Added constant validation (#1)

* Added constant validation

* Update CHANGELOG.md

Author: programyan

CHANGELOG.md

@@ -2,7 +2,9 @@
 
 ## main (unreleased)
 
----
+### New Features
+
+- [#1](https://github.com/programyan/strong_interface/pull/1) Added constants validation
 
 ## 0.2.0
 

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    strong_interface (0.1.0)
+    strong_interface (0.2.0)
 
 GEM
   remote: https://rubygems.org/

README.md

@@ -32,6 +32,7 @@ Or install it yourself as:
 
 ```ruby
 module IDog
+  WORD = String
   def self.create(*); end
   def eat(food); end
   def voice; end
@@ -45,6 +46,8 @@ class Lessy
   extend StrongInterface
   implements IDog
 
+  WORD = 'gav'
+
   def self.create(name)
     # Creating...
   end
@@ -54,7 +57,7 @@ class Lessy
   end
 
   def voice
-    'Gav'
+    WORD
   end
 end
 ```
@@ -79,7 +82,8 @@ end
 #### Exception will be raised
 
 ```shell
-StrongInterface::MethodNotImplemented (Class method `create` is not implemented at `Lessy`)
+StrongInterface::ImplementationError (Constant `WORD` is absent at `Lessy`)
+Class method `create` is not implemented at `Lessy`
 Invalid parameters at method `eat`, expected: `def eat(food)`, got: `def eat(food, water)`
 ```
 
@@ -92,7 +96,7 @@ If the variable is not set, the `raise` strategy will be applied.
 
 #### raise (default)
 
-This is a default strategy. When validator finds incorrect implementation, it raises the `StrongInterface::MethodNotImplemented` exception,
+This is a default strategy. When validator finds incorrect implementation, it raises the `StrongInterface::ImplementationError` exception,
 and provides a list of methods which aren't implemented
 
 #### log
@@ -105,6 +109,8 @@ even if it has this kind of a problem in code.
 
 - [x] Check if methods of interfaces all exists in a class or module
 - [x] Check the arguments of methods
+- [x] Check constants
+- [ ] Checking the privacy of methods
 - [ ] Allow optional arguments at interface methods???
 
 ## Development

lib/strong_interface.rb

@@ -4,17 +4,18 @@
 require 'strong_interface/parameters_validator'
 
 module StrongInterface
-  MethodNotImplemented = Class.new(StandardError)
+  ImplementationError = Class.new(StandardError)
   UnknownStrategy = Class.new(StandardError)
 
   RAISING_STRATEGIES = {
-    'raise' => ->(error) { raise MethodNotImplemented, error },
+    'raise' => ->(error) { raise ImplementationError, error },
     'log' => ->(error) { Logger.new($stdout).warn { error } }
   }.freeze
 
   # @param interfaces [Module|Class|Array<Module|Class>] the list of interfaces that class or module should implements
-  # @raise [UnknownStrategy] if SI_NOTIFICATION environment variable has wrong value
-  # @raise [ImplementationError] if describing some methods of an interface has been forgotten and SI_NOTIFICATION environment variable is set to `raise`
+  # @raise [UnknownStrategy] if SI_VALIDATION_STRATEGY environment variable has wrong value
+  # @raise [ImplementationError] if describing some methods of an interface has been forgotten and
+  #                              SI_VALIDATION_STRATEGY environment variable is set to `raise`
   def implements(interfaces)
     TracePoint.trace(:end) do |t|
       next if self != t.self
@@ -34,13 +35,19 @@ def implements(interfaces)
 
   def validate(interfaces)
     Array(interfaces).flat_map do |interface|
-      validate_class_methods(interface) + validate_instance_methods(interface)
+      validate_constants(interface) + validate_class_methods(interface) + validate_instance_methods(interface)
+    end
+  end
+
+  def validate_constants(interface)
+    (interface.constants - constants).map do |missing_constant|
+      "Constant `#{missing_constant}` is absent at `#{self}`"
     end
   end
 
   def validate_class_methods(interface)
     interface.methods(false).filter_map do |klass_method|
-      unless methods(false).include?(klass_method)
+      if !methods(false).include?(klass_method)
         "Class method `#{klass_method}` is not implemented at `#{self}`"
       else
         ParametersValidator.new(interface.method(klass_method), method(klass_method)).validate
@@ -50,7 +57,7 @@ def validate_class_methods(interface)
 
   def validate_instance_methods(interface)
     interface.instance_methods.filter_map do |instance_method|
-      unless instance_methods.include?(instance_method)
+      if !instance_methods.include?(instance_method)
         "Instance method `#{instance_method}` is not implemented at `#{self}`"
       else
         ParametersValidator.new(interface.instance_method(instance_method), instance_method(instance_method)).validate

lib/strong_interface/parameters_validator.rb

@@ -24,16 +24,17 @@ def valid?
       return false if @interface_method_parameters.size != @klass_method_parameters.size
 
       @interface_method_parameters.each.with_index.all? do |key, index|
-        if key == :req
-          %i(req opt).include? @klass_method_parameters[index]
-        elsif key == :keyreq
-          %i(keyreq key).include? @klass_method_parameters[index]
+        case key
+        when :req
+          %i[req opt].include? @klass_method_parameters[index]
+        when :keyreq
+          %i[keyreq key].include? @klass_method_parameters[index]
         end
       end
     end
 
-    def description(m)
-      m.inspect.scan(/[\.|#](\S+?\(.*?\))/).last.first
+    def description(metod)
+      metod.inspect.scan(/[.|#](\S+?\(.*?\))/).last.first
     end
   end
-end
+end

spec/strong_interface_spec.rb

@@ -20,7 +20,28 @@ def say(text)
           # Say text somehow
         end
       end
-    }.to raise_error(StrongInterface::MethodNotImplemented)
+    }.to raise_error(StrongInterface::ImplementationError)
+  end
+
+  context 'with missing constant' do
+    it 'raises error' do
+      expect {
+        module IScream
+          LOUD = Integer
+
+          def scream; end
+        end
+
+        class TestClass
+          extend StrongInterface
+          implements IScream
+
+          def scream
+            # Scream something somehow
+          end
+        end
+      }.to raise_error(StrongInterface::ImplementationError)
+    end
   end
 
   it 'do not raise error when everything is ok' do