Add supported Ruby versions - close #39

The specs were failing on newer versions of Ruby due to ActiveRecord 6. There was a hardcoded check for version 5, and this was causing a conditional spec to fallback to version 4. The spec has been updated to now test accordingly when the version is either below or above 5 (this is where the actual distinction lies).

.travis.yml

@@ -7,3 +7,6 @@ script:
 rvm:
   - 2.3
   - 2.4
+  - 2.5
+  - 2.6
+  - 2.7

spec/spec_helper.rb

@@ -9,10 +9,3 @@
 
 load File.dirname(__FILE__) + '/schema.rb'
 require File.dirname(__FILE__) + '/models.rb'
-
-rails5 = `bundle show activerecord`.strip.split('/').last =~ /activerecord-5\./
-exclude_rails = rails5 ? 4 : 5 # don't run tests for the version of rails we are NOT using
-
-RSpec.configure do |config|
-  config.filter_run_excluding rails: exclude_rails
-end

spec/sql_footprint_spec.rb

@@ -28,24 +28,19 @@
       )
     end
 
-    it 'formats selects', rails: 4 do
+    it 'formats selects' do
       Widget.where(name: SecureRandom.uuid, quantity: 1).last
-      expect(statements.to_a).to include(
-        'SELECT  "widgets".* FROM "widgets" ' \
-        'WHERE "widgets"."name" = ? AND ' \
-        '"widgets"."quantity" = ?  ' \
-        'ORDER BY "widgets"."id" DESC LIMIT 1'
-      )
-    end
 
-    it 'formats selects', rails: 5 do
-      Widget.where(name: SecureRandom.uuid, quantity: 1).last
-      expect(statements.to_a).to include(
-        'SELECT  "widgets".* FROM "widgets" ' \
-        'WHERE "widgets"."name" = ? AND ' \
-        '"widgets"."quantity" = ? ' \
-        'ORDER BY "widgets"."id" DESC LIMIT ?'
-      )
+      clean_statements = statements.to_a.map(&:squish)
+
+      sql = <<-SQL.squish
+        SELECT "widgets".* FROM "widgets"
+        WHERE "widgets"."name" = ? AND
+        "widgets"."quantity" = ?
+        ORDER BY "widgets"."id" DESC LIMIT #{ActiveRecord::VERSION::MAJOR < 5 ? '1' : '?'}
+      SQL
+
+      expect(clean_statements).to include(sql)
     end
 
     it 'dedupes the same sql' do

sql_footprint.gemspec

@@ -27,7 +27,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'activerecord', ['>= 3.0']
   spec.add_dependency 'activesupport', ['>= 3.0']
 
-  spec.add_development_dependency 'bundler', '~> 1.7'
+  spec.add_development_dependency 'bundler', ['>= 1.7', '< 3.0']
   spec.add_development_dependency 'rake', '~> 10.0'
   spec.add_development_dependency 'rspec'
   spec.add_development_dependency 'pry'