Class: RuboCop::AST::IfNode

Inherits:
Node
  • Object
show all
Includes:
ConditionalNode, ModifierNode
Defined in:
lib/rubocop/ast/node/if_node.rb

Overview

A node extension for if nodes. This will be used in place of a plain node when the builder constructs the AST, making its methods available to all if nodes within RuboCop.

Constant Summary

Constants inherited from Node

Node::ASSIGNMENTS, Node::BASIC_CONDITIONALS, Node::BASIC_LITERALS, Node::COMPARISON_OPERATORS, Node::COMPOSITE_LITERALS, Node::CONDITIONALS, Node::EQUALS_ASSIGNMENTS, Node::FALSEY_LITERALS, Node::IMMUTABLE_LITERALS, Node::KEYWORDS, Node::LITERALS, Node::LOOP_TYPES, Node::MUTABLE_LITERALS, Node::OPERATOR_KEYWORDS, Node::POST_CONDITION_LOOP_TYPES, Node::REFERENCES, Node::SHORTHAND_ASSIGNMENTS, Node::SPECIAL_KEYWORDS, Node::TRUTHY_LITERALS, Node::VARIABLES

Instance Method Summary collapse

Methods included from ConditionalNode

#body, #condition, #multiline_condition?, #single_line_condition?

Methods inherited from Node

#ancestors, #any_block_type?, #any_def_type?, #any_match_pattern_type?, #any_str_type?, #any_sym_type?, #argument?, #argument_type?, #assignment?, #assignment_or_similar?, #basic_conditional?, #basic_literal?, #boolean_type?, #call_type?, #chained?, #class_constructor?, #class_definition?, #complete!, #complete?, #conditional?, #const_name, #defined_module, #defined_module_name, #each_ancestor, #empty_source?, #equals_asgn?, #falsey_literal?, #first_line, #global_const?, #guard_clause?, #immutable_literal?, #initialize, #keyword?, #lambda?, #lambda_or_proc?, #last_line, #left_sibling, #left_siblings, #line_count, #literal?, #loc?, #loc_is?, #loop_keyword?, #match_guard_clause?, #module_definition?, #multiline?, #mutable_literal?, #nonempty_line_count, #numeric_type?, #operator_keyword?, #parent, #parent?, #parent_module_name, #parenthesized_call?, #post_condition_loop?, #proc?, #pure?, #range_type?, #receiver, #recursive_basic_literal?, #recursive_literal?, #reference?, #right_sibling, #right_siblings, #root?, #send_type?, #shorthand_asgn?, #sibling_index, #single_line?, #source, #source_length, #source_range, #special_keyword?, #str_content, #struct_constructor?, #truthy_literal?, #type?, #updated, #value_used?, #variable?

Methods included from NodePattern::Macros

#def_node_matcher, #def_node_search

Methods included from Descendence

#child_nodes, #descendants, #each_child_node, #each_descendant, #each_node

Methods included from Sexp

#s

Constructor Details

This class inherits a constructor from RuboCop::AST::Node

Instance Method Details

#branches ⇒ Array<Node>

Returns an array of all the branches in the conditional statement.

Returns:

  • (Array<Node>) —

    an array of branch nodes



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# File 'lib/rubocop/ast/node/if_node.rb', line 154

def branches
  if ternary?
    [if_branch, else_branch]
  elsif !else?
    [if_branch]
  else
    branches = [if_branch]
    other_branches = if elsif_conditional?
                       else_branch.branches
                     else
                       [else_branch]
                     end
    branches.concat(other_branches)
  end
end

#each_branch(&block) ⇒ Object

Deprecated.

Use branches.each



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# File 'lib/rubocop/ast/node/if_node.rb', line 171

def each_branch(&block)
  return branches.to_enum(__method__) unless block

  branches.each(&block)
end

#else? ⇒ Boolean

Note:

This returns true for nodes containing an elsif clause. This is legacy behavior, and many cops rely on it.

Checks whether the if node has an else clause.

Returns:

  • (Boolean) —

    whether the node has an else clause



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# File 'lib/rubocop/ast/node/if_node.rb', line 49

def else?
  loc?(:else)
end

#else_branch ⇒ Node?

Note:

This is normalized for unless nodes.

Returns the branch of the if node that gets evaluated when its condition is falsey.

Returns:

  • (Node) —

    the falsey branch node of the if node

  • (nil) —

    when there is no else branch



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# File 'lib/rubocop/ast/node/if_node.rb', line 133

def else_branch
  node_parts[2]
end

#elsif? ⇒ Boolean

Checks whether the if is an elsif. Parser handles these by nesting if nodes in the else branch.

Returns:

  • (Boolean) —

    whether the node is an elsif



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# File 'lib/rubocop/ast/node/if_node.rb', line 39

def elsif?
  keyword == 'elsif'
end

#elsif_conditional? ⇒ Boolean

Checks whether the if node has at least one elsif branch. Returns true if this if node itself is an elsif.

Returns:

  • (Boolean) —

    whether the if node has at least one elsif branch



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# File 'lib/rubocop/ast/node/if_node.rb', line 111

def elsif_conditional?
  else_branch&.if_type? && else_branch.elsif?
end

#if? ⇒ Boolean

Checks whether this node is an if statement. (This is not true of ternary operators and unless statements.)

Returns:

  • (Boolean) —

    whether the node is an if statement



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# File 'lib/rubocop/ast/node/if_node.rb', line 16

def if?
  keyword == 'if'
end

#if_branch ⇒ Node?

Note:

This is normalized for unless nodes.

Returns the branch of the if node that gets evaluated when its condition is truthy.

Returns:

  • (Node) —

    the truthy branch node of the if node

  • (nil) —

    if the truthy branch is empty



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# File 'lib/rubocop/ast/node/if_node.rb', line 122

def if_branch
  node_parts[1]
end

#inverse_keyword ⇒ String

Returns the inverse keyword of the if node as a string. Returns if for unless nodes and vice versa. Returns an empty string for ternary operators.

Returns:

  • (String) —

    the inverse keyword of the if statement



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# File 'lib/rubocop/ast/node/if_node.rb', line 73

def inverse_keyword
  case keyword
  when 'if' then 'unless'
  when 'unless' then 'if'
  else
    ''
  end
end

#keyword ⇒ String

Returns the keyword of the if statement as a string. Returns an empty string for ternary operators.

Returns:

  • (String) —

    the keyword of the if statement



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# File 'lib/rubocop/ast/node/if_node.rb', line 64

def keyword
  ternary? ? '' : loc.keyword.source
end

#modifier_form? ⇒ Boolean

Checks whether the if node is in a modifier form, i.e. a condition trailing behind an expression. Only if and unless nodes without other branches can be modifiers.

Returns:

  • (Boolean) —

    whether the if node is a modifier



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# File 'lib/rubocop/ast/node/if_node.rb', line 87

def modifier_form?
  (if? || unless?) && super
end

#nested_conditional? ⇒ Boolean

Note:

This performs a shallow search.

Checks whether the if node has nested if nodes in any of its branches.

Returns:

  • (Boolean) —

    whether the if node contains nested conditionals



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# File 'lib/rubocop/ast/node/if_node.rb', line 97

def nested_conditional?
  node_parts[1..2].compact.each do |branch|
    branch.each_node(:if) do |nested|
      return true unless nested.elsif?
    end
  end

  false
end

#node_parts ⇒ Array<Node>

Custom destructuring method. This is used to normalize the branches for if and unless nodes, to aid comparisons and conversions.

Returns:

  • (Array<Node>) —

    the different parts of the if statement



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# File 'lib/rubocop/ast/node/if_node.rb', line 141

def node_parts
  if unless?
    condition, false_branch, true_branch = *self
  else
    condition, true_branch, false_branch = *self
  end

  [condition, true_branch, false_branch]
end

#ternary? ⇒ Boolean

Checks whether the if node is a ternary operator.

Returns:

  • (Boolean) —

    whether the if node is a ternary operator



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# File 'lib/rubocop/ast/node/if_node.rb', line 56

def ternary?
  loc?(:question)
end

#then? ⇒ Boolean

Checks whether the if node has an then clause.

Returns:

  • (Boolean) —

    whether the node has an then clause



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# File 'lib/rubocop/ast/node/if_node.rb', line 31

def then?
  loc_is?(:begin, 'then')
end

#unless? ⇒ Boolean

Checks whether this node is an unless statement. (This is not true of ternary operators and if statements.)

Returns:

  • (Boolean) —

    whether the node is an unless statement



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# File 'lib/rubocop/ast/node/if_node.rb', line 24

def unless?
  keyword == 'unless'
end