FindLibXslt: Add LibXslt_VERSION

This deprecates the LIBXSLT_VERSION_STRING result variable.

Issue: #27088

Help/release/dev/find-modules.rst

@@ -19,6 +19,9 @@ Find Modules
 * The :module:`FindLibXml2` module now provides a ``LibXml2_VERSION`` result
   variable.  The ``LIBXML2_VERSION_STRING`` result variable is deprecated.
 
+* The :module:`FindLibXslt` module now provides a ``LibXslt_VERSION`` result
+  variable.  The ``LIBXSLT_VERSION_STRING`` result variable is deprecated.
+
 * The :module:`FindPostgreSQL` module now provides a ``PostgreSQL_VERSION``
   result variable.  The ``PostgreSQL_VERSION_STRING`` result variable is
   deprecated.

Modules/FindLibXslt.cmake

@@ -6,7 +6,11 @@ FindLibXslt
 -----------
 
 Finds the XSL Transformations, Extensible Stylesheet Language Transformations
-(XSLT) library (libxslt).
+(XSLT) library (libxslt):
+
+.. code-block:: cmake
+
+  find_package(LibXslt [<version>] [...])
 
 Imported Targets
 ^^^^^^^^^^^^^^^^
@@ -36,8 +40,14 @@ Result Variables
 This module sets the following variables:
 
 ``LibXslt_FOUND``
-  Boolean indicating whether the libxslt is found.  For backward compatibility,
-  the ``LIBXSLT_FOUND`` variable is also set to the same value.
+  Boolean indicating whether (the requested version of) libxslt is found.
+  For backward compatibility, the ``LIBXSLT_FOUND`` variable is also set to
+  the same value.
+
+``LibXslt_VERSION``
+  .. versionadded:: 4.2
+
+  The version of libxslt found.
 
 ``LIBXSLT_LIBRARIES``
   Libraries needed to link to libxslt.
@@ -45,9 +55,6 @@ This module sets the following variables:
 ``LIBXSLT_DEFINITIONS``
   Compiler switches required for using libxslt.
 
-``LIBXSLT_VERSION_STRING``
-  Version of libxslt found.
-
 ``LIBXSLT_EXSLT_LIBRARIES``
   Libraries needed when linking against the exslt library.  These are available
   and needed only when using exslt library.
@@ -70,6 +77,17 @@ The following cache variables may also be set:
   Full path to the XSLT processor executable ``xsltproc`` if found.  This path
   is optional.
 
+Deprecated Variables
+^^^^^^^^^^^^^^^^^^^^
+
+The following variables are provided for backward compatibility:
+
+``LIBXSLT_VERSION_STRING``
+  .. deprecated:: 4.2
+    Superseded by the ``LibXslt_VERSION``.
+
+  The version of libxslt found.
+
 Examples
 ^^^^^^^^
 
@@ -159,20 +177,22 @@ set(LIBXSLT_EXSLT_LIBRARIES ${LIBXSLT_EXSLT_LIBRARY} )
 find_program(LIBXSLT_XSLTPROC_EXECUTABLE xsltproc)
 
 if(PC_LIBXSLT_VERSION)
-    set(LIBXSLT_VERSION_STRING ${PC_LIBXSLT_VERSION})
+    set(LibXslt_VERSION ${PC_LIBXSLT_VERSION})
+    set(LIBXSLT_VERSION_STRING "${LibXslt_VERSION}")
 elseif(LIBXSLT_INCLUDE_DIR AND EXISTS "${LIBXSLT_INCLUDE_DIR}/libxslt/xsltconfig.h")
     file(STRINGS "${LIBXSLT_INCLUDE_DIR}/libxslt/xsltconfig.h" libxslt_version_str
          REGEX "^#define[\t ]+LIBXSLT_DOTTED_VERSION[\t ]+\".*\"")
 
     string(REGEX REPLACE "^#define[\t ]+LIBXSLT_DOTTED_VERSION[\t ]+\"([^\"]*)\".*" "\\1"
-           LIBXSLT_VERSION_STRING "${libxslt_version_str}")
+           LibXslt_VERSION "${libxslt_version_str}")
+    set(LIBXSLT_VERSION_STRING "${LibXslt_VERSION}")
     unset(libxslt_version_str)
 endif()
 
 include(FindPackageHandleStandardArgs)
 find_package_handle_standard_args(LibXslt
                                   REQUIRED_VARS LIBXSLT_LIBRARIES LIBXSLT_INCLUDE_DIR
-                                  VERSION_VAR LIBXSLT_VERSION_STRING)
+                                  VERSION_VAR LibXslt_VERSION)
 
 mark_as_advanced(LIBXSLT_INCLUDE_DIR
                  LIBXSLT_LIBRARY

Tests/CMakeOnly/AllFindModules/CMakeLists.txt

@@ -120,7 +120,7 @@ foreach(
     GIF GTK2
     HDF5
     Jasper JPEG
-    LibArchive LIBLZMA LibXml2
+    LibArchive LIBLZMA LibXml2 LibXslt
     OPENSCENEGRAPH
     PostgreSQL Protobuf
     Ruby RUBY

Tests/FindLibXslt/Test/CMakeLists.txt

@@ -6,7 +6,7 @@ find_package(Iconv)
 find_package(LibXml2 REQUIRED)
 find_package(LibXslt REQUIRED)
 
-add_definitions(-DCMAKE_EXPECTED_LibXslt_VERSION="${LIBXSLT_VERSION_STRING}")
+add_definitions(-DCMAKE_EXPECTED_LibXslt_VERSION="${LibXslt_VERSION}")
 
 add_executable(libxslt_tgt libxslt.c)
 if(Iconv_FOUND)