Class: Synvert::Core::Rewriter

Inherits:
Object
  • Object
show all
Defined in:
lib/synvert/core/rewriter.rb

Overview

Rewriter is the top level namespace in a snippet.

One Rewriter checks if the depndency version matches, and it can contain one or many Instance, which define the behavior what files and what codes to detect and rewrite to what code.

Defined Under Namespace

Modules: Helper Classes: Condition, GemSpec, GotoScope, IfExistCondition, IfOnlyExistCondition, Instance, ReplaceErbStmtWithExprAction, RubyVersion, Scope, UnlessExistCondition, Warning, WithinScope

Constant Summary collapse

DEFAULT_OPTIONS = 
{ run_instance: true, write_to_file: true, parser: 'parser' }.freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(group, name) { ... } ⇒ Rewriter

Initialize a Rewriter. When a rewriter is initialized, it is already registered.

Parameters:

  • group (String) —

    group of the rewriter.

  • name (String) —

    name of the rewriter.

Yields:

  • defines the behaviors of the rewriter, block code won't be called when initialization.



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# File 'lib/synvert/core/rewriter.rb', line 114

def initialize(group, name, &block)
  @group = group
  @name = name
  @block = block
  @helpers = []
  @sub_snippets = []
  @warnings = []
  @affected_files = Set.new
  @options = DEFAULT_OPTIONS.dup
  @test_results = Hash.new { |h, k| h[k] = [] }
  self.class.register(@group, @name, self)
end

Instance Attribute Details

#affected_files ⇒ Set (readonly)

Returns affected fileds.

Returns:

  • (Set) —

    affected fileds



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# File 'lib/synvert/core/rewriter.rb', line 97

attr_reader :group,
:name,
:sub_snippets,
:helpers,
:warnings,
:affected_files,
:ruby_version,
:gem_spec,
:test_results

#gem_spec ⇒ Rewriter::GemSpec (readonly)

Returns the gem spec.

Returns:



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# File 'lib/synvert/core/rewriter.rb', line 97

attr_reader :group,
:name,
:sub_snippets,
:helpers,
:warnings,
:affected_files,
:ruby_version,
:gem_spec,
:test_results

#group ⇒ String (readonly)

Returns the group of rewriter.

Returns:

  • (String) —

    the group of rewriter



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# File 'lib/synvert/core/rewriter.rb', line 97

def group
  @group
end

#helper ⇒ Array (readonly)

Returns helper methods.

Returns:

  • (Array) —

    helper methods.



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# File 'lib/synvert/core/rewriter.rb', line 97

attr_reader :group,
:name,
:sub_snippets,
:helpers,
:warnings,
:affected_files,
:ruby_version,
:gem_spec,
:test_results

#helpers ⇒ Object (readonly)

Returns the value of attribute helpers.



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# File 'lib/synvert/core/rewriter.rb', line 97

def helpers
  @helpers
end

#name ⇒ String (readonly)

Returns the unique name of rewriter.

Returns:

  • (String) —

    the unique name of rewriter



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# File 'lib/synvert/core/rewriter.rb', line 97

attr_reader :group,
:name,
:sub_snippets,
:helpers,
:warnings,
:affected_files,
:ruby_version,
:gem_spec,
:test_results

#options ⇒ Hash

Returns the rewriter options.

Returns:

  • (Hash) —

    the rewriter options



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# File 'lib/synvert/core/rewriter.rb', line 97

attr_reader :group,
:name,
:sub_snippets,
:helpers,
:warnings,
:affected_files,
:ruby_version,
:gem_spec,
:test_results

#ruby_version ⇒ Rewriter::RubyVersion (readonly)

Returns the ruby version.

Returns:



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# File 'lib/synvert/core/rewriter.rb', line 97

attr_reader :group,
:name,
:sub_snippets,
:helpers,
:warnings,
:affected_files,
:ruby_version,
:gem_spec,
:test_results

#sub_snippets ⇒ Array<Synvert::Core::Rewriter> (readonly)

Returns all rewriters this rewiter calls.

Returns:



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# File 'lib/synvert/core/rewriter.rb', line 97

attr_reader :group,
:name,
:sub_snippets,
:helpers,
:warnings,
:affected_files,
:ruby_version,
:gem_spec,
:test_results

#test_results ⇒ Object (readonly)

Returns the value of attribute test_results.



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# File 'lib/synvert/core/rewriter.rb', line 97

attr_reader :group,
:name,
:sub_snippets,
:helpers,
:warnings,
:affected_files,
:ruby_version,
:gem_spec,
:test_results

#warnings ⇒ Array<Synvert::Core::Rewriter::Warning> (readonly)

Returns warning messages.

Returns:



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# File 'lib/synvert/core/rewriter.rb', line 97

attr_reader :group,
:name,
:sub_snippets,
:helpers,
:warnings,
:affected_files,
:ruby_version,
:gem_spec,
:test_results

Class Method Details

.availables ⇒ Hash<String, Hash<String, Synvert::Core::Rewriter>>

Get all available rewriters

Returns:



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# File 'lib/synvert/core/rewriter.rb', line 61

def availables
  rewriters
end

.clear ⇒ Object

Clear all registered rewriters.



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# File 'lib/synvert/core/rewriter.rb', line 66

def clear
  rewriters.clear
end

.fetch(group, name) ⇒ Synvert::Core::Rewriter

Fetch a rewriter by group and name.

Parameters:

  • group (String) —

    rewrtier group.

  • name (String) —

    rewrtier name.

Returns:



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# File 'lib/synvert/core/rewriter.rb', line 52

def fetch(group, name)
  group = group.to_s
  name = name.to_s
  rewriters.dig(group, name)
end

.register(group, name, rewriter) ⇒ Object

Register a rewriter with its group and name.

Parameters:

  • group (String) —

    the rewriter group.

  • name (String) —

    the unique rewriter name.

  • rewriter (Synvert::Core::Rewriter) —

    the rewriter to register.



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# File 'lib/synvert/core/rewriter.rb', line 40

def register(group, name, rewriter)
  group = group.to_s
  name = name.to_s
  rewriters[group] ||= {}
  rewriters[group][name] = rewriter
end

Instance Method Details

#add_affected_file(file_path) ⇒ Object

Add an affected file.

Parameters:

  • file_path (String) 


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# File 'lib/synvert/core/rewriter.rb', line 179

def add_affected_file(file_path)
  @affected_files.add(file_path)
end

#add_file(filename, content) ⇒ Object

It adds a new file.

Examples:

Synvert::Rewriter.new 'rails', 'add_application_record' do
  add_file 'app/models/application_record.rb', "    class ApplicationRecord < ActiveRecord::Base\n      self.abstract_class = true\n    end\n  EOS\nend\n"

Parameters:

  • filename (String) —

    file name of newly created file.

  • content (String) —

    file body of newly created file.



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# File 'lib/synvert/core/rewriter.rb', line 285

def add_file(filename, content)
  return unless @options[:run_instance]

  unless @options[:write_to_file]
    result = NodeMutation::Result.new(affected: true, conflicted: false)
    if Configuration.test_result == 'new_source'
      result.new_source = content
    else
      result.actions = [NodeMutation::Struct::Action.new(:add_file, 0, 0, content)]
    end
    result.file_path = filename
    merge_test_result(result)
    return
  end

  filepath = File.join(Configuration.root_path, filename)
  if File.exist?(filepath)
    puts "File #{filepath} already exists."
    return
  end

  FileUtils.mkdir_p File.dirname(filepath)
  File.write(filepath, content)
end

#add_snippet(group, name = nil) ⇒ Object

It calls anther rewriter.

Examples:

Synvert::Rewriter.new 'minitest', 'better_syntax' do
  add_snippet 'minitest', 'assert_empty'
  add_snippet 'minitest', 'assert_equal_arguments_order'
  add_snippet 'minitest/assert_instance_of'
  add_snippet 'minitest/assert_kind_of'
  add_snippet '/Users/flyerhzm/.synvert-ruby/lib/minitest/assert_match.rb'
  add_snippet '/Users/flyerhzm/.synvert-ruby/lib/minitest/assert_nil.rb'
  add_snippet 'https://github.com/xinminlabs/synvert-snippets-ruby/blob/main/lib/minitest/assert_silent.rb'
  add_snippet 'https://github.com/xinminlabs/synvert-snippets-ruby/blob/main/lib/minitest/assert_truthy.rb'
end

Parameters:

  • group (String) —

    group of another rewriter, if there's no name parameter, the group can be http url, file path or snippet name.

  • name (String) (defaults to: nil) —

    name of another rewriter.



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# File 'lib/synvert/core/rewriter.rb', line 349

def add_snippet(group, name = nil)
  rewriter =
    if name
      Rewriter.fetch(group, name) || Utils.eval_snippet([group, name].join('/'))
    else
      Utils.eval_snippet(group)
    end
  return unless rewriter && rewriter.is_a?(Rewriter)

  rewriter.options = @options
  if !rewriter.options[:write_to_file]
    results = rewriter.test
    merge_test_results(results)
  elsif rewriter.options[:run_instance]
    rewriter.process
  else
    rewriter.process_with_sandbox
  end
  @sub_snippets << rewriter
end

#add_warning(warning) ⇒ Object

Add a warning.

Parameters:



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# File 'lib/synvert/core/rewriter.rb', line 172

def add_warning(warning)
  @warnings << warning
end

#call_helper(name, options = {}) ⇒ Object

It calls a shared rewriter.

Examples:

Synvert::Rewriter.new 'rails', 'upgrade_6_0_to_6_1' do
  call_helper 'rails/set_load_defaults', rails_version: '6.1'
  add_snippet '/Users/flyerhzm/.synvert-ruby/lib/rails/set_load_defaults.rb', rails_version: '6.1'
  add_snippet 'https://github.com/xinminlabs/synvert-snippets-ruby/blob/main/lib/rails/set_load_defaults.rb', rails_version: '6.1'
end

Parameters:

  • name (String) —

    name of helper.

  • options (Hash) (defaults to: {}) —

    options to pass to helper.



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# File 'lib/synvert/core/rewriter.rb', line 379

def call_helper(name, options = {})
  helper = Synvert::Core::Helper.fetch(name) || Utils.eval_snippet(name)
  return unless helper && helper.is_a?(Synvert::Core::Helper)

  instance_exec(options, &helper.block)
end

#configure(options) ⇒ Object

Configure the rewriter

Examples:

configure({ parser: Synvert::PARSER_PARSER })
configure({ strategy: 'allow_insert_at_same_position' })

Parameters:

  • options (Hash)
  • parser (Hash) —

    a customizable set of options

  • strategy (Hash) —

    a customizable set of options



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# File 'lib/synvert/core/rewriter.rb', line 198

def configure(options)
  @options = @options.merge(options)
  if options[:parser] && ![Synvert::PARSER_PARSER, Synvert::SYNTAX_TREE_PARSER, Synvert::PRISM_PARSER].include?(options[:parser])
    raise Errors::ParserNotSupported.new("Parser #{options[:parser]} not supported")
  end
end

#description(description = nil) ⇒ Object

It sets description of the rewrite or get description.

Examples:

Synvert::Rewriter.new 'rspec', 'use_new_syntax' do
  description 'It converts rspec code to new syntax, it calls all rspec sub snippets.'
end

Parameters:

  • description (String) (defaults to: nil) —

    rewriter description.

Returns:

  • rewriter description.



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# File 'lib/synvert/core/rewriter.rb', line 212

def description(description = nil)
  if description
    @description = description
  else
    @description
  end
end

#helper_method(name) { ... } ⇒ Object

It defines helper method for Instance.

Examples:

Synvert::Rewriter.new 'rails', 'convert_active_record_dirty_5_0_to_5_1' do
  helper_method :find_callbacks_and_convert do |callback_names, callback_changes|
    # do anything, method find_callbacks_and_convert can be reused later.
  end
  within_files Synvert::RAILS_MODEL_FILES + Synvert::RAILS_OBSERVER_FILES do
    find_callbacks_and_convert(before_callback_names, before_callback_changes)
    find_callbacks_and_convert(after_callback_names, after_callback_changes)
  end
end

Parameters:

  • name (String) —

    helper method name.

Yields:

  • helper method block.



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# File 'lib/synvert/core/rewriter.rb', line 399

def helper_method(name, &block)
  @helpers << { name: name, block: block }
end

#if_gem(name, version) ⇒ Object

It compares version of the specified gem.

Examples:

Synvert::Rewriter.new 'rails', 'upgrade_5_2_to_6_0' do
  if_gem 'rails', '>= 6.0'
end

Parameters:

  • name (String) —

    gem name.

  • version (String) —

    equal, less than or greater than specified version, e.g. '>= 2.0.0',



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# File 'lib/synvert/core/rewriter.rb', line 237

def if_gem(name, version)
  @gem_spec = Rewriter::GemSpec.new(name, version)
end

#if_ruby(version) ⇒ Object

It checks if ruby version is greater than or equal to the specified ruby version.

Examples:

Synvert::Rewriter.new 'ruby', 'new_safe_navigation_operator' do
  if_ruby '2.3.0'
end

Parameters:

  • version (String) —

    specified ruby version.



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# File 'lib/synvert/core/rewriter.rb', line 226

def if_ruby(version)
  @ruby_version = Rewriter::RubyVersion.new(version)
end

#parser ⇒ Object 



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# File 'lib/synvert/core/rewriter.rb', line 183

def parser
  @options[:parser]
end

#process ⇒ Object

Process the rewriter. It will call the block.



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# File 'lib/synvert/core/rewriter.rb', line 129

def process
  @affected_files = Set.new
  instance_eval(&@block)
end

#process_with_sandbox ⇒ Object

Process rewriter with sandbox mode. It will call the block but doesn't change any file.



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# File 'lib/synvert/core/rewriter.rb', line 136

def process_with_sandbox
  @options[:run_instance] = false
  process
end

#remove_file(filename) ⇒ Object

It removes a file.

Examples:

Synvert::Rewriter.new 'rails', 'upgrade_4_0_to_4_1' do
  remove_file 'config/initializers/secret_token.rb'
end

Parameters:

  • filename (String) —

    file name.



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# File 'lib/synvert/core/rewriter.rb', line 316

def remove_file(filename)
  return unless @options[:run_instance]

  unless @options[:write_to_file]
    result = NodeMutation::Result.new(affected: true, conflicted: false)
    if Configuration.test_result == 'new_source'
      result.new_source = nil
    else
      result.actions = [NodeMutation::Struct::Action.new(:remove_file, 0, -1)]
    end
    result.file_path = filename
    merge_test_result(result)
    return
  end

  file_path = File.join(Configuration.root_path, filename)
  File.delete(file_path) if File.exist?(file_path)
end

#test ⇒ Object 



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# File 'lib/synvert/core/rewriter.rb', line 141

def test
  @options[:write_to_file] = false
  @affected_files = Set.new
  instance_eval(&@block)

  if Configuration.test_result == 'new_source'
    @test_results.values.flatten
  else
    @test_results.map do |filename, test_results|
      new_actions = test_results.map(&:actions).flatten.sort_by(&:end)
      last_start = -1
      conflicted =
        new_actions.any? do |action|
          if last_start > action.end
            true
          else
            last_start = action.start
            false
          end
        end
      result = NodeMutation::Result.new(affected: true, conflicted: conflicted)
      result.actions = new_actions
      result.file_path = filename
      result
    end
  end
end

#within_files(file_patterns, &block) ⇒ Object Also known as: within_file

It finds specified files, and for each file, it will delegate to Instance to rewrite code. It creates a Instance to rewrite code.

Examples:

Synvert::Rewriter.new 'rspec', 'be_close_to_be_within' do
  within_files '**/*.rb' do
  end
end

Parameters:

  • file_patterns (String|Array<String>) —

    string pattern or list of string pattern to find files, e.g. ['spec/*/_spec.rb']

  • block (Block) —

    the block to rewrite code in the matching files.



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# File 'lib/synvert/core/rewriter.rb', line 250

def within_files(file_patterns, &block)
  return unless @options[:run_instance]

  return if @ruby_version && !@ruby_version.match?
  return if @gem_spec && !@gem_spec.match?

  if @options[:write_to_file]
    handle_one_file(Array(file_patterns)) do |file_path|
      instance = Instance.new(self, file_path, &block)
      instance.process
    end
  else
    results =
      handle_one_file(Array(file_patterns)) do |file_path|
        instance = Instance.new(self, file_path, &block)
        instance.test
      end
    merge_test_results(results)
  end
end