Module: Dommy::Internal::Namespaces

Defined in:
lib/dommy/internal/namespaces.rb

Overview

Namespace constants and the WHATWG DOM "validate and extract" algorithm, shared by createAttributeNS / setAttributeNS / createElementNS.

Constant Summary collapse

HTML = 
"http://www.w3.org/1999/xhtml"
SVG = 
"http://www.w3.org/2000/svg"
MATHML = 
"http://www.w3.org/1998/Math/MathML"
XML = 
"http://www.w3.org/XML/1998/namespace"
"http://www.w3.org/1999/xlink"
XMLNS = 
"http://www.w3.org/2000/xmlns/"
NC_START =

XML Name / QName productions, matching the canonical xml-name-validator package (what WHATWG DOM "validate" relies on). Built from the XML 1.0 NameStartChar / NameChar Unicode ranges; an NCName excludes ":", a QName is one optional prefix: + local NCName.

"A-Za-z_\\u00C0-\\u00D6\\u00D8-\\u00F6\\u00F8-\\u02FF\\u0370-\\u037D" \
"\\u037F-\\u1FFF\\u200C-\\u200D\\u2070-\\u218F\\u2C00-\\u2FEF" \
"\\u3001-\\uD7FF\\uF900-\\uFDCF\\uFDF0-\\uFFFD\\u{10000}-\\u{EFFFF}"
NC_EXTRA = 
"\\-.0-9\\u00B7\\u0300-\\u036F\\u203F-\\u2040"
NCSTART = 
"[#{NC_START}]"
NCCHAR = 
"[#{NC_START}#{NC_EXTRA}]"
NAME =

The full Name production (NameStartChar additionally includes ":").

Regexp.new("\\A[:#{NC_START}][:#{NC_START}#{NC_EXTRA}]*\\z")
HTML_NAME =

createElement / setAttribute name validation. Browsers (and the WPT tests that pin web reality) are far more lenient than the XML Name production: any non-empty string with no ASCII whitespace or ">", whose first character is not a digit, ".", "-", "<", ">", or "}". (Names like "f}oo", "f<oo" or a leading combining mark are valid here but not under the strict QName production the *AttributeNS family still uses.)

/\A(?![\s0-9.\-<>}])[^\s>]+\z/
QNAME =

PrefixedName | UnprefixedName.

Regexp.new(
  "(?:\\A#{NCSTART}#{NCCHAR}*:#{NCSTART}#{NCCHAR}*\\z)|(?:\\A#{NCSTART}#{NCCHAR}*\\z)"
)
LOCAL_FORBIDDEN =

Code points forbidden anywhere in a "valid local name" / "valid namespace prefix" per the modern WHATWG algorithm: ASCII whitespace (TAB, LF, FF, CR, SPACE), NULL, U+002F (/), U+003E (>).

Regexp.new("[\\u0000\\u0009\\u000A\\u000C\\u000D\\u0020/>]")
ELEMENT_LOCAL_START =

Valid first code point of an element local name: ASCII alpha, U+003A (:), U+005F (_), or any code point U+0080 and above.

Regexp.new("\\A[A-Za-z:_\\u0080-\\u{10FFFF}]")

Class Method Summary collapse

Class Method Details

.valid_element_local_name?(str) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/dommy/internal/namespaces.rb', line 54

def valid_element_local_name?(str)
  return false if str.empty?
  return false unless str.match?(ELEMENT_LOCAL_START)

  rest = str[1..]
  rest.nil? || rest.empty? || !rest.match?(LOCAL_FORBIDDEN)
end

.valid_namespace_prefix?(str) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/dommy/internal/namespaces.rb', line 50

def valid_namespace_prefix?(str)
  !str.empty? && !str.match?(LOCAL_FORBIDDEN)
end

.validate_and_extract(namespace, qualified_name, context: :attribute) ⇒ Object

https://dom.spec.whatwg.org/#validate-and-extract Returns [namespace_or_nil, prefix_or_nil, local_name]. Raises DOMException (InvalidCharacterError / NamespaceError) on bad input.

context: :element applies the modern WHATWG "validate" character rules (lenient: a restricted first code point then any non-forbidden code points, multiple colons allowed when namespaced). context: :attribute (the default) keeps the strict XML QName production used historically by the *AttributeNS family.



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# File 'lib/dommy/internal/namespaces.rb', line 71

def validate_and_extract(namespace, qualified_name, context: :attribute)
  ns = namespace.to_s
  ns = nil if ns.empty?
  qname = qualified_name.to_s

  prefix = nil
  local = qname
  if qname.include?(":")
    # Split on the FIRST colon: any further colons stay in the local part
    # (e.g. "f:o:o" → prefix "f", local "o:o").
    prefix, local = qname.split(":", 2)
  end

  if context == :element
    if prefix && !valid_namespace_prefix?(prefix)
      raise DOMException::InvalidCharacterError, "invalid namespace prefix: #{prefix.inspect}"
    end
    unless valid_element_local_name?(local)
      raise DOMException::InvalidCharacterError, "invalid local name: #{local.inspect}"
    end
  else
    unless qname.match?(QNAME)
      raise DOMException::InvalidCharacterError, "invalid qualified name: #{qname.inspect}"
    end
  end

  if prefix && ns.nil?
    raise DOMException::NamespaceError, "prefix #{prefix.inspect} with null namespace"
  end
  if prefix == "xml" && ns != XML
    raise DOMException::NamespaceError, "prefix 'xml' must use the XML namespace"
  end
  if (qname == "xmlns" || prefix == "xmlns") && ns != XMLNS
    raise DOMException::NamespaceError, "'xmlns' must use the XMLNS namespace"
  end
  if ns == XMLNS && qname != "xmlns" && prefix != "xmlns"
    raise DOMException::NamespaceError, "the XMLNS namespace requires the 'xmlns' name/prefix"
  end

  [ns, prefix, local]
end