find_package: Extend search path for combined Windows/UNIX convention

Find packages that install their cmake package configuration files in
`lib/cmake/<name>` when they are installed in the default Windows
CMAKE_INSTALL_PREFIX, `C:/Program Files/<name>`.

Closes: #16212

Help/command/find_package.rst

@@ -201,6 +201,9 @@ Each entry is meant for installation trees following Windows (W), UNIX
   <prefix>/(lib/<arch>|lib|share)/cmake/<name>*/                  (U)
   <prefix>/(lib/<arch>|lib|share)/<name>*/                        (U)
   <prefix>/(lib/<arch>|lib|share)/<name>*/(cmake|CMake)/          (U)
+  <prefix>/<name>*/(lib/<arch>|lib|share)/cmake/<name>*/          (W/U)
+  <prefix>/<name>*/(lib/<arch>|lib|share)/<name>*/                (W/U)
+  <prefix>/<name>*/(lib/<arch>|lib|share)/<name>*/(cmake|CMake)/  (W/U)
 
 On systems supporting OS X Frameworks and Application Bundles the
 following directories are searched for frameworks or bundles

Source/cmFindPackageCommand.cxx

@@ -1961,6 +1961,44 @@ bool cmFindPackageCommand::SearchPrefix(std::string const& prefix_in)
     }
   }
 
+  // PREFIX/(Foo|foo|FOO).*/(lib/ARCH|lib|share)/cmake/(Foo|foo|FOO).*/
+  {
+    cmFindPackageFileList lister(this);
+    lister / cmFileListGeneratorFixed(prefix) /
+      cmFileListGeneratorProject(this->Names) /
+      cmFileListGeneratorEnumerate(common) /
+      cmFileListGeneratorFixed("cmake") /
+      cmFileListGeneratorProject(this->Names);
+    if (lister.Search()) {
+      return true;
+    }
+  }
+
+  // PREFIX/(Foo|foo|FOO).*/(lib/ARCH|lib|share)/(Foo|foo|FOO).*/
+  {
+    cmFindPackageFileList lister(this);
+    lister / cmFileListGeneratorFixed(prefix) /
+      cmFileListGeneratorProject(this->Names) /
+      cmFileListGeneratorEnumerate(common) /
+      cmFileListGeneratorProject(this->Names);
+    if (lister.Search()) {
+      return true;
+    }
+  }
+
+  // PREFIX/(Foo|foo|FOO).*/(lib/ARCH|lib|share)/(Foo|foo|FOO).*/(cmake|CMake)/
+  {
+    cmFindPackageFileList lister(this);
+    lister / cmFileListGeneratorFixed(prefix) /
+      cmFileListGeneratorProject(this->Names) /
+      cmFileListGeneratorEnumerate(common) /
+      cmFileListGeneratorProject(this->Names) /
+      cmFileListGeneratorCaseInsensitive("cmake");
+    if (lister.Search()) {
+      return true;
+    }
+  }
+
   return false;
 }
 

Tests/FindPackageTest/Baz 1.3/lib/cmake/Baz/BazConfig.cmake

@@ -0,0 +1 @@
+# Test config file.

Tests/FindPackageTest/Baz 1.3/lib/cmake/Baz/BazConfigVersion.cmake

@@ -0,0 +1,7 @@
+set(PACKAGE_VERSION 1.3)
+if("${PACKAGE_FIND_VERSION_MAJOR}" EQUAL 1)
+  set(PACKAGE_VERSION_COMPATIBLE 1)
+  if("${PACKAGE_FIND_VERSION_MINOR}" EQUAL 3)
+    set(PACKAGE_VERSION_EXACT 1)
+  endif()
+endif()

Tests/FindPackageTest/Baz 2.0/share/Baz 2/BazConfig.cmake

@@ -0,0 +1 @@
+# Test config file.

Tests/FindPackageTest/Baz 2.0/share/Baz 2/BazConfigVersion.cmake

@@ -0,0 +1,7 @@
+set(PACKAGE_VERSION 2.0)
+if("${PACKAGE_FIND_VERSION_MAJOR}" EQUAL 2)
+  set(PACKAGE_VERSION_COMPATIBLE 1)
+  if("${PACKAGE_FIND_VERSION_MINOR}" EQUAL 0)
+    set(PACKAGE_VERSION_EXACT 1)
+  endif()
+endif()

Tests/FindPackageTest/Baz 2.1/lib/Baz 2/cmake/BazConfig.cmake

@@ -0,0 +1 @@
+# Test config file.

Tests/FindPackageTest/Baz 2.1/lib/Baz 2/cmake/BazConfigVersion.cmake

@@ -0,0 +1,7 @@
+set(PACKAGE_VERSION 2.1)
+if("${PACKAGE_FIND_VERSION_MAJOR}" EQUAL 2)
+  set(PACKAGE_VERSION_COMPATIBLE 1)
+  if("${PACKAGE_FIND_VERSION_MINOR}" EQUAL 1)
+    set(PACKAGE_VERSION_EXACT 1)
+  endif()
+endif()

Tests/FindPackageTest/CMakeLists.txt

@@ -102,6 +102,7 @@ endif()
 set(PACKAGES
   foo Foo Bar Blub TFramework Tframework TApp Tapp Special
   VersionedA VersionedB VersionedC VersionedD VersionedE
+  VersionedF VersionedG VersionedH
   WrongA WrongB WrongC WrongD
   wibbleA wibbleB
   RecursiveA RecursiveB RecursiveC
@@ -142,6 +143,10 @@ find_package(VersionedB 3.1 EXACT NAMES zot)
 find_package(VersionedC 4.0 EXACT NAMES zot)
 find_package(VersionedD 1.1 EXACT NAMES Baz)
 find_package(VersionedE 1.2 EXACT NAMES Baz)
+find_package(VersionedF 1.3 EXACT NAMES Baz)
+find_package(VersionedG 2.0 EXACT NAMES Baz)
+find_package(VersionedH 2.1 EXACT NAMES Baz)
+
 
 # Test Config files which set Xyz_FOUND themselves:
 find_package(SetFoundTRUE NO_MODULE)
@@ -158,12 +163,12 @@ find_package(WrongB 1.2 EXACT NAMES Baz)
 
 # Test wrong initial path when result is missing.
 set(WrongC_DIR "${VersionedD_DIR}")
-find_package(WrongC 1.3 EXACT QUIET NAMES Baz)
+find_package(WrongC 1.4 EXACT QUIET NAMES Baz)
 
 # Test wrong initial cache entry of UNINITIALIZED type when result is missing.
 set(WrongD_DIR "${VersionedD_DIR}" CACHE UNINITIALIZED "Wrong Value" FORCE)
 get_property(type CACHE WrongD_DIR PROPERTY TYPE)
-find_package(WrongD 1.3 EXACT QUIET NAMES Baz)
+find_package(WrongD 1.4 EXACT QUIET NAMES Baz)
 
 # HINTS should override the system but PATHS should not
 list(INSERT CMAKE_SYSTEM_PREFIX_PATH 0 "${CMAKE_CURRENT_SOURCE_DIR}/A")
@@ -216,6 +221,9 @@ set(VersionedB_EXPECTED "lib/zot-3.1/zot-config.cmake")
 set(VersionedC_EXPECTED "lib/cmake/zot-4.0/zot-config.cmake")
 set(VersionedD_EXPECTED "Baz 1.1/BazConfig.cmake")
 set(VersionedE_EXPECTED "Baz 1.2/CMake/BazConfig.cmake")
+set(VersionedF_EXPECTED "Baz 1.3/lib/cmake/Baz/BazConfig.cmake")
+set(VersionedG_EXPECTED "Baz 2.0/share/Baz 2/BazConfig.cmake")
+set(VersionedH_EXPECTED "Baz 2.1/lib/Baz 2/cmake/BazConfig.cmake")
 set(WrongA_EXPECTED "${VersionedE_EXPECTED}")
 set(WrongB_EXPECTED "${VersionedE_EXPECTED}")
 set(WrongC_MISSING "WrongC_DIR-NOTFOUND")