XHTML Family User Agent Conformance Testable Assertions

Assertion Test Quote/Description
xhtml_conform-1 xhtml_conform-BF-01.htm In order to be consistent with the XML 1.0 Recommendation [XML], the user agent must parse and evaluate an XHTML document for well-formedness.
xhtml_conform-2 All mandatory features tested by individual test cases. When the user agent claims to support facilities defined within this specification or required by this specification through normative reference, it must do so in ways consistent with the facilities' definition.
xhtml_conform-3 Optional: not tested. When a user agent processes an XHTML document as generic [XML], it shall only recognize attributes of type ID (e.g., the id attribute on most XHTML elements) as fragment identifiers.
xhtml_conform-4 xhtml_conform-ER-01.htm If a user agent encounters an element it does not recognize, it must continue to process the children of that element. If the content is text, the text must be presented to the user.
xhtml_conform-5 xhtml_conform-ER-02.htm If a user agent encounters an attribute it does not recognize, it must ignore the entire attribute specification (i.e., the attribute and its value).
xhtml_conform-6 xhtml_conform-ER-03.htm If a user agent encounters an attribute value it doesn't recognize, it must use the default attribute value.
xhtml_conform-7 xhtml_conform-ER-04.htm If it encounters an entity reference (other than one of the predefined entities) ... the entity reference should be rendered as the characters (starting with the ampersand and ending with the semi-colon) that make up the entity reference.
xhtml_conform-8 xhtml_conform-BF-02.htm When rendering content, user agents that encounter characters or character entity references that are recognized but not renderable should display the document in such a way that it is obvious to the user that normal rendering has not taken place.
xhtml_conform-9 xhtml_conform-BF-03.htm All white space surrounding block elements should be removed.
xhtml_conform-10 xhtml_conform-BF-04.htm Comments are removed entirely and do not affect white space handling. One white space character on either side of a comment is treated as two white space characters.
xhtml_conform-11 Optional: not tested. When the 'xml:space' attribute is set to 'preserve', then) white space characters should be preserved and consequently LINE FEED characters within a block should not be converted.
xhtml_conform-12 xhtml_conform-BF-05.htm (When the 'xml:space' attribute is not set to 'preserve', then) Leading and trailing white space inside a block element must be removed.
xhtml_conform-13 xhtml_conform-BF-05.htm (When the 'xml:space' attribute is not set to 'preserve', then) LINE FEED characters must be converted into one of the following characters: a SPACE character, a ZERO WIDTH SPACE character (​), or no character (i.e. removed).
xhtml_conform-14 xhtml_conform-BF-05.htm (When the 'xml:space' attribute is not set to 'preserve', then) A sequence of white space characters without any LINE FEED characters must be reduced to a single SPACE character.
xhtml_conform-15 xhtml_conform-BF-05.htm (When the 'xml:space' attribute is not set to 'preserve', then) A sequence of white space characters with one or more LINE FEED characters must be reduced in the same way as a single LINE FEED character.
xhtml_conform-16 xhtml_conform-BF-06.htm
White space in attribute values is processed according to [XML].
Element Attribute NMTOKENS CDATA
  1. All line breaks must have been normalized on input to #xA as described in 2.11 End-of-Line Handling , so the rest of this algorithm operates on text normalized in this way.

  2. Begin with a normalized value consisting of the empty string.

  3. For each character, entity reference, or character reference in the unnormalized attribute value, beginning with the first and continuing to the last, do the following:

    • For a character reference, append the referenced character to the normalized value.

    • For an entity reference, recursively apply step 3 of this algorithm to the replacement text of the entity.

    • For a white space character (#x20, #xD, #xA, #x9), append a space character (#x20) to the normalized value.

    • For another character, append the character to the normalized value.

If the attribute type is not CDATA, then the XML processor must further process the normalized attribute value by discarding any leading and trailing space (#x20) characters, and by replacing sequences of space (#x20) characters by a single space (#x20) character.

Core class X
Core style X
html xmlns X
input value X
select size X
textarea cols X
textarea rows X
td,th colspan X
td,th rowspan X
img height X
img src X
img width X
img alt X
object codebase X
object data X
object height X
object width X
style media X
link charset X
link href X
link media X
base href X

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