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::BASIC_LITERALS, Node::COMPARISON_OPERATORS, Node::COMPOSITE_LITERALS, Node::FALSEY_LITERALS, Node::IMMUTABLE_LITERALS, Node::KEYWORDS, Node::LITERALS, Node::MUTABLE_LITERALS, Node::OPERATOR_KEYWORDS, Node::REFERENCES, 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, #argument?, #asgn_method_call?, #basic_literal?, #binary_operation?, #chained?, #child_nodes, #complete!, #complete?, #const_name, def_matcher, #defined_module, #defined_module_name, #descendants, #each_ancestor, #each_child_node, #each_descendant, #each_node, #falsey_literal?, #immutable_literal?, #initialize, #keyword?, #keyword_bang?, #keyword_not?, #literal?, #multiline?, #mutable_literal?, #numeric_type?, #parent, #parent_module_name, #pure?, #receiver, #reference?, #sibling_index, #single_line?, #source, #source_range, #special_keyword?, #truthy_literal?, #unary_operation?, #updated, #value_used?, #variable?

Methods included from Sexp

#s

Constructor Details

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

Instance Method Details

#else? ⇒ Boolean

Note:

This returns true for nodes containing an elsif clause. This is legacy behaviour, 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 42

def else?
  loc.respond_to?(: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



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# File 'lib/rubocop/ast/node/if_node.rb', line 117

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 32

def elsif?
  keyword == '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



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# File 'lib/rubocop/ast/node/if_node.rb', line 107

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 66

def inverse_keyword
  if keyword == 'if'
    'unless'
  elsif keyword == 'unless'
    '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 57

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 81

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

#nested_conditional? ⇒ Boolean

Note:

This is a shallow search.

Chackes 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 91

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 125

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 49

def ternary?
  loc.respond_to?(:question)
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