Merge branch 'blog-ltest-opam' into 'master'

[blog] post about LTest opam release

See merge request !148

_posts/2022-04-19-ltest-plugins-released.md

+---
+layout: post
+author: André Maroneze (review by Virgile Prevosto)
+date: 2022-04-19 12:00 +0100
+categories: test
+title: "Test plug-ins (re-)released: LUncov, LAnnotate, LReplay (all part of LTest)"
+---
+
+The Ltest "meta-plugin" (composed of three parts: LUncov, LAnnotate and LReplay)
+has been (re-)released on
+[Frama-C's public Gitlab](https://git.frama-c.com/pub/ltest),
+and as 3 opam packages:
+[frama-c-luncov](https://opam.ocaml.org/packages/frama-c-luncov/),
+[frama-c-lannotate](https://opam.ocaml.org/packages/frama-c-lannotate/),
+and [lreplay](https://opam.ocaml.org/packages/lreplay/).
+
+These plugins help measure test coverage based on *hyperlabels*.
+Details about them are published
+[here](http://sebastien.bardin.free.fr/final-SCP-2021.pdf) and
+[here](http://sebastien.bardin.free.fr/2017-icst-tool.pdf)
+(you can also see the
+[LTest plugin page on the Frama-C website](https://www.frama-c.com/fc-plugins/ltest.html)).
+
+Note that these plugins do not help generating test cases;
+for that, you may want to use
+[PathCrawler](https://www.frama-c.com/fc-plugins/pathcrawler.html)
+(not open-source).
+
+## A bit of history
+
+The LTest plugin is not new: it
+[has been released several years ago](https://micdel.fr/ltest.html),
+as part of Mickaël Delahaye's PhD. However, that version (compatible with
+a patched version of Frama-C Neon) has aged a bit, making it hard for users
+to get it working with recent Frama-C versions. Other releases were made
+on [Github](https://github.com/ltest-dev/LTest), usually related to published
+papers, but once again, their maintenance was sporadic.
+This opam release, plus the code being kept closer to Frama-C's development
+version in Gitlab, should help keep these plug-ins relevant. Note that the
+released version is numbered 0.1, which indicates that they are still in an
+experimental stage; industrial users should contact the Frama-C team for
+details about their maturity.
+
+You may also have noticed: why is the opam package for LReplay named
+`lreplay` and not `frama-c-lreplay`? The simple reason is that, unlike the
+others, it is not a Frama-C plug-in *per se*, but an independent tool
+(it even has its own Dune build file) that can be used with or without
+Frama-C. It turns out that its defaults are mostly tuned for using it in
+conjunction with
+[PathCrawler](https://www.frama-c.com/fc-plugins/pathcrawler.html),
+but it can be configured for use with other test generators.