Class: Synvert::Core::Rewriter::Instance

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

Overview

Instance is an execution unit, it finds specified ast nodes, checks if the nodes match some conditions, then add, replace or remove code.

One instance can contain one or many Scope and Condition.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Helper

#add_arguments_with_parenthesis_if_necessary, #add_curly_brackets_if_necessary, #add_receiver_if_necessary, #reject_keys_from_hash, #strip_brackets

Constructor Details

#initialize(rewriter, file_path) { ... } ⇒ Instance

Initialize an Instance.

Parameters:

Yields:

  • block code to find nodes, match conditions and rewrite code.



16
17
18
19
20
21
22
23
24
25
26
27
 
# File 'lib/synvert/core/rewriter/instance.rb', line 16

def initialize(rewriter, file_path, &block)
  @rewriter = rewriter
  @actions = []
  @file_path = file_path
  @block = block
  strategy = NodeMutation::Strategy::KEEP_RUNNING
  if rewriter.options[:strategy] == Strategy::ALLOW_INSERT_AT_SAME_POSITION
    strategy |=  NodeMutation::Strategy::ALLOW_INSERT_AT_SAME_POSITION
  end
  NodeMutation.configure({ strategy: strategy })
  rewriter.helpers.each { |helper| singleton_class.send(:define_method, helper[:name], &helper[:block]) }
end

Instance Attribute Details

#current_node ⇒ Object

Returns current ast node.

Returns:

  • current ast node



35
 
# File 'lib/synvert/core/rewriter/instance.rb', line 35

attr_reader :file_path, :current_node, :mutation_adapter

#file_path ⇒ Object (readonly)

Returns file path.

Returns:

  • file path



35
36
37
 
# File 'lib/synvert/core/rewriter/instance.rb', line 35

def file_path
  @file_path
end

#mutation_adapter ⇒ Object (readonly)

Returns the value of attribute mutation_adapter.



35
 
# File 'lib/synvert/core/rewriter/instance.rb', line 35

attr_reader :file_path, :current_node, :mutation_adapter

Instance Method Details

#add_action(action) ⇒ Object

Add a custom action.

Examples:

remover_action = NodeMutation::RemoveAction.new(node)
add_action(remover_action)

Parameters:

  • action (Synvert::Core::Rewriter::Action) —

    action



399
400
401
 
# File 'lib/synvert/core/rewriter/instance.rb', line 399

def add_action(action)
  @current_mutation.actions << action.process
end

#append(code) ⇒ Object

It appends the code to the bottom of current node body.

Examples:

# def teardown
#   clean_something
# end
# =>
# def teardown
#   clean_something
#   super
# end
with_node type: 'def', name: 'steardown' do
  append 'super'
end

Parameters:

  • code (String) —

    code need to be appended.



237
238
239
 
# File 'lib/synvert/core/rewriter/instance.rb', line 237

def append(code)
  @current_mutation.append(@current_node, code)
end

#delete(*selectors, **options) ⇒ Object

It deletes child nodes.

Examples:

# FactoryBot.create(...)
# =>
# create(...)
with_node type: 'send', receiver: 'FactoryBot', message: 'create' do
  delete :receiver, :dot
end

Parameters:

  • selectors (Array<Symbol>) —

    selector names of child node.

  • options (Hash)
  • and_comma (Hash) —

    a customizable set of options



368
369
370
 
# File 'lib/synvert/core/rewriter/instance.rb', line 368

def delete(*selectors, **options)
  @current_mutation.delete(@current_node, *selectors, **options)
end

#goto_node(child_node_name, &block) ⇒ Object

It creates a GotoScope to go to a child node, then continue operating on the child node.

Examples:

# head status: 406
with_node type: 'send', receiver: nil, message: 'head', arguments: { size: 1, first: { type: 'hash' } } do
  goto_node 'arguments.first' do
  end
end

Parameters:

  • child_node_name (Symbol|String) —

    the name of the child nodes.

  • block (Block) —

    block code to continue operating on the matching nodes.



176
177
178
 
# File 'lib/synvert/core/rewriter/instance.rb', line 176

def goto_node(child_node_name, &block)
  Rewriter::GotoScope.new(self, child_node_name, &block).process
end

#if_exist_node(nql_or_rules, &block) ⇒ Object

It creates a Synvert::Core::Rewriter::IfExistCondition to check if matching nodes exist in the child nodes, if so, then continue operating on each matching ast node.

Examples:

# Klass.any_instance.stub(:message)
with_node type: 'send', message: 'stub', arguments: { first: { type: { not: 'hash' } } } do
  if_exist_node type: 'send', message: 'any_instance' do
  end
end

Parameters:

  • nql_or_rules (String|Hash) —

    nql or rules to check mathing ast nodes.

  • block (Block) —

    block code to continue operating on the matching nodes.



190
191
192
 
# File 'lib/synvert/core/rewriter/instance.rb', line 190

def if_exist_node(nql_or_rules, &block)
  Rewriter::IfExistCondition.new(self, nql_or_rules, &block).process
end

#if_only_exist_node(nql_or_rules, &block) ⇒ Object

It creates a Synvert::Core::Rewriter::IfOnlyExistCondition to check if current node has only one child node and the child node matches, if so, then continue operating on each matching ast node.

Examples:

# it { should matcher }
with_node type: 'block', caller: { message: 'it' } do
  if_only_exist_node type: 'send', receiver: nil, message: 'should' do
  end
end

Parameters:

  • nql_or_rules (String|Hash) —

    nql or rules to check mathing ast nodes.

  • block (Block) —

    block code to continue operating on the matching nodes.



219
220
221
 
# File 'lib/synvert/core/rewriter/instance.rb', line 219

def if_only_exist_node(nql_or_rules, &block)
  Rewriter::IfOnlyExistCondition.new(self, nql_or_rules, &block).process
end

#insert(code, at: 'end', to: nil) ⇒ Object

It inserts code.

Examples:

# open('http://test.com')
# =>
# URI.open('http://test.com')
with_node type: 'send', receiver: nil, message: 'open' do
  insert 'URI.', at: 'beginning'
end

Parameters:

  • code (String) —

    code need to be inserted.

  • at (String) (defaults to: 'end') —

    insert position, beginning or end

  • to (String) (defaults to: nil) —

    where to insert, if it is nil, will insert to current node.



270
271
272
 
# File 'lib/synvert/core/rewriter/instance.rb', line 270

def insert(code, at: 'end', to: nil)
  @current_mutation.insert(@current_node, code, at: at, to: to)
end

#insert_after(code, to: nil) ⇒ Object

It inserts the code next to the current node.

Examples:

# Synvert::Application.config.secret_token = "0447aa931d42918bfb934750bb78257088fb671186b5d1b6f9fddf126fc8a14d34f1d045cefab3900751c3da121a8dd929aec9bafe975f1cabb48232b4002e4e"
# =>
# Synvert::Application.config.secret_token = "0447aa931d42918bfb934750bb78257088fb671186b5d1b6f9fddf126fc8a14d34f1d045cefab3900751c3da121a8dd929aec9bafe975f1cabb48232b4002e4e"
# Synvert::Application.config.secret_key_base = "bf4f3f46924ecd9adcb6515681c78144545bba454420973a274d7021ff946b8ef043a95ca1a15a9d1b75f9fbdf85d1a3afaf22f4e3c2f3f78e24a0a188b581df"
with_node type: 'send', message: 'secret_token=' do
  insert_after "{{receiver}}.secret_key_base = \"#{SecureRandom.hex(64)}\""
end

Parameters:

  • code (String) —

    code need to be inserted.



284
285
286
287
 
# File 'lib/synvert/core/rewriter/instance.rb', line 284

def insert_after(code, to: nil)
  column = ' ' * NodeMutation.adapter.get_start_loc(@current_node).column
  @current_mutation.insert(@current_node, "\n#{column}#{code}", at: 'end', to: to)
end

#insert_before(code, to: nil) ⇒ Object

It inserts the code previous to the current node.

Examples:

# Synvert::Application.config.secret_token = "0447aa931d42918bfb934750bb78257088fb671186b5d1b6f9fddf126fc8a14d34f1d045cefab3900751c3da121a8dd929aec9bafe975f1cabb48232b4002e4e"
# =>
# Synvert::Application.config.secret_key_base = "bf4f3f46924ecd9adcb6515681c78144545bba454420973a274d7021ff946b8ef043a95ca1a15a9d1b75f9fbdf85d1a3afaf22f4e3c2f3f78e24a0a188b581df"
# Synvert::Application.config.secret_token = "0447aa931d42918bfb934750bb78257088fb671186b5d1b6f9fddf126fc8a14d34f1d045cefab3900751c3da121a8dd929aec9bafe975f1cabb48232b4002e4e"
with_node type: 'send', message: 'secret_token=' do
  insert_before "{{receiver}}.secret_key_base = \"#{SecureRandom.hex(64)}\""
end

Parameters:

  • code (String) —

    code need to be inserted.



299
300
301
302
 
# File 'lib/synvert/core/rewriter/instance.rb', line 299

def insert_before(code, to: nil)
  column = ' ' * NodeMutation.adapter.get_start_loc(@current_node).column
  @current_mutation.insert(@current_node, "#{code}\n#{column}", at: 'beginning', to: to)
end

#node ⇒ Parser::AST::Node

Gets current node, it allows to get current node in block code.

Returns:



113
114
115
 
# File 'lib/synvert/core/rewriter/instance.rb', line 113

def node
  @current_node
end

#noop ⇒ Object

No operation.



390
391
392
 
# File 'lib/synvert/core/rewriter/instance.rb', line 390

def noop
  @current_mutation.noop(@current_node)
end

#prepend(code) ⇒ Object

It prepends the code to the top of current node body.

Examples:

# def setup
#   do_something
# end
# =>
# def setup
#   super
#   do_something
# end
with_node type: 'def', name: 'setup' do
  prepend 'super'
end

Parameters:

  • code (String) —

    code need to be prepended.



255
256
257
 
# File 'lib/synvert/core/rewriter/instance.rb', line 255

def prepend(code)
  @current_mutation.prepend(@current_node, code)
end

#process ⇒ Object

Process the instance. It finds specified files, for each file, it executes the block code, rewrites the original code, then writes the code back to the original file.



41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
 
# File 'lib/synvert/core/rewriter/instance.rb', line 41

def process
  puts @file_path if Configuration.show_run_process

  absolute_file_path = File.join(Configuration.root_path, @file_path)
  while true
    source = read_source(absolute_file_path)
    @current_mutation = NodeMutation.new(source)
    @mutation_adapter = NodeMutation.adapter
    begin
      node = parse_code(@file_path, source)

      process_with_node(node) do
        instance_eval(&@block)
      rescue NoMethodError => e
        puts [
          "error: #{e.message}",
          "file: #{file_path}",
          "source: #{source}",
          "line: #{current_node.line}"
        ].join("\n")
        raise
      end

      result = @current_mutation.process
      if result.affected?
        @rewriter.add_affected_file(file_path)
        write_source(absolute_file_path, result.new_source)
      end
      break unless result.conflicted?
    rescue Parser::SyntaxError
      puts "[Warn] file #{file_path} was not parsed correctly."
      # do nothing, iterate next file
    end
  end
end

#process_with_node(node) { ... } ⇒ Object

Set current_node to node and process.

Parameters:

Yields:

  • process



121
122
123
124
125
 
# File 'lib/synvert/core/rewriter/instance.rb', line 121

def process_with_node(node)
  self.current_node = node
  yield
  self.current_node = node
end

#process_with_other_node(node) { ... } ⇒ Object

Set current_node properly, process and set current_node back to original current_node.

Parameters:

Yields:

  • process



131
132
133
134
135
136
 
# File 'lib/synvert/core/rewriter/instance.rb', line 131

def process_with_other_node(node)
  original_node = current_node
  self.current_node = node
  yield
  self.current_node = original_node
end

#remove(**options) ⇒ Object

It removes current node.

Examples:

with_node type: 'send', message: { in: %w[puts p] } do
  remove
end

Parameters:

  • options (Hash) —

    options.

  • and_comma (Hash) —

    a customizable set of options



353
354
355
 
# File 'lib/synvert/core/rewriter/instance.rb', line 353

def remove(**options)
  @current_mutation.remove(@current_node, **options)
end

#replace(*selectors, with:) ⇒ Object

It replaces the code of specified child nodes.

Examples:

# assert(object.empty?)
# =>
# assert_empty(object)
with_node type: 'send', receiver: nil, message: 'assert', arguments: { size: 1, first: { type: 'send', message: 'empty?', arguments: { size: 0 } } } do
  replace :message, with: 'assert_empty'
  replace :arguments, with: '{{arguments.first.receiver}}'
end

Parameters:

  • selectors (Array<Symbol>) —

    selector names of child node.

  • with (String) —

    code need to be replaced with.



342
343
344
 
# File 'lib/synvert/core/rewriter/instance.rb', line 342

def replace(*selectors, with:)
  @current_mutation.replace(@current_node, *selectors, with: with)
end

#replace_erb_stmt_with_expr ⇒ Object

It replaces erb stmt code to expr code.

Examples:

# <% form_for post do |f| %>
# <% end %>
# =>
# <%= form_for post do |f| %>
# <% end %>
with_node type: 'block', caller: { type: 'send', receiver: nil, message: 'form_for' } do
  replace_erb_stmt_with_expr
end



314
315
316
 
# File 'lib/synvert/core/rewriter/instance.rb', line 314

def replace_erb_stmt_with_expr
  @current_mutation.actions << Rewriter::ReplaceErbStmtWithExprAction.new(@current_node).process
end

#replace_with(code) ⇒ Object

It replaces the whole code of current node.

Examples:

# obj.stub(:foo => 1, :bar => 2)
# =>
# allow(obj).to receive_messages(:foo => 1, :bar => 2)
with_node type: 'send', message: 'stub', arguments: { first: { type: 'hash' } } do
  replace_with 'allow({{receiver}}).to receive_messages({{arguments}})'
end

Parameters:

  • code (String) —

    code need to be replaced with.



327
328
329
 
# File 'lib/synvert/core/rewriter/instance.rb', line 327

def replace_with(code)
  @current_mutation.replace_with(@current_node, code)
end

#test ⇒ Object

Test the instance. It finds specified files, for each file, it executes the block code, tests the original code, then returns the actions.



80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
 
# File 'lib/synvert/core/rewriter/instance.rb', line 80

def test
  absolute_file_path = File.join(Configuration.root_path, file_path)
  source = read_source(absolute_file_path)
  @current_mutation = NodeMutation.new(source)
  @mutation_adapter = NodeMutation.adapter
  begin
    node = parse_code(file_path, source)

    process_with_node(node) do
      instance_eval(&@block)
    rescue NoMethodError => e
      puts [
        "error: #{e.message}",
        "file: #{file_path}",
        "source: #{source}",
        "line: #{current_node.line}"
      ].join("\n")
      raise
    end

    result = @current_mutation.test
    result.file_path = file_path
    result
  rescue Parser::SyntaxError
    puts "[Warn] file #{file_path} was not parsed correctly."
    # do nothing, iterate next file
  end
end

#unless_exist_node(nql_or_rules, &block) ⇒ Object

It creates a UnlessExistCondition to check if matching nodes doesn't exist in the child nodes, if so, then continue operating on each matching ast node.

Examples:

# obj.stub(:message)
with_node type: 'send', message: 'stub', arguments: { first: { type: { not: 'hash' } } } do
  unless_exist_node type: 'send', message: 'any_instance' do
  end
end

Parameters:

  • nql_or_rules (String|Hash) —

    nql or rules to check mathing ast nodes.

  • block (Block) —

    block code to continue operating on the matching nodes.



204
205
206
 
# File 'lib/synvert/core/rewriter/instance.rb', line 204

def unless_exist_node(nql_or_rules, &block)
  Rewriter::UnlessExistCondition.new(self, nql_or_rules, &block).process
end

#warn(message) ⇒ Object

It creates a Warning to save warning message.

Examples:

within_files 'vendor/plugins' do
  warn 'Rails::Plugin is deprecated and will be removed in Rails 4.0. Instead of adding plugins to vendor/plugins use gems or bundler with path or git dependencies.'
end

Parameters:

  • message (String) —

    warning message.



409
410
411
 
# File 'lib/synvert/core/rewriter/instance.rb', line 409

def warn(message)
  @rewriter.add_warning Rewriter::Warning.new(self, message)
end

#within_node(nql_or_rules, options = {}) { ... } ⇒ Object Also known as: with_node, find_node

It creates a WithinScope to recursively find matching ast nodes, then continue operating on each matching ast node.

Examples:

# matches User.find_by_login('test')
with_node type: 'send', message: /^find_by_/ do
end
# matches FactoryBot.create(:user)
with_node '.send[receiver=FactoryBot][message=create][arguments.size=1]' do
end

Parameters:

  • nql_or_rules (String|Hash) —

    nql or rules to find mathing ast nodes.

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

    optional

  • including_self (Hash) —

    a customizable set of options

  • stop_at_first_match (Hash) —

    a customizable set of options

  • recursive (Hash) —

    a customizable set of options

Yields:

  • run on the matching nodes.



157
158
159
160
161
 
# File 'lib/synvert/core/rewriter/instance.rb', line 157

def within_node(nql_or_rules, options = {}, &block)
  Rewriter::WithinScope.new(self, nql_or_rules, options, &block).process
rescue NodeQueryLexer::ScanError, Racc::ParseError => e
  raise NodeQuery::Compiler::ParseError, "Invalid query string: #{nql_or_rules}"
end

#wrap(with:) ⇒ Object

It wraps current node with code.

Examples:

# class Foobar
# end
# =>
# module Synvert
#   class Foobar
#   end
# end
within_node type: 'class' do
  wrap with: 'module Synvert'
end

Parameters:

  • with (String) —

    code need to be wrapped with.



385
386
387
 
# File 'lib/synvert/core/rewriter/instance.rb', line 385

def wrap(with:)
  @current_mutation.wrap(@current_node, with: with)
end

#wrap_with_quotes(str) ⇒ String

Wrap str string with single or doulbe quotes based on Configuration.single_quote.

Parameters:

  • str (String)

Returns:

  • (String) —

    quoted string



416
417
418
419
420
421
422
423
424
 
# File 'lib/synvert/core/rewriter/instance.rb', line 416

def wrap_with_quotes(str)
  quote = Configuration.single_quote ? "'" : '"';
  another_quote = Configuration.single_quote ? '"' : "'";
  if str.include?(quote) && !str.include?(another_quote)
    return "#{another_quote}#{str}#{another_quote}"
  end
  escaped_str = str.gsub(quote) { |char| '\\' + quote }
  quote + escaped_str + quote
end