xsl:sort's default text order treats spaces as ignorable at the
primary level with a later-first-space tie-break, the Java Collator
semantics the conformance golds encode, derived from the gold
orderings. Xalan baseline 129 -> 128.
The XSLT layer's id() follows the XPath definition exactly: only
attributes the source's DTD declares as type ID identify elements
(internal or external subset, via the transform's resolver), and a
document without ID declarations yields the empty set. generate-id()
produces non-empty, distinct identifiers for attribute and namespace
nodes through their identity hash. Lookup implementations move to
XSLTLookups.swift for the file caps. Xalan baseline 131 -> 129.
Same-name xsl:attribute-set declarations merge as ordered definitions
per 7.1.4, each expanding its used sets before its own attributes with
later definitions winning; xsl:copy carries the source element's
in-scope namespace nodes per 7.5; the namespace fixup lets a carried
attribute prefix shadow an inherited binding unless the element's own
name relies on it; the html method minimizes boolean attributes whose
value repeats their name; and external DTDs and entities in the
stylesheet or source resolve through the transform's document loader.
Four unit tests pin the behaviors. Xalan baseline 174 -> 159
(attribset 13 -> 4, copy 12 -> 7).
format-number of a value at or beyond 2^53 ran an unguarded
Double-to-Int conversion, a fatal trap reachable from user data; a
fraction picture beyond 15 places overflowed the scale conversion the
same way; and xsl:number value= beyond 2^53 trapped identically.
Digit extraction clamps fraction places to 15 (the 2^53 exactness
bound), pads back to the picture's minimum, renders out-of-range
integers through the exponent expander, and xsl:number falls back to
plain number rendering outside [1, 2^53). Sort-key rows always carry
one key per sort. Regression tests cover all three trap paths.
key() resolves its index against the current node's own document,
built lazily per document root, so keys work inside document() trees;
a node-set use expression indexes the matched node under every
member's string value; and key() results return in document order
regardless of lookup value order. Xalan baseline 187 -> 182.
Sort keys evaluate once per node with the node's own position, size,
variables, and bindings, so position()-based keys work, and NaN keys
order before numbers under data-type=number. Match patterns evaluate
over the matched node's own document, so templates match nodes loaded
through document(); the match cache keys include the document
identity. Xalan baseline 204 -> 187 (sort 18 -> 11, mdocs 14 -> 6).
apply-templates and for-each keep attribute and namespace nodes in
their selections; the context carries the non-tree current node with
its owner element backing the tree-only machinery, XPath evaluation
and current() start from it, match patterns select attribute nodes
through attribute identities in the match cache, the built-in rules
copy an attribute's or namespace's value as text, xsl:copy copies the
focused attribute or declaration itself, and an attribute result
arriving after element content is ignored (the XSLT recovery).
Sorting, for-each, and choose move to XSLTSorting.swift for the file
caps. Xalan baseline 352 -> 292 (axes 35 -> 16, copy 29 -> 16).
