Module: Reek::Spec

Defined in:
lib/reek/spec.rb,
lib/reek/spec/should_reek.rb,
lib/reek/spec/should_reek_of.rb,
lib/reek/spec/should_reek_only_of.rb

Overview

Provides matchers for Rspec, making it easy to check code quality.

If you require this module somewhere within your spec (or in your spec_helper), Reek will arrange to update Spec::Runner’s config so that it knows about the matchers defined here.

Examples

Here’s a spec that ensures there are no active code smells in the current project:

describe 'source code quality' do
  Dir['lib/**/*.rb'].each do |path|
    it "reports no smells in #{path}" do
      File.new(path).should_not reek
    end
  end
end

And here’s an even simpler way to do the same:

it 'has no code smells' do
  Dir['lib/**/*.rb'].should_not reek
end

Here’s a simple check of a code fragment:

'def equals(other) other.thing == self.thing end'.should_not reek

To check for specific smells, use something like this:

ruby = 'def double_thing() @other.thing.foo + @other.thing.foo end'
ruby.should reek_of(:Duplication, /@other.thing[^\.]/)
ruby.should reek_of(:Duplication, /@other.thing.foo/)
ruby.should_not reek_of(:FeatureEnvy)

Defined Under Namespace

Classes: ShouldReek, ShouldReekOf, ShouldReekOnlyOf

Instance Method Summary collapse

Instance Method Details

#reek ⇒ Object

Returns true if and only if the target source code contains smells.



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# File 'lib/reek/spec.rb', line 106

def reek
  ShouldReek.new
end

#reek_of(smell_category, smell_details = {}) ⇒ Object

Checks the target source code for instances of “smell category” and returns true only if it can find one of them that matches.

Remember that this includes our “smell types” as well. So it could be the “smell type” UtilityFunction, which is represented as a concrete class in reek but it could also be “Duplication” which is a “smell categgory”.

In theory you could pass many different types of input here:

- :UtilityFunction
- "UtilityFunction"
- UtilityFunction (this works in our specs because we tend to do "include Reek:Smells")
- Reek::Smells::UtilityFunction (the right way if you really want to pass a class)
- "Duplication" or :Duplication which is an abstract "smell category"

It is recommended to pass this as a symbol like :UtilityFunction. However we don’t enforce this.

Additionally you can be more specific and pass in “smell_details” you want to check for as well e.g. “name” or “count” (see the examples below). The parameters you can check for are depending on the smell you are checking for. For instance “count” doesn’t make sense everywhere whereas “name” does in most cases. If you pass in a parameter that doesn’t exist (e.g. you make a typo like “namme”) reek will raise an ArgumentError to give you a hint that you passed something that doesn’t make much sense.

smell_category - The “smell category” or “smell_type” we check for. smells_details - A hash containing “smell warning” parameters

Examples

Without smell_details:

reek_of(:FeatureEnvy)
reek_of(Reek::Smells::UtilityFunction)

With smell_details:

reek_of(UncommunicativeParameterName, name: 'x2')
reek_of(DataClump, count: 3)

Examples from a real spec

expect(src).to reek_of(Reek::Smells::DuplicateMethodCall, name: '@other.thing')



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# File 'lib/reek/spec.rb', line 88

def reek_of(smell_category, smell_details = {})
  ShouldReekOf.new(smell_category, smell_details)
end

#reek_only_of(smell_category) ⇒ Object

See the documentaton for “reek_of”.

Notable differences to reek_of:

1.) "reek_of" doesn't mind if there are other smells of a different category.
    "reek_only_of" will fail in that case.
2.) "reek_only_of" doesn't support the additional smell_details hash.



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# File 'lib/reek/spec.rb', line 99

def reek_only_of(smell_category)
  ShouldReekOnlyOf.new(smell_category)
end