Phantom migrations status rake task (#35)

* phantom migrations rake task

* refactor

* refactor

* fix loading commands

* fix tests

* add tests

lib/actual_db_schema.rb

@@ -6,6 +6,10 @@
 require_relative "actual_db_schema/patches/migrator"
 require_relative "actual_db_schema/patches/migration_context"
 
+require_relative "actual_db_schema/commands/base"
+require_relative "actual_db_schema/commands/rollback"
+require_relative "actual_db_schema/commands/list"
+
 # The main module definition
 module ActualDbSchema
   raise NotImplementedError, "ActualDbSchema is only supported in Rails" unless defined?(Rails)

lib/actual_db_schema/commands/base.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+module ActualDbSchema
+  module Commands
+    # Base class for all commands
+    class Base
+      def call
+        unless ActualDbSchema.config.fetch(:enabled, true)
+          raise "ActualDbSchema is disabled. Set ActualDbSchema.config[:enabled] = true to enable it."
+        end
+
+        if ActiveRecord::Migration.current_version >= 6
+          ActiveRecord::Tasks::DatabaseTasks.raise_for_multi_db(command: "db:rollback_branches")
+        end
+
+        call_impl
+      end
+
+      private
+
+      def call_impl
+        raise NotImplementedError
+      end
+
+      def context
+        @context ||=
+          ActiveRecord::Base.connection.migration_context.tap do |c|
+            c.extend(ActualDbSchema::Patches::MigrationContext)
+          end
+      end
+    end
+  end
+end

lib/actual_db_schema/commands/list.rb

@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+module ActualDbSchema
+  module Commands
+    # Shows the list of phantom migrations
+    class List < Base
+      private
+
+      def call_impl
+        preambule
+        table
+      end
+
+      def indexed_phantom_migrations
+        @indexed_phantom_migrations ||= context.migrations.index_by { |m| m.version.to_s }
+      end
+
+      def preambule
+        puts "\nPhantom migrations\n\n"
+        puts "Below is a list of irrelevant migrations executed in unmerged branches."
+        puts "To bring your database schema up to date, the migrations marked as \"up\" should be rolled back."
+        puts "\ndatabase: #{ActiveRecord::Base.connection_db_config.database}\n\n"
+        puts %(#{"Status".center(8)}  #{"Migration ID".ljust(14)}  Migration File)
+        puts "-" * 50
+      end
+
+      def table
+        context.migrations_status.each do |status, version|
+          migration = indexed_phantom_migrations[version]
+          next unless migration
+
+          puts %(#{status.center(8)}  #{version.to_s.ljust(14)}  #{migration.filename.gsub("#{Rails.root}/", "")})
+        end
+      end
+    end
+  end
+end

lib/actual_db_schema/commands/rollback.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module ActualDbSchema
+  module Commands
+    # Rolls back all phantom migrations
+    class Rollback < Base
+      private
+
+      def call_impl
+        context.rollback_branches
+
+        return if ActualDbSchema.failed.empty?
+
+        puts ""
+        puts "[ActualDbSchema] Irreversible migrations were found from other branches. Roll them back or fix manually:"
+        puts ""
+        puts ActualDbSchema.failed.map { |migration| "- #{migration.filename}" }.join("\n")
+        puts ""
+      end
+    end
+  end
+end

lib/tasks/db.rake

@@ -3,24 +3,12 @@
 namespace :db do
   desc "Rollback migrations that were run inside not a merged branch."
   task rollback_branches: :load_config do
-    unless ActualDbSchema.config.fetch(:enabled, true)
-      raise "ActualDbSchema is disabled. Set ActualDbSchema.config[:enabled] = true to enable it."
-    end
-
-    if ActiveRecord::Migration.current_version >= 6
-      ActiveRecord::Tasks::DatabaseTasks.raise_for_multi_db(command: "db:rollback_branches")
-    end
+    ActualDbSchema::Commands::Rollback.new.call
+  end
 
-    context = ActiveRecord::Base.connection.migration_context
-    context.extend(ActualDbSchema::Patches::MigrationContext)
-    context.rollback_branches
-    if ActualDbSchema.failed.any?
-      puts ""
-      puts "[ActualDbSchema] Irreversible migrations were found from other branches. Roll them back or fix manually:"
-      puts ""
-      puts ActualDbSchema.failed.map { |migration| "- #{migration.filename}" }.join("\n")
-      puts ""
-    end
+  desc "List all phantom migrations - non-relevant migrations that were run inside not a merged branch."
+  task phantom_migrations: :load_config do
+    ActualDbSchema::Commands::List.new.call
   end
 
   task _dump: :rollback_branches

test/dummy_app/db/schema.rb

@@ -10,5 +10,5 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[6.0].define(version: 0) do
+ActiveRecord::Schema[7.1].define(version: 0) do
 end

test/rake_task_test.rb

@@ -2,19 +2,6 @@
 
 require "test_helper"
 
-class TestingState
-  class << self
-    attr_accessor :up, :down
-  end
-
-  def self.reset
-    self.up = []
-    self.down = []
-  end
-
-  reset
-end
-
 def app_file(path)
   Rails.application.config.root.join(path)
 end
@@ -77,24 +64,26 @@ def prepare_phantom_migrations
   delete_migrations_files # simulate switching branches
 end
 
-describe "db:rollback_branches" do
-  let(:migrated_files) do
-    Dir.glob(app_file("tmp/migrated/*.rb")).map { |f| File.basename(f) }.sort
+def cleanup
+  delete_migrations_files
+  if ActiveRecord::SchemaMigration.respond_to?(:create_table)
+    ActiveRecord::SchemaMigration.create_table
+  else
+    ActiveRecord::SchemaMigration.new(ActiveRecord::Base.connection).create_table
   end
+  run_sql("delete from schema_migrations")
+  remove_app_dir("tmp/migrated")
+  define_migrations
+  Rails.application.load_tasks
+  TestingState.reset
+end
 
-  before do
-    delete_migrations_files
-    if ActiveRecord::SchemaMigration.respond_to?(:create_table)
-      ActiveRecord::SchemaMigration.create_table
-    else
-      ActiveRecord::SchemaMigration.new(ActiveRecord::Base.connection).create_table
-    end
-    run_sql("delete from schema_migrations")
-    remove_app_dir("tmp/migrated")
-    define_migrations
-    Rails.application.load_tasks
-    TestingState.reset
-  end
+def migrated_files
+  Dir.glob(app_file("tmp/migrated/*.rb")).map { |f| File.basename(f) }.sort
+end
+
+describe "db:rollback_branches" do
+  before { cleanup }
 
   it "creates the tmp/migrated folder" do
     refute File.exist?(app_file("tmp/migrated"))
@@ -144,3 +133,21 @@ def down
     end
   end
 end
+
+describe "db:phantom_migrations" do
+  before { cleanup }
+
+  def run_task
+    Rake::Task["db:phantom_migrations"].invoke
+    Rake::Task["db:phantom_migrations"].reenable
+  end
+
+  it "shows the list of phantom migrations" do
+    prepare_phantom_migrations
+    run_task
+    assert_match(/ Status   Migration ID    Migration File/, TestingState.output)
+    assert_match(/--------------------------------------------------/, TestingState.output)
+    assert_match(%r{   up     20130906111511  tmp/migrated/20130906111511_first.rb}, TestingState.output)
+    assert_match(%r{   up     20130906111512  tmp/migrated/20130906111512_second.rb}, TestingState.output)
+  end
+end

test/test_helper.rb

@@ -25,3 +25,26 @@ def initialize
 ActiveRecord::Base.establish_connection(**db_config)
 
 ActualDbSchema.config[:enabled] = true
+
+class TestingState
+  class << self
+    attr_accessor :up, :down, :output
+  end
+
+  def self.reset
+    self.up = []
+    self.down = []
+    self.output = +""
+  end
+
+  reset
+end
+
+module Kernel
+  alias original_puts puts
+
+  def puts(*args)
+    TestingState.output << args.join("\n")
+    original_puts(*args)
+  end
+end