Subject: Re: [xsl] How do you prove that your XSLT programs are correct? From: "Eliot Kimber eliot.kimber@xxxxxxxxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> Date: Fri, 15 Apr 2022 14:38:55 -0000 |
One of the practical challenges in testing the output of XSLTs is the sheer cost of maintaining the test cases themselves: if youre using some kind of diff-based checker (this is something we used for the GAO HTML publishing system using a home-grown XML diff mechanism) then you have to maintain the exemplars youre testing against, which can be a significant time cost. In general Ive found it more practical to depend on output inspection using both artificial test case documents where the content says what the correct expected result is as well as realistic content. This puts the time cost in the inspection and depends on the knowledge of the inspectors but tends to be a lower time cost overall. This is usually in the context of relatively low-budget projects or projects where absolute correctness is not a top concern (i.e., not safety critical or in a regulated industry). Testing PDF output is even more of a challengeAntenna House sells a PDF comparator tool that appears to do what you need (Ive never actually used the product) but you face the same exemplar maintenance challenge as for XML or HTML outputs. Cheers, E. _____________________________________________ Eliot Kimber Sr Staff Content Engineer O: 512 554 9368 M: 512 554 9368 servicenow.com<https://www.servicenow.com> LinkedIn<https://www.linkedin.com/company/servicenow> | Twitter<https://twitter.com/servicenow> | YouTube<https://www.youtube.com/user/servicenowinc> | Facebook<https://www.facebook.com/servicenow> From: Wendell Piez wapiez@xxxxxxxxxxxxxxx <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> Date: Friday, April 15, 2022 at 8:46 AM To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx <xsl-list@xxxxxxxxxxxxxxxxxxxxxx> Subject: Re: [xsl] How do you prove that your XSLT programs are correct? [External Email] Hi, What's more, Mike doesn't even touch on the question of defining what is correct, or for that matter how one of XSLT's great strengths is in its capability to handle things that are incorrect by one definition while correct by another. But yes, unit testing. It is not only the only way to know, it is the only way to know you really know. Cheers, Wendell On Thu, Apr 14, 2022 at 12:52 PM Michael Kay mike@xxxxxxxxxxxx<mailto:mike@xxxxxxxxxxxx> <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx<mailto:xsl-list-service@xxxxxxxxxxxx rytech.com>> wrote: You're not talking about proving correctness here, you're talking about testing. If you want to prove properties of the stylesheet statically, for example that the output will conform to a particular schema, then consider writing schema-aware XSLT code. (However, I'm very reluctant to talk about proviing "correctness". You can prove a hypothesis about the behaviour, but you can't prove that such behaviour will be considered "correct" in the real world.) For testing, XSpec is a popular framework, which roughly does what you describe in (2). This is also how the W3C XSLT test suite at https://github.com/w3c/xslt30-test<https://urldefense.com/v3/__https:/github. com/w3c/xslt30-test__;!!N4vogdjhuJM!EGPurchrCkklwpQF6l9me3Je_xTvv1dU3Y_XP0Dwh WgF2vKxLOw6cg3DXHTq7eRdXAW-pkoiBlgSSc1ghRE7PKIXjqC6SSQwc1R1GX88uKI$> works. (That test suite, of course, is geared more to coverage of constructs in the XSLT language, so the details will be rather different from tests of a user stylesheet, but the principle is much the same.) The biggest weakness I see in the way most users test their stylesheets is that they use far too few different source documents to achieve good coverage of the logic, especially the error cases. Michael Kay Saxonica > On 14 Apr 2022, at 17:08, Roger L Costello costello@xxxxxxxxx<mailto:costello@xxxxxxxxx> <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx<mailto:xsl-list-service@xxxxxxxxxxxx rytech.com>> wrote: > > Hi Folks, > > Scenario: You write an XSLT program that takes some input and outputs XML. You want to be sure that your XSLT program is correct. > > As I see it, there are two ways to help ensure the correctness of an XSLT program : > > 1. Pepper the XSLT program with assert statements, using xsl:assert. > > 2. Create a second XSLT program that queries the XML that was generated by the first XSLT program. This second XSLT program contains a series of XPath expressions to check various parts of the XML. > > Which of those do you use? Or do you use both? Or do you use something else? > > How do you ensure the correctness of your XSLT programs? > > /Roger > > -- ...Wendell Piez... ...wendell -at- nist -dot- gov... ...wendellpiez.com... ...pellucidliterature.org... ...pausepress.org... ...github.com/wendellpiez.<https://urldefense.com/v3/__http:/github.com/wende llpiez.__;!!N4vogdjhuJM!EGPurchrCkklwpQF6l9me3Je_xTvv1dU3Y_XP0DwhWgF2vKxLOw6c g3DXHTq7eRdXAW-pkoiBlgSSc1ghRE7PKIXjqC6SSQwc1R14Qb9XXQ$>.. ...gitlab.coko.foundation/wendell... XSL-List info and archive<https://urldefense.com/v3/__http:/www.mulberrytech.com/xsl/xsl-list__ ;!!N4vogdjhuJM!EGPurchrCkklwpQF6l9me3Je_xTvv1dU3Y_XP0DwhWgF2vKxLOw6cg3DXHTq7e RdXAW-pkoiBlgSSc1ghRE7PKIXjqC6SSQwc1R12QKqii8$> EasyUnsubscribe<https://urldefense.com/v3/__http:/lists.mulberrytech.com/unsu b/xsl-list/3453418__;!!N4vogdjhuJM!EGPurchrCkklwpQF6l9me3Je_xTvv1dU3Y_XP0DwhW gF2vKxLOw6cg3DXHTq7eRdXAW-pkoiBlgSSc1ghRE7PKIXjqC6SSQwc1R1RIqInF0$> (by email<>)
Current Thread |
---|
|
<- Previous | Index | Next -> |
---|---|---|
Re: [xsl] How do you prove that you, Wendell Piez wapiez@ | Thread | Re: [xsl] How do you prove that you, G. Ken Holman g.ken. |
Re: [xsl] How do you prove that you, Wendell Piez wapiez@ | Date | Re: [xsl] How do you prove that you, G. Ken Holman g.ken. |
Month |