class RuboCop::Cop::Style::FormatString
This cop enforces the use of a single string formatting utility. Valid options include Kernel#format, Kernel#sprintf and String#%.
The detection of String#% cannot be implemented in a reliable manner for all cases, so only two scenarios are considered - if the first argument is a string literal and if the second argument is an array literal.
Public Instance Methods
on_send(node)
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# File lib/rubocop/cop/style/format_string.rb, line 16 def on_send(node) add_offense(node, :selector) if offending_node?(node) end
Private Instance Methods
format?(node)
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# File lib/rubocop/cop/style/format_string.rb, line 43 def format?(node) format_method?(:format, node) end
format_method?(name, node)
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# File lib/rubocop/cop/style/format_string.rb, line 33 def format_method?(name, node) receiver, method_name, *args = *node # commands have no explicit receiver return false unless !receiver && method_name == name # we do an argument count check to reduce false positives args.size >= 2 end
message(node)
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# File lib/rubocop/cop/style/format_string.rb, line 59 def message(node) _receiver_node, method_name, *_arg_nodes = *node preferred = if style == :percent 'String#%' else style end method_name = 'String#%' if method_name == :% "Favor `#{preferred}` over `#{method_name}`." end
offending_node?(node)
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# File lib/rubocop/cop/style/format_string.rb, line 22 def offending_node?(node) case style when :format sprintf?(node) || percent?(node) when :sprintf format?(node) || percent?(node) when :percent format?(node) || sprintf?(node) end end
percent?(node)
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# File lib/rubocop/cop/style/format_string.rb, line 51 def percent?(node) receiver_node, method_name, *arg_nodes = *node method_name == :% && ([:str, :dstr].include?(receiver_node.type) || arg_nodes[0].type == :array) end
sprintf?(node)
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# File lib/rubocop/cop/style/format_string.rb, line 47 def sprintf?(node) format_method?(:sprintf, node) end