Silence CMake warnings ECFLOW-1936

Silence CMake warnings regarding the policies: CMP0046, CMP0144 and CMP0148

CMakeLists.txt

@@ -63,6 +63,7 @@ option( ENABLE_HTTP                "Enable HTTP server (experimental)" ON  )
 option( ENABLE_UDP                 "Enable UDP server (experimental)" ON )
 option( ENABLE_DOCS                "Enable Documentation" OFF )
 
+include(Policies NO_POLICY_SCOPE)
 
 # =========================================================================================
 # Dependency: Qt

Pyext/CMakeLists.txt

@@ -196,6 +196,7 @@ else()
         find_package( Boost ${ECFLOW_BOOST_VERSION} COMPONENTS ${ECFLOW_BOOST_PYTHON_COMPONENT} )
 
         if (Boost_PYTHON_FOUND OR Boost_PYTHON${Python2_VERSION_MAJOR}${Python2_VERSION_MINOR}_FOUND)
+          # Indicate that both Python and Boost.Python have been found
           set(ECF_PYTHON_FOUND "ECF_PYTHON_FOUND")
           add_subdirectory( python2 )
         else()
@@ -226,6 +227,11 @@ else()
     message( STATUS "  Python3_VERSION_MINOR             : ${Python3_VERSION_MINOR}" )
     message( STATUS "  Python3_VERSION_PATCH             : ${Python3_VERSION_PATCH}" )
 
+    # Set (deprecated) FindPython variables
+    # These need to be available, as they are used by `ecbuild_add_test(... TYPE PYTHON ...)`
+    set(PYTHONINTERP_FOUND "${Python3_Interpreter_FOUND}")
+    set(PYTHON_EXECUTABLE "${Python3_EXECUTABLE}")
+
     if ( Boost_MINOR_VERSION GREATER 66 )
       # cmake 3.15
       # see: https://gitlab.kitware.com/cmake/cmake/issues/19656
@@ -235,15 +241,11 @@ else()
       set(ECFLOW_BOOST_PYTHON_COMPONENT python3)
     endif()
     find_package( Boost ${ECFLOW_BOOST_VERSION} COMPONENTS ${ECFLOW_BOOST_PYTHON_COMPONENT} )
-    
+
     if (Boost_PYTHON3_FOUND OR Boost_PYTHON${Python3_VERSION_MAJOR}${Python3_VERSION_MINOR}_FOUND)
-      if ( Python3_LIBRARIES )
-        ecbuild_find_python( VERSION ${Python3_VERSION} REQUIRED )
-        set(ECF_PYTHON_FOUND "ECF_PYTHON_FOUND")
-        add_subdirectory( python3 )
-      else()
-        message( STATUS "  python3 libraries *NOT* found" )
-      endif()
+      # Indicate that both Python and Boost.Python have been found
+      set(ECF_PYTHON_FOUND "ECF_PYTHON_FOUND")
+      add_subdirectory( python3 )
     else()
       message( STATUS "  Boost python3 libraries *NOT* found" )
     endif()

Viewer/CMakeLists.txt

@@ -8,20 +8,5 @@
 # nor does it submit to any jurisdiction.
 #
 
-# avoid warning about dependency targets that don't exist
-#
-# CMake Warning (dev) at Viewer/src/CMakeLists.txt:261 (ADD_DEPENDENCIES):
-#  Policy CMP0046 is not set: Error on non-existent dependency in
-#  add_dependencies.  Run "cmake --help-policy CMP0046" for policy details.
-#  Use the cmake_policy command to set the policy and suppress this warning.
-#
-#  The dependency target
-#  "/tmp/ma0/workspace/ecflow/Viewer/src/../images/zombie_dock.svg" of target
-#  "Qt_resource_cpp" does not exist.
-
-if (POLICY CMP0046)
-  cmake_policy(SET CMP0046 OLD)
-endif()
-
 add_subdirectory( libViewer)
 add_subdirectory( ecflowUI)

Viewer/ecflowUI/src/CMakeLists.txt

@@ -795,8 +795,7 @@ endif()
 # add all the images as dependencies of the resource file so that it is
 # automatically recompiled when an image changes
 file(GLOB image_files "${CMAKE_CURRENT_SOURCE_DIR}/../images/*.*")
-add_custom_target(Qt_resource_cpp DEPENDS ${VIEWER_RES})
-add_dependencies(Qt_resource_cpp ${image_files})
+add_custom_target(Qt_resource_cpp DEPENDS ${VIEWER_RES} ${image_files})
 
 ecbuild_add_executable(
   TARGET

cmake/Policies.cmake

@@ -0,0 +1,27 @@
+#
+# Copyright 2009- ECMWF.
+#
+# This software is licensed under the terms of the Apache Licence version 2.0
+# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+# In applying this licence, ECMWF does not waive the privileges and immunities
+# granted to it by virtue of its status as an intergovernmental organisation
+# nor does it submit to any jurisdiction.
+#
+
+# =========================================================================================
+# Setup project-wide CMake Policies
+# =========================================================================================
+
+#
+# CMake Policy CMP0144 (CMake >=3.27)
+#
+# OLD behaviour:
+#   find_package(PackageName) used only case-preserved <PackageName>_ROOT variables
+#
+# NEW behaviour:
+#   find_package(PackageName) uses upper-case <PACKAGENAME>_ROOT variables,
+#     in addition to <PackageName>_ROOT variables.
+#
+if(POLICY CMP0144)
+  cmake_policy(SET CMP0144 NEW)
+endif()