Ameba
Code style linter for Crystal
(a single-celled animal that catches food and moves about by extending fingerlike projections of protoplasm)
## About
Ameba is a static code analysis tool for the Crystal language.
It enforces a consistent [Crystal code style](https://crystal-lang.org/docs/conventions/coding_style.html),
also catches code smells and wrong code constructions.
See also [Roadmap](https://github.com/veelenga/ameba/wiki).
## Usage
Run `ameba` binary within your project directory to catch code issues:
```sh
$ ameba
Inspecting 107 files.
...............F.....................F....................................................................
src/ameba/rule/unneeded_disable_directive.cr:29:7
Lint/UselessAssign: Useless assignment to variable `s`
src/ameba/formatter/flycheck_formatter.cr:5:21
Lint/UnusedArgument: Unused argument `location`
Finished in 248.9 milliseconds
107 inspected, 2 failures.
```
## Installation
### As a project dependency:
Add this to your application's `shard.yml`:
```yaml
development_dependencies:
ameba:
github: veelenga/ameba
version: 0.8.1
```
Build `bin/ameba` binary within your project directory while running `shards install`.
You may also want to use it on [Travis](travis-ci.org):
```yaml
# .travis.yml
language: crystal
install:
- shards install
script:
- crystal spec
- bin/ameba
```
Using this config Ameba will inspect files just after the specs run. Travis will also fail
the build if some problems detected.
### OS X
```sh
$ brew tap veelenga/tap
$ brew install ameba
```
### Docker
Build the image:
```sh
$ docker build -t ameba/ameba .
```
To use the resulting image on a local source folder, mount the current (or target) directory into `/src`:
```sh
$ docker run -v $(pwd):/src ameba/ameba
```
### From sources
```sh
$ git clone https://github.com/veelenga/ameba && cd ameba
$ make install
```
## Configuration
Default configuration file is `.ameba.yml`.
It allows to configure rule properties, disable specific rules and exclude sources from the rules.
Generate new file by running `ameba --gen-config`.
### Only/Except
One or more rules, or a one or more group of rules can be included or excluded
via command line arguments:
```
$ ameba --only Lint/Syntax # runs only Lint/Syntax rule
$ ameba --only Style,Lint # runs only rules from Style and Lint groups
$ ameba --except Lint/Syntax # runs all rules except Lint/Syntax
$ ameba --except Style,Lint # runs all rules except rules in Style and Lint groups
```
### Inline disabling
One or more rules or one or more group of rules can be disabled using inline directives:
```crystal
# ameba:disable Style/LargeNumbers
time = Time.epoch(1483859302)
time = Time.epoch(1483859302) # ameba:disable Style/LargeNumbers, Lint/UselessAssign
time = Time.epoch(1483859302) # ameba:disable Style, Lint
```
## Editor integration
* Vim: [vim-crystal](https://github.com/rhysd/vim-crystal) (via [Syntastic](https://github.com/vim-syntastic/syntastic))
* Emacs: [ameba.el](https://github.com/veelenga/ameba.el)
* Sublime Text: [Sublime Linter Ameba](https://github.com/epergo/SublimeLinter-contrib-ameba)
## Credits & inspirations
- [Crystal Language](crystal-lang.org)
- [Rubocop](http://rubocop.readthedocs.io/en/latest/)
- [Credo](http://credo-ci.org/)
- [Dogma](https://github.com/lpil/dogma)
## Contributors
- [veelenga](https://github.com/veelenga) Vitalii Elenhaupt - creator, maintainer