adfe654733
* Performance improvements Two main changes: 1. Cache parsed AST in a Source. So Parser will parse content only once. 2. Use one unified visitor with multiple callbacks instead of multiple visitors to traverse AST. This improves performance significantly, for example running it on Crystal repository takes ~1 second, which 6 times faster than before. * Change readme example
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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 tool for enforcing a consistent Crystal code style, for catching code smells and wrong code constructions. Ameba's rules traverse AST and report bad parts of your code.
Is still under construction, compatibility may be broken 🚧
Installation
Add this to your application's shard.yml:
development_dependencies:
ameba:
github: veelenga/ameba
That will compile and install ameba binary onto your system.
Or just compile it from sources make install.
Usage
Run ameba binary to catch code issues within you project:
$ ameba
Inspecting 18 files.
...............F.F
18 inspected, 2 failures.
src/ameba/source.cr:26
LineLength: Line too long (82 symbols)
src/ameba.cr:12
UnlessElse: Favour if over unless with else
Write a new Rule
Adding a new rule is as simple as inheriting from Rule struct and implementing
your logic to detect a problem:
struct DebuggerStatement < Rule
# This is a required method to be implemented by the rule.
# Source will be passed here. If rule finds an issue in this source,
# it reports an error:
#
# source.error rule, line_number, message
#
def test(source)
# This line deletegates verification to a particular AST visitor.
AST::Visitor.new self, source
end
# This method is called once the visitor finds a required node.
def test(source, node : Crystal::Call)
# It reports an error, if there is `debugger` method call
# without arguments and a receiver. That's it, somebody forgot
# to remove a debugger statement.
return unless node.name == "debugger" && node.args.empty? && node.obj.nil?
source.error self, node.location.try &.line_number,
"Possible forgotten debugger statement detected"
end
end
Contributors
- veelenga Vitalii Elenhaupt - creator, maintainer