[cmake] Recover sibling builds supporting DUNE in build tree

CMakeLists.txt

@@ -916,35 +916,39 @@ if(CONVERT_CUDA_TO_HIP)
   set(USE_GPU_BRIDGE OFF)
 endif()
 
+# These modules are special because they search with the first
+# find_package call in here
+set(initial_depends opm-common dune-common)
+
 if(SIBLING_SEARCH AND NOT opm-common_DIR)
   # guess the sibling dir
   get_filename_component(_leaf_dir_name ${PROJECT_BINARY_DIR} NAME)
   get_filename_component(_parent_full_dir ${PROJECT_BINARY_DIR} DIRECTORY)
   get_filename_component(_parent_dir_name ${_parent_full_dir} NAME)
   #Try if <module-name>/<build-dir> is used
   get_filename_component(_modules_dir ${_parent_full_dir} DIRECTORY)
-  if(IS_DIRECTORY ${_modules_dir}/opm-common/${_leaf_dir_name})
-    set(opm-common_DIR ${_modules_dir}/opm-common/${_leaf_dir_name})
-    set(opm-grid_DIR ${_modules_dir}/opm-grid/${_leaf_dir_name})
-  else()
-    string(REPLACE ${PROJECT_NAME} opm-common _opm_common_leaf ${_leaf_dir_name})
-    if(NOT _leaf_dir_name STREQUAL _opm_common_leaf
-        AND IS_DIRECTORY ${_parent_full_dir}/${_opm_common_leaf})
-      # We are using build directories named <prefix><module-name><postfix>
-      set(opm-common_DIR ${_parent_full_dir}/${_opm_common_leaf})
-      string(REPLACE ${PROJECT_NAME} opm-grid _opm_grid_leaf ${_leaf_dir_name})
-      set(opm-grid_DIR ${_parent_full_dir}/${_opm_grid_leaf})
-    elseif(IS_DIRECTORY ${_parent_full_dir}/opm-common)
-      # All modules are in a common build dir
-      set(opm-common_DIR "${_parent_full_dir}/opm-common")
-      set(opm-grid_DIR "${_parent_full_dir}/opm-grid")
+  foreach(module ${initial_depends})
+    if(IS_DIRECTORY ${_modules_dir}/${module}/${_leaf_dir_name})
+      set(${module}_DIR ${_modules_dir}/${module}/${_leaf_dir_name})
+    else()
+      string(REPLACE ${PROJECT_NAME} ${module} _module_leaf ${_leaf_dir_name})
+      if(NOT _leaf_dir_name STREQUAL _module_leaf
+          AND IS_DIRECTORY ${_parent_full_dir}/${_module_leaf})
+        # We are using build directories named <prefix><module-name><postfix>
+        set(${module}_DIR ${_parent_full_dir}/${_module_leaf})
+      elseif(IS_DIRECTORY ${_parent_full_dir}/${module})
+        # All modules are in a common build dir
+        set(${module}_DIR "${_parent_full_dir}/${module}")
+      endif()
     endif()
-  endif()
-endif()
-if(opm-common_DIR AND NOT IS_DIRECTORY ${opm-common_DIR})
-  message(WARNING "Value ${opm-common_DIR} passed to variable"
-    " opm-common_DIR is not a directory")
+  endforeach()
 endif()
+foreach(module ${initial_depends})
+  if(${module}_DIR AND NOT IS_DIRECTORY ${${module}_DIR})
+    message(WARNING "Value ${${module}_DIR} passed to variable"
+      " ${module}_DIR is not a directory")
+  endif()
+endforeach()
 
 find_package(opm-common REQUIRED)
 

dune.module

@@ -10,4 +10,8 @@ Label: 2026.10-pre
 Maintainer: atgeirr@sintef.no
 MaintainerName: Atgeirr F. Rasmussen
 Url: http://opm-project.org
-Depends: dune-istl (>= 2.9) opm-common opm-grid
+# We need the full list of dependencies below, because we need to set
+# *_DIR for each of them when doing a sibling build (done using
+# CMakeLists.txt and cmake/Module/OpmSiblingSearch.cmake).
+Depends: dune-istl (>= 2.9) opm-common dune-grid (>= 2.9) dune-geometry (>= 2.9) opm-grid
+Suggests: dune-uggrid (>= 2.9) dune-fem (>= 2.9) dune-alugrid (>= 2.9) dune-localfunctions (>= 2.9)