Class: Shirobai::Cop::Style::RedundantSelfAssignment

Inherits:
RuboCop::Cop::Base
  • Object
show all
Extended by:
RuboCop::Cop::AutoCorrector
Defined in:
lib/shirobai/cop/style/redundant_self_assignment.rb

Overview

Drop-in Rust reimplementation of Style/RedundantSelfAssignment.

Detection and autocorrect both happen in Rust; Ruby turns each tuple into an offense and a corrector.replace / corrector.remove op. METHODS_RETURNING_SELF is closed and copied verbatim into the Rust rule, so the cop is config-less (bundle_args returns []).

Two kinds of offenses come back:

  • kind = 0 (variable assignment, var = var.<METHOD!>(...)): replace [range_start, range_end) with source[rhs_start..rhs_end] (drop the var = prefix, leave the rhs source intact — stock does the same via corrector.replace(node, rhs.source)).
  • kind = 1 (setter, obj.foo = obj.foo.<METHOD!>(...)): delete [range_start, range_end), which is the obj.foo = prefix (stock's corrector.remove(range_between(node_start, first_arg_start))).

Constant Summary collapse

MSG = 
"Redundant self assignment detected. " \
"Method `%<method_name>s` modifies its receiver in place."

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.badge ⇒ Object 



28
 
# File 'lib/shirobai/cop/style/redundant_self_assignment.rb', line 28

def self.badge = RuboCop::Cop::Badge.parse("Style/RedundantSelfAssignment")

.bundle_args(_config) ⇒ Object

Config-less from the Rust side — the destructive method set is a closed list in crates/shirobai-core/src/rules/redundant_self_assignment.rs.



32
 
# File 'lib/shirobai/cop/style/redundant_self_assignment.rb', line 32

def self.bundle_args(_config) = []

.cop_name ⇒ Object 



27
 
# File 'lib/shirobai/cop/style/redundant_self_assignment.rb', line 27

def self.cop_name = "Style/RedundantSelfAssignment"

Instance Method Details

#on_new_investigation ⇒ Object 



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# File 'lib/shirobai/cop/style/redundant_self_assignment.rb', line 34

def on_new_investigation
  offenses = Dispatch.offenses_for(processed_source, config, :redundant_self_assignment)
  return if offenses.empty?

  off = SourceOffsets.for(processed_source.raw_source)
  buffer = processed_source.buffer
  source = processed_source.raw_source

  offenses.each do |op_start, op_end, method_name, kind, range_start, range_end, rhs_start, rhs_end|
    op_range = Parser::Source::Range.new(buffer, off[op_start], off[op_end])
    message = format(MSG, method_name: method_name)
    add_offense(op_range, message: message) do |corrector|
      target = Parser::Source::Range.new(buffer, off[range_start], off[range_end])
      if kind == 0
        # Variable assignment: replace the whole `var = var.foo(args)`
        # node with the rhs source `var.foo(args)`.
        replacement = source.byteslice(rhs_start, rhs_end - rhs_start)
        corrector.replace(target, replacement)
      else
        # Setter: remove the `obj.foo = ` prefix in place.
        corrector.remove(target)
      end
    end
  end
end