Children of xsl:comment are traced differently depending on
the order of `<node>` elements in XSLT; without xspec#1918 change,
the xsl:value-of child is incorrectly marked as missed.

Mimics the difference that the Java change in xspec#1918 makes
in test/global-override.xspec.

The overridden global xsl:param is marked as ignored, but an
open design question is whether it should instead be marked
as missed. The comment in this revision says "Expected miss"
in anticipation of changing the treatment of global params.

…#1932)

* Coverage tests from birdya22 ZIP-file

Tests written by user birdya22 (Adrian Bird).
From https://github.com/xspec/xspec/files/15447320/20240526Update.zip

* Conventions, Markdown based on .txt from birdya22

In the ZIP-file from user birdya22 (Adrian Bird) is a readme.txt
file that, among other things, documents some conventions used in
the per-element coverage tests. This Markdown file is based on that
documentation.

* Generated expected results

Using Saxon 12.4 and XSpec master branch as of 2 June 2024

* In xsl:apply-templates test, use mode attribute

* In xsl:assert test, remove try/catch and add -ea

1. xsl:try/xsl:catch structure has its own test, so simplify this test
by using catch="yes" in XSpec
2. Add Saxon custom option to enable assertions

* Remove unneeded namespace declaration

* In xsl:attribute test, add case for child element

Trace treats a child element and its text child differently
from a child text node, so both patterns are worth capturing.

* In xsl:global-context-item test, use XSpec context

In external transformations, XSpec passes x:context to
XSLT as the global context item, so XSLT can get it using
"." syntax. In external transformations, XSpec x:param
does not get passed to XSLT processor.

* Make xsl-accumulator-01.xspec run w/ external

run-as="external" requires an additional xsl:mode
element with use-accumulators, for the default mode.
This change facilitates importing xsl-accumulator-01.xspec
into a parent XSpec file that has run-as="external".

* Add to xsl:on-non-empty test

In case Saxon optimizes away a case where
static analysis of XSLT shows the sequence constructor
is always empty, provide a case that requires the
source document in addition to the XSLT.

* In xsl:comment test, add more cases

Children of xsl:comment are traced differently depending on
the order of `<node>` elements in XSLT; without #1918 change,
the xsl:value-of child is incorrectly marked as missed.

* Misc. non-substantive tweaks

Typos, comments, code formatting

* Example for xsl:evaluate with parameter

* In xsl:map test, add more cases

Trace behavior for xsl:variable is complicated, so judging
trace behavior of xsl:map and xsl:map-entry might be
easier with additional data points. Use a template parameter
and function body as additional contexts for xsl:map.

* In xsl:message test, add cases that terminate

* In xsl:mode test, add a case without name attribute

* In xsl:next-match test, include more cases

- Case with xsl:with-param child
- Case where the next match is built-in template

* In xsl:where-populated test, consistent structure

For testing, it shouldn't matter whether `<node type="where-populated">`
is the child or the parent of xsl:where-populated. This commit makes the
structure consistent between the two cases.

* In xsl:catch test, add more cases

Design document suggests an "unknown" status for xsl:catch
coverage reporting, which is used when xsl:catch has no children.
Include example of two no-children cases (select attribute and
empty) for executed xsl:catch and non-executed xsl:catch
situations.

* In xsl:with-param test, add xsl:evaluate case

* In xsl:param test, include global not overridden

Mimics the difference that the Java change in #1918 makes
in test/global-override.xspec.

The overridden global xsl:param is marked as ignored, but an
open design question is whether it should instead be marked
as missed. The comment in this revision says "Expected miss"
in anticipation of changing the treatment of global params.

* Fix lint issues

* Regenerate expected results

* Address review comments from birdya22

Also, regenerate the expected results corresponding to
the modified .xsl files.