instance method match

Ruby on Rails 3.0.20

Last seen in v4.1.16

Available in: v2.2.3 v2.3.18 v3.0.20 v3.1.12 v3.2.22.5 v4.0.13 v4.1.16

Signature

match(element, first?) => array or nil

Matches an element against the selector.

For a simple selector this method returns an array with the element if the element matches, nil otherwise.

For a complex selector (sibling and descendant) this method returns an array with all matching elements, nil if no match is found.

Use +first_only=true+ if you are only interested in the first element.

For example:

if selector.match(element)
  puts "Element is a login form"
end

Parameters

element req
first_only opt = false
Source
# File actionpack/lib/action_controller/vendor/html-scanner/html/selector.rb, line 363
    def match(element, first_only = false)
      # Match element if no element name or element name same as element name
      if matched = (!@tag_name || @tag_name == element.name)
        # No match if one of the attribute matches failed
        for attr in @attributes
          if element.attributes[attr[0]] !~ attr[1]
            matched = false
            break
          end
        end
      end

      # Pseudo class matches (nth-child, empty, etc).
      if matched
        for pseudo in @pseudo
          unless pseudo.call(element)
            matched = false
            break
          end
        end
      end

      # Negation. Same rules as above, but we fail if a match is made.
      if matched && @negation
        for negation in @negation
          if negation[:tag_name] == element.name
            matched = false
          else
            for attr in negation[:attributes]
              if element.attributes[attr[0]] =~ attr[1]
                matched = false
                break
              end
            end
          end
          if matched
            for pseudo in negation[:pseudo]
              if pseudo.call(element)
                matched = false
                break
              end
            end
          end
          break unless matched
        end
      end

      # If element matched but depends on another element (child,
      # sibling, etc), apply the dependent matches instead.
      if matched && @depends
        matches = @depends.call(element, first_only)
      else
        matches = matched ? [element] : nil
      end

      # If this selector is part of the group, try all the alternative
      # selectors (unless first_only).
      if !first_only || !matches
        @alternates.each do |alternate|
          break if matches && first_only
          if subset = alternate.match(element, first_only)
            if matches
              matches.concat subset
            else
              matches = subset
            end
          end
        end
      end

      matches
    end

Defined in actionpack/lib/action_controller/vendor/html-scanner/html/selector.rb line 363 · View on GitHub · Improve this page · Find usages on GitHub

Defined in HTML::Selector

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