CredoContrib

CredoContrib is a set of additional checks for the Credo static analysis tool.
Many of the checks are implementations of rules from
christopheradams/elixir_style_guide. Contributions welcome!

Installation

Add credo_contrib to the list of dependencies in your mix.exs:

def deps do
  [
    {:credo_contrib, "~> 0.2.0", only: [:dev, :test], runtime: false}
  ]
end

Usage

Add CredoContrib as a plugin in your .credo.exs to enable all checks:

%{
  configs: [
    %{
      name: "default",
      plugins: [
        {CredoContrib, []}
      ]
    }
  ]
}

Or add the desired checks individually:

%{
  configs: [
    %{
      name: "default",
      checks: [
        {CredoContrib.Check.FunctionBlockSyntax, allow_single_kw_defs: false},
        # …
      ]
    }
  ]
}

Available Checks

CredoContrib.Check.DocWhitespace

Disallows extranneous whitespace in documentation strings:

## GOOD
defmodule Foo do
  @moduledoc """
  This is a module
  """
  @doc """
  This is a function
  """
  def bar do
    :ok
  end
end
## BAD
defmodule Foo do
  @moduledoc """
  This is a module
  """
  @doc """
  This is a function
  """
  def bar do
    :ok
  end
end

CredoContrib.Check.EmptyDocString

Disallows @doc strings that do not contain any text.

## GOOD
@doc """
This is a function
"""
def bar do
  :ok
end
## BAD
@doc """
"""
def bar do
  :ok
end

CredoContrib.Check.EmptyTestBlock

Disallows usage of ExUnit.Case.test/3 with an empty body.

For unimplemented tests, use ExUnit.Case.test/1 and set ExUnit.start(except: [:not_implemented])

## GOOD
test "something not implemented"
test "something implemented" do
  assert 1 + 1 == 2
end
## BAD
test "something not implemented" do
end

CredoContrib.Check.FunctionBlockSyntax

Disallows mixing of def …, do: syntax with multiple def … do … end-style
definitions

https://github.com/christopheradams/elixir_style_guide#multiple-function-defs

Options

• allow_single_kw_defs (default: true): Set to false to only allow def …, do: syntax for
  functions with multiple heads

CredoContrib.Check.FunctionNameUnderscorePrefix

Disallows function names prefixed with a single underscore

https://github.com/christopheradams/elixir_style_guide#private-functions-with-same-name-as-public

CredoContrib.Check.ModuleAlias

Disallows alias __MODULE__ and @foo __MODULE__

https://github.com/christopheradams/elixir_style_guide#module-pseudo-variable

CredoContrib.Check.ModuleDirectivesOrder

Enforces consistent ordering for module attributes and directives.

https://github.com/christopheradams/elixir_style_guide#module-attribute-ordering

CredoContrib.Check.PublicPrivateFunctionName

Disallows public and private functions with the same name

https://github.com/christopheradams/elixir_style_guide#private-functions-with-same-name-as-public

CredoContrib.Check.SingleFunctionPipe

Disallows usage of the pipe operator with a single function call

https://github.com/christopheradams/elixir_style_guide#avoid-single-pipelines

Options

• ignored_locals: Keyword list of names and arities of local functions to ignore. E.g., [expect: 3, stub: 3]

Development

Setup

bin/setup

Running the tests

bin/test

License

ISC