XSpec in practice: testing an XSLT stylesheet
XSpec describes what a stylesheet must produce, in a separate XML file. The first useful test fits in fifteen lines.
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Debugging, testing and understanding XSLT — field notes, not theory.
Setting a breakpoint in an XSLT stylesheet
An XSLT breakpoint does not stop a line — it stops a node being processed by a template. That difference explains most breakpoints that never fire.