[ruby/reline] Fix inputrc nested $if $else $endif bug

(https://github.com/ruby/reline/pull/689)

https://github.com/ruby/reline/commit/0d8aea26ec

lib/reline/config.rb

@@ -53,8 +53,6 @@ class Reline::Config
     @additional_key_bindings[:vi_insert] = {}
     @additional_key_bindings[:vi_command] = {}
     @oneshot_key_bindings = {}
-    @skip_section = nil
-    @if_stack = nil
     @editing_mode_label = :emacs
     @keymap_label = :emacs
     @keymap_prefix = []
@@ -190,9 +188,7 @@ class Reline::Config
         end
       end
     end
-    conditions = [@skip_section, @if_stack]
-    @skip_section = nil
-    @if_stack = []
+    if_stack = []
 
     lines.each_with_index do |line, no|
       next if line.match(/\A\s*#/)
@@ -201,11 +197,11 @@ class Reline::Config
 
       line = line.chomp.lstrip
       if line.start_with?('$')
-        handle_directive(line[1..-1], file, no)
+        handle_directive(line[1..-1], file, no, if_stack)
         next
       end
 
-      next if @skip_section
+      next if if_stack.any? { |_no, skip| skip }
 
       case line
       when /^set +([^ ]+) +([^ ]+)/i
@@ -219,14 +215,12 @@ class Reline::Config
         @additional_key_bindings[@keymap_label][@keymap_prefix + keystroke] = func
       end
     end
-    unless @if_stack.empty?
-      raise InvalidInputrc, "#{file}:#{@if_stack.last[1]}: unclosed if"
+    unless if_stack.empty?
+      raise InvalidInputrc, "#{file}:#{if_stack.last[0]}: unclosed if"
     end
-  ensure
-    @skip_section, @if_stack = conditions
   end
 
-  def handle_directive(directive, file, no)
+  def handle_directive(directive, file, no, if_stack)
     directive, args = directive.split(' ')
     case directive
     when 'if'
@@ -239,18 +233,17 @@ class Reline::Config
         condition = true if args == 'Ruby'
         condition = true if args == 'Reline'
       end
-      @if_stack << [file, no, @skip_section]
-      @skip_section = !condition
+      if_stack << [no, !condition]
     when 'else'
-      if @if_stack.empty?
+      if if_stack.empty?
         raise InvalidInputrc, "#{file}:#{no}: unmatched else"
       end
-      @skip_section = !@skip_section
+      if_stack.last[1] = !if_stack.last[1]
     when 'endif'
-      if @if_stack.empty?
+      if if_stack.empty?
         raise InvalidInputrc, "#{file}:#{no}: unmatched endif"
       end
-      @skip_section = @if_stack.pop
+      if_stack.pop
     when 'include'
       read(File.expand_path(args))
     end

test/reline/test_config.rb

@@ -216,6 +216,38 @@ class Reline::Config::Test < Reline::TestCase
     end
   end
 
+  def test_nested_if_else
+    @config.read_lines(<<~LINES.lines)
+      $if Ruby
+        "\x1": "O"
+        $if NotRuby
+          "\x2": "X"
+        $else
+          "\x3": "O"
+          $if Ruby
+            "\x4": "O"
+          $else
+            "\x5": "X"
+          $endif
+          "\x6": "O"
+        $endif
+        "\x7": "O"
+      $else
+        "\x8": "X"
+        $if NotRuby
+          "\x9": "X"
+        $else
+          "\xA": "X"
+        $endif
+        "\xB": "X"
+      $endif
+      "\xC": "O"
+    LINES
+    keys = [0x1, 0x3, 0x4, 0x6, 0x7, 0xC]
+    key_bindings = keys.to_h { |k| [[k.ord], ['O'.ord]] }
+    assert_equal(key_bindings, @config.instance_variable_get(:@additional_key_bindings)[:emacs])
+  end
+
   def test_unclosed_if
     e = assert_raise(Reline::Config::InvalidInputrc) do
       @config.read_lines(<<~LINES.lines, "INPUTRC")