Fix block context (#11)

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    filterable-by (0.6.2)
+    filterable-by (0.6.3)
       activerecord
       activesupport
 

filterable-by.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name        = 'filterable-by'
-  s.version     = '0.6.2'
+  s.version     = '0.6.3'
   s.authors     = ['Dimitrij Denissenko']
   s.email       = ['dimitrij@blacksquaremedia.com']
   s.summary     = 'Generate white-listed filter scopes from URL parameter values'

lib/filterable_by.rb

@@ -4,40 +4,56 @@
 
 module ActiveRecord
   module FilterableBy
-    def self.normalize(value)
-      case value
-      when String, Numeric
-        value
-      when Array
-        value.select {|v| normalize(v) }
+    class << self
+      def normalize(value)
+        case value
+        when String, Numeric
+          value
+        when Array
+          value.select {|v| normalize(v) }
+        end
       end
-    end
 
-    def self.merge(scope, unscoped, hash, name, **opts, &block)
-      key = name
-      positive = normalize(hash[key]) if hash.key?(key)
-      if positive.present?
-        sub = block.arity == 2 ? yield(unscoped, positive, **opts) : yield(positive, **opts)
-        return nil unless sub
+      def merge(scope, unscoped, hash, name, **opts, &block)
+        key = name
+        positive = normalize(hash[key]) if hash.key?(key)
+        if positive.present?
+          sub = eval_scope(scope, unscoped, positive, **opts, &block)
+          return nil unless sub
+
+          scope = scope.merge(sub)
+        end
+
+        key = "#{name}_not"
+        negative = normalize(hash[key]) if hash.key?(key)
+        if negative.present?
+          sub = eval_scope(scope, unscoped, negative, **opts, &block)
+          return nil unless sub
 
-        scope = scope.merge(sub)
+          scope = scope.merge(invert_where(sub))
+        end
+
+        scope
       end
 
-      key = "#{name}_not"
-      negative = normalize(hash[key]) if hash.key?(key)
-      if negative.present?
-        sub = block.arity == 2 ? yield(unscoped, negative, **opts) : yield(negative, **opts)
-        return nil unless sub
+      private
 
-        if sub.respond_to?(:invert_where)
-          sub = sub.invert_where
+      def eval_scope(scope, unscoped, value, **opts, &block)
+        if block.arity == 2
+          scope.instance_exec(unscoped, value, **opts, &block)
         else
-          sub.where_clause = sub.where_clause.invert
+          scope.instance_exec(value, **opts, &block)
         end
-        scope = scope.merge(sub)
       end
 
-      scope
+      def invert_where(scope)
+        if scope.respond_to?(:invert_where!)
+          scope.invert_where!
+        else
+          scope.where_clause = scope.where_clause.invert
+        end
+        scope
+      end
     end
 
     module ClassMethods
@@ -58,7 +74,7 @@ def filterable_by(*names, &block)
         end
 
         names.each do |name|
-          _filterable_by_config[name.to_s] = block
+          _filterable_by_config[name.to_s] = block || ->(value, **) { where(name.to_sym => value) }
         end
       end
 
@@ -74,7 +90,6 @@ def filter_by(hash = nil, **opts)
         return scope unless hash.respond_to?(:key?) && hash.respond_to?(:[])
 
         _filterable_by_config.each do |name, block|
-          block = ->(value, **) { where(name.to_sym => value) } if block.nil?
           scope = FilterableBy.merge(scope, unscoped, hash, name, **opts, &block)
           break unless scope
         end

spec/spec_helper.rb

@@ -27,12 +27,8 @@ class Author < ActiveRecord::Base
 
 class AbstractPost < ActiveRecord::Base
   self.abstract_class = true
-  filterable_by :author_id
-end
-
-class Post < AbstractPost
-  belongs_to :author
 
+  filterable_by :author_id
   filterable_by :only do |value, **opts|
     case value
     when 'me'
@@ -43,6 +39,10 @@ class Post < AbstractPost
   end
 end
 
+class Post < AbstractPost
+  belongs_to :author
+end
+
 class Feedback < ActiveRecord::Base
   belongs_to :author
   belongs_to :post