class RuboCop::Cop::Style::SpecialGlobalVars
This cop looks for uses of Perl-style global variables. Correcting to global variables in the ‘English’ library will add a require statement to the top of the file if enabled by RequireEnglish config.
@safety
Autocorrection is marked as unsafe because if `RequireEnglish` is not true, replacing perl-style variables with english variables will break.
@example EnforcedStyle: use_english_names (default)
# good require 'English' # or this could be in another file. puts $LOAD_PATH puts $LOADED_FEATURES puts $PROGRAM_NAME puts $ERROR_INFO puts $ERROR_POSITION puts $FIELD_SEPARATOR # or $FS puts $OUTPUT_FIELD_SEPARATOR # or $OFS puts $INPUT_RECORD_SEPARATOR # or $RS puts $OUTPUT_RECORD_SEPARATOR # or $ORS puts $INPUT_LINE_NUMBER # or $NR puts $LAST_READ_LINE puts $DEFAULT_OUTPUT puts $DEFAULT_INPUT puts $PROCESS_ID # or $PID puts $CHILD_STATUS puts $LAST_MATCH_INFO puts $IGNORECASE puts $ARGV # or ARGV
@example EnforcedStyle: use_perl_names
# good puts $: puts $" puts $0 puts $! puts $@ puts $; puts $, puts $/ puts $\ puts $. puts $_ puts $> puts $< puts $$ puts $? puts $~ puts $= puts $*
@example EnforcedStyle: use_builtin_english_names
Like ‘use_perl_names` but allows builtin global vars.
# good puts $LOAD_PATH puts $LOADED_FEATURES puts $PROGRAM_NAME puts ARGV puts $: puts $" puts $0 puts $! puts $@ puts $; puts $, puts $/ puts $\ puts $. puts $_ puts $> puts $< puts $$ puts $? puts $~ puts $= puts $*
Constants
- BUILTIN_VARS
- ENGLISH_VARS
- LIBRARY_NAME
- MSG_BOTH
- MSG_ENGLISH
- MSG_REGULAR
- NON_ENGLISH_VARS
Anything not in this set is provided by the English library.
- PERL_VARS
- STYLE_VARS_MAP
Public Instance Methods
autocorrect(corrector, node, global_var)
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# File lib/rubocop/cop/style/special_global_vars.rb, line 177 def autocorrect(corrector, node, global_var) node = node.parent while node.parent&.begin_type? && node.parent.children.one? if should_require_english?(global_var) ensure_required(corrector, node, LIBRARY_NAME) @required_english = true end corrector.replace(node, replacement(node, global_var)) end
message(global_var)
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# File lib/rubocop/cop/style/special_global_vars.rb, line 169 def message(global_var) if style == :use_english_names format_english_message(global_var) else format(MSG_REGULAR, prefer: preferred_names(global_var).first, global: global_var) end end
on_gvar(node)
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# File lib/rubocop/cop/style/special_global_vars.rb, line 153 def on_gvar(node) global_var, = *node return unless (preferred = preferred_names(global_var)) if preferred.include?(global_var) correct_style_detected else style_detected(matching_styles(global_var)) add_offense(node, message: message(global_var)) do |corrector| autocorrect(corrector, node, global_var) end end end
on_new_investigation()
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Calls superclass method
RuboCop::Cop::RequireLibrary#on_new_investigation
# File lib/rubocop/cop/style/special_global_vars.rb, line 148 def on_new_investigation super @required_english = false end
Private Instance Methods
add_require_english?()
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# File lib/rubocop/cop/style/special_global_vars.rb, line 248 def add_require_english? cop_config['RequireEnglish'] end
english_name_replacement(preferred_name, node)
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# File lib/rubocop/cop/style/special_global_vars.rb, line 242 def english_name_replacement(preferred_name, node) return "\#{#{preferred_name}}" if node.begin_type? "{#{preferred_name}}" end
format_english_message(global_var)
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# File lib/rubocop/cop/style/special_global_vars.rb, line 191 def format_english_message(global_var) regular, english = ENGLISH_VARS[global_var].partition do |var| NON_ENGLISH_VARS.include? var end format_message(english, regular, global_var) end
format_list(items)
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For
now, we assume that lists are 2 items or less. Easy grammar!
# File lib/rubocop/cop/style/special_global_vars.rb, line 213 def format_list(items) items.join('` or `') end
format_message(english, regular, global)
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# File lib/rubocop/cop/style/special_global_vars.rb, line 199 def format_message(english, regular, global) if regular.empty? format(MSG_ENGLISH, prefer: format_list(english), global: global) elsif english.empty? format(MSG_REGULAR, prefer: format_list(regular), global: global) else format(MSG_BOTH, prefer: format_list(english), regular: format_list(regular), global: global) end end
matching_styles(global)
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# File lib/rubocop/cop/style/special_global_vars.rb, line 236 def matching_styles(global) STYLE_VARS_MAP.map do |style, vars| style if vars.values.flatten(1).include? global end.compact end
preferred_names(global)
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# File lib/rubocop/cop/style/special_global_vars.rb, line 228 def preferred_names(global) vars = STYLE_VARS_MAP.fetch(style) do raise ArgumentError, "Invalid style: #{style.inspect}" end vars[global] end
replacement(node, global_var)
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# File lib/rubocop/cop/style/special_global_vars.rb, line 217 def replacement(node, global_var) parent_type = node.parent&.type preferred_name = preferred_names(global_var).first return preferred_name.to_s unless %i[dstr xstr regexp].include?(parent_type) return english_name_replacement(preferred_name, node) if style == :use_english_names "##{preferred_name}" end
should_require_english?(global_var)
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# File lib/rubocop/cop/style/special_global_vars.rb, line 252 def should_require_english?(global_var) style == :use_english_names && add_require_english? && !@required_english && !NON_ENGLISH_VARS.include?(preferred_names(global_var).first) end