Add introspection utilities for Reline keybindings and IRB command to… by Syati · Pull Request #4 · Syati/reline_pac

Syati · 2026-01-17T13:01:56Z

… display them

Copilot

Pull request overview

This pull request adds introspection utilities for Reline keybindings and an IRB command to display them. The PR introduces functionality to inspect and format Reline keybindings in a human-readable way, along with an interactive IRB command interface.

Changes:

Added introspection module to query and format Reline keybindings with special key symbols
Created an IRB command to display keybindings in a formatted table
Added comprehensive test coverage for the introspection functionality

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 8 comments.

File	Description
lib/reline_pac/introspection.rb	Implements keymap inspection and key sequence formatting with support for control keys, arrow keys, and special characters
lib/reline_pac/irb_commands.rb	Defines an IRB command class to display keybindings in a formatted output
spec/reline_pac/introspection_spec.rb	Provides test coverage for the introspection module's keymap functionality
lib/reline_pac.rb	Integrates the new introspection module and conditionally loads IRB commands

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Copilot · 2026-01-17T13:05:00Z

+        case byte
+        when 27
+          '⎋'
+        when 0..31 # Control キー


The comment on line 78 contains Japanese text ('Control キー' meaning 'Control key'). For consistency with the rest of the codebase where English is used, this comment should be written in English.

Suggested change

when 0..31 # Control キー

when 0..31 # Control key

Copilot · 2026-01-17T13:05:00Z

+    it 'includes known keybindings' do
+      result = described_class.keymap
+      # Control-A should map to ed_move_to_beg
+      expect(result).to include('⌃A' => :ed_move_to_beg)


The test expects Control-A (⌃A) to always map to ed_move_to_beg, but this assumption depends on the default Reline configuration and may vary across different environments or Reline versions. This could make the test brittle. Consider either mocking the keymap data or testing the formatting logic independently of specific keybinding values.

Suggested change

it 'includes known keybindings' do

result = described_class.keymap

# Control-A should map to ed_move_to_beg

expect(result).to include('⌃A' => :ed_move_to_beg)

it 'includes and formats movement keybindings when present' do

result = described_class.keymap

# If ed_move_to_beg is present, its key should be formatted as a Control key

key_for_move_to_beg = result.key(:ed_move_to_beg)

if key_for_move_to_beg

expect(key_for_move_to_beg).to include('⌃')

end

Copilot · 2026-01-17T13:05:00Z

+# Load commands only if IRB is available
+require_relative 'reline_pac/irb_commands' if defined?(IRB)


The conditional require 'require_relative 'reline_pac/irb_commands' if defined?(IRB)' may not work as intended in all scenarios. The file itself requires 'irb' at the top (line 3 of irb_commands.rb), which means if IRB is not available when this line executes, it will raise a LoadError. The conditional should either wrap the require statement in the irb_commands.rb file or use a rescue block here to handle cases where IRB is not installed.

Suggested change

# Load commands only if IRB is available

require_relative 'reline_pac/irb_commands' if defined?(IRB)

# Load commands only if IRB is available, and fail gracefully if IRB cannot be loaded

begin

require_relative 'reline_pac/irb_commands' if defined?(IRB)

rescue LoadError

# IRB is not installed or could not be loaded; skip IRB-specific commands

end

Copilot · 2026-01-17T13:05:01Z

+
+      def execute(_arg)
+        bindings = RelinePac::Introspection.keymap
+        max_key_length = bindings.keys.map(&:length).max


The execute method doesn't handle the case where bindings is empty or max_key_length is nil. If keymap returns an empty hash, bindings.keys.map(&:length).max will return nil, and calling ljust on a string with nil as an argument will raise a TypeError.

Suggested change

max_key_length = bindings.keys.map(&:length).max

max_key_length = bindings.keys.map(&:length).max || 0

Copilot · 2026-01-17T13:05:01Z

+    class Keybinds < ::IRB::Command::Base
+      category 'Context'
+      description 'Show Reline keybindings'
+
+      def execute(_arg)
+        bindings = RelinePac::Introspection.keymap
+        max_key_length = bindings.keys.map(&:length).max
+
+        bindings.each do |key, method|
+          puts "#{key.ljust(max_key_length + 2)} #{method}"
+        end
+      end
+    end


The test cases don't cover the IrbCommands::Keybinds class, which means the execute method and command registration logic lacks test coverage. Since other modules in the repo have corresponding test files, this command should also have tests.

Copilot · 2026-01-17T13:05:01Z

+        config = Reline.core.config
+        bindings = {}
+
+        config.keymap.instance_variable_get(:@key_bindings).each do |key, method|


The code uses instance_variable_get to access Reline's internal @key_bindings, which is a brittle approach that depends on internal implementation details. If Reline changes its internal structure in future versions, this code will break. Consider checking if Reline provides a public API for accessing keybindings, or add error handling for when the instance variable doesn't exist.

Suggested change

config.keymap.instance_variable_get(:@key_bindings).each do |key, method|

keymap = config.keymap

key_bindings =

if keymap.respond_to?(:key_bindings)

keymap.key_bindings

elsif keymap.instance_variable_defined?(:@key_bindings)

keymap.instance_variable_get(:@key_bindings)

else

{}

end

key_bindings.each do |key, method|

Copilot · 2026-01-17T13:05:01Z

+        when "\e[F", "\eOF" then 'End'
+        when "\e[H", "\eOH" then 'Home'
+        when "\e[1~", "\e[7~" then 'Home' # rubocop:disable Lint/DuplicateBranch
+        when "\e[4~", "\e[8~" then 'End' # rubocop:disable Lint/DuplicateBranch


The rubocop:disable comments for Lint/DuplicateBranch on lines 42 and 43 are suppressing legitimate warnings. These case branches do have duplicate 'Home' and 'End' return values. The duplicate branches could be combined (e.g., when "\e[F", "\eOF", "\e[4~", "\e[8~" then 'End') to eliminate the need for these suppressions and improve maintainability.

Suggested change

when "\e[F", "\eOF" then 'End'

when "\e[H", "\eOH" then 'Home'

when "\e[1~", "\e[7~" then 'Home' # rubocop:disable Lint/DuplicateBranch

when "\e[4~", "\e[8~" then 'End' # rubocop:disable Lint/DuplicateBranch

when "\e[F", "\eOF", "\e[4~", "\e[8~" then 'End'

when "\e[H", "\eOH", "\e[1~", "\e[7~" then 'Home'

Copilot · 2026-01-17T13:05:02Z

+  end
+end
+
+# IRB が読み込まれている場合のみ登録


The comment on line 24 is in Japanese while all other code and comments in the file are in English. For consistency and to ensure all team members can understand the codebase, comments should be written in English.

Suggested change

# IRB が読み込まれている場合のみ登録

# Register only if IRB has been loaded

Add introspection utilities for Reline keybindings and IRB command to…

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… display them

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Copilot started reviewing on behalf of Syati January 17, 2026 13:02 View session

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Base automatically changed from custom_package to main January 19, 2026 13:01

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Add introspection utilities for Reline keybindings and IRB command to…#4

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		# Load commands only if IRB is available
		require_relative 'reline_pac/irb_commands' if defined?(IRB)

	max_key_length = bindings.keys.map(&:length).max
	max_key_length = bindings.keys.map(&:length).max \|\| 0

-        config.keymap.instance_variable_get(:@key_bindings).each do |key, method|
+        keymap = config.keymap
+        key_bindings =
+          if keymap.respond_to?(:key_bindings)
+            keymap.key_bindings
+          elsif keymap.instance_variable_defined?(:@key_bindings)
+            keymap.instance_variable_get(:@key_bindings)
+          else
+            {}
+          end
+        key_bindings.each do |key, method|

	# IRB が読み込まれている場合のみ登録
	# Register only if IRB has been loaded

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Pull request overview

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