Remove sqlite3 lines from .gitignore if the application is not using sqlite3.

railties/CHANGELOG.md

+*   Remove sqlite3 lines from `.gitignore` if the application is not using sqlite3.
+
+    *Dmitrii Golub*
+
 *   Add public API to register new extensions for `rake notes`.
 
     Example:

railties/lib/rails/generators/app_base.rb

@@ -172,6 +172,10 @@ def comment_if(value)
         options[value] ? '# ' : ''
       end
 
+      def sqlite3?
+        !options[:skip_active_record] && options[:database] == 'sqlite3'
+      end
+
       class GemfileEntry < Struct.new(:name, :version, :comment, :options, :commented_out)
         def initialize(name, version, comment, options = {}, commented_out = false)
           super

railties/lib/rails/generators/rails/app/app_generator.rb

@@ -50,7 +50,7 @@ def configru
     end
 
     def gitignore
-      copy_file "gitignore", ".gitignore"
+      template "gitignore", ".gitignore"
     end
 
     def app

railties/lib/rails/generators/rails/app/templates/gitignore

@@ -7,10 +7,12 @@
 # Ignore bundler config.
 /.bundle
 
+<% if sqlite3? -%>
 # Ignore the default SQLite database.
 /db/*.sqlite3
 /db/*.sqlite3-journal
 
+<% end -%>
 # Ignore all logfiles and tempfiles.
 /log/*.log
 /tmp

railties/test/generators/app_generator_test.rb

@@ -408,7 +408,31 @@ def test_skip_spring
     end
   end
 
-protected
+  def test_gitignore_when_sqlite3
+    run_generator
+
+    assert_file '.gitignore' do |content|
+      assert_match(/sqlite3/, content)
+    end
+  end
+
+  def test_gitignore_when_no_active_record
+    run_generator [destination_root, '--skip-active-record']
+
+    assert_file '.gitignore' do |content|
+      assert_no_match(/sqlite3/, content)
+    end
+  end
+
+  def test_gitignore_when_non_sqlite3_db
+    run_generator([destination_root, "-d", "mysql"])
+
+    assert_file '.gitignore' do |content|
+      assert_no_match(/sqlite3/, content)
+    end
+  end
+
+  protected
 
   def action(*args, &block)
     silence(:stdout) { generator.send(*args, &block) }