jade).


Artistic Style is a source code indenter, formatter, and beautifier for the C, C++, C++/CLI, Objective‑C, C# and Java programming languages. A filter written in C++ that automatically re-indents and re-formats C / C++ / Objective‑C / C++/CLI / C# / Java source files. It can be used from a command line, or it can be incorporated as a library in another program.


Reek is a tool that examines Ruby classes, modules and methods and reports any Code Smells it finds. Reek focuses on high-level code smells, so we can’t tell you how to fix warnings in a generic fashion; this is and will always be completely dependent on your domain language and business logic.


CSScomb is a coding style formatter for CSS. You can easily write your own configuration to make your style sheets beautiful and consistent.


HTTPolice is a lint for HTTP requests and responses. It checks them for conformance to standards and best practices. As a command-line tool, it can read HAR files or raw HTTP/1.x TCP streams.


The community bonding has come to an end and I’ve nearly managed to complete my milestone. It has been a wonderful time so far. I’ve manually installed and tested all the linters that I’m going to integrate and went through their configurations. I’ve also designed the modified testing API yielding useful results which will be described in the upcoming blog. Till then, let the coding begin !