fix(test_rhog_io): keep __MPI per-target so the MPI test initializes MPI

The test aborted with "MPI_Comm_rank() called before MPI_INIT" because the
directory-level abacus_disable_feature_definitions(__MPI) in
source_estate/test stripped __MPI from every target there. With __MPI gone,
the test's main() never called MPI_Init, while the linked base/planewave
libraries still issue real MPI calls.

Add a target-level escape hatch: a new ABACUS_KEPT_FEATURE_DEFINITIONS
target property (exposed as AddTest's KEEP_FEATURE_DEFINITIONS) lets a
single target keep definitions its directory disables. Use it for this
test, link planewave instead of planewave_serial, and copy the support/
data at configure time (install() is skipped by plain make+ctest).

Also fix test bugs hidden while __MPI was stripped: drop const from kpar
(passed by reference to divide_pools), call setup_pw_basis() in the three
tests that need a valid grid, and set npwtot=1000 in InconsistentGammaOnly
to trigger the expected "planewaves not used" warning.

Verified: make MODULE_ESTATE_test_rhog_io && ctest -R
MODULE_ESTATE_test_rhog_io -> 10/10 passed.

Author: abacus_fixer

cmake/Testing.cmake

@@ -32,9 +32,17 @@ endif()
 
  function(AddTest) # function for UT
     cmake_parse_arguments(UT "DYN" "TARGET"
-                          "LIBS;DYN_LIBS;STATIC_LIBS;SOURCES;DEPENDS" ${ARGN})
+                          "LIBS;DYN_LIBS;STATIC_LIBS;SOURCES;DEPENDS;KEEP_FEATURE_DEFINITIONS" ${ARGN})
     add_executable(${UT_TARGET} ${UT_SOURCES})
 
+    # Let this target keep feature definitions (e.g. __MPI) that its source
+    # directory disables via abacus_disable_feature_definitions(). Needed by
+    # tests that genuinely exercise the feature.
+    if(UT_KEEP_FEATURE_DEFINITIONS)
+      set_property(TARGET ${UT_TARGET} PROPERTY
+        ABACUS_KEPT_FEATURE_DEFINITIONS ${UT_KEEP_FEATURE_DEFINITIONS})
+    endif()
+
     if(ENABLE_COVERAGE)
       add_coverage(${UT_TARGET})
     endif()

source/CMakeLists.txt

@@ -417,6 +417,15 @@ define_property(
   BRIEF_DOCS "Additional ABACUS feature definitions for targets in this directory"
   FULL_DOCS "Additional feature definitions for targets created in this directory.")
 
+define_property(
+  TARGET
+  PROPERTY ABACUS_KEPT_FEATURE_DEFINITIONS
+  BRIEF_DOCS "Feature definitions this target keeps despite a directory-level disable"
+  FULL_DOCS "Feature definitions that must not be stripped from this target even "
+    "when its source directory disables them via "
+    "abacus_disable_feature_definitions(). Used by tests that genuinely need a "
+    "feature (e.g. __MPI) inside a directory that otherwise disables it.")
+
 function(abacus_disable_feature_definitions)
   abacus_normalize_definitions(_defs ${ARGN})
   set_property(DIRECTORY APPEND PROPERTY
@@ -448,7 +457,12 @@ function(abacus_apply_build_options target)
   set(_defs "${_abacus_feature_definitions}")
   get_property(_disabled DIRECTORY "${_source_dir}" PROPERTY ABACUS_DISABLED_FEATURE_DEFINITIONS)
   get_property(_local DIRECTORY "${_source_dir}" PROPERTY ABACUS_LOCAL_FEATURE_DEFINITIONS)
+  get_target_property(_kept "${target}" ABACUS_KEPT_FEATURE_DEFINITIONS)
 
+  if(_kept)
+    # A target may opt back into definitions its directory disables.
+    list(REMOVE_ITEM _disabled ${_kept})
+  endif()
   if(_disabled)
     # Filter after conditional definitions have been evaluated.
     string(JOIN "|" _disabled_regex ${_disabled})

source/source_estate/test/CMakeLists.txt

@@ -9,6 +9,9 @@ abacus_disable_feature_definitions(_OPENMP)
 
 if (ENABLE_MPI)
 
+# Copy at configure time so a plain `make` + `ctest` run finds the data.
+# install() only runs during `cmake --install`, which local test runs skip.
+file(COPY support DESTINATION ${CMAKE_CURRENT_BINARY_DIR})
 install(DIRECTORY support DESTINATION ${CMAKE_CURRENT_BINARY_DIR})
 
 AddTest(
@@ -115,8 +118,12 @@ AddTest(
 
 AddTest(
   TARGET MODULE_ESTATE_test_rhog_io
-  LIBS parameter base device planewave_serial
+  LIBS parameter base device planewave
   SOURCES test_rhog_io.cpp ../rhog_io.cpp ../../source_basis/module_pw/test/test_tool.cpp
+  # This test drives PW_Basis::initmpi and read/write_rhog's MPI collectives,
+  # so it must keep __MPI even though this directory disables it. Its main()
+  # calls MPI_Init via test_tool.cpp's setupmpi().
+  KEEP_FEATURE_DEFINITIONS __MPI
 )
 
 endif()

source/source_estate/test/test_rhog_io.cpp

@@ -91,6 +91,7 @@ TEST_F(ReadRhogTest, ReadRhog)
 // Test the read_rhog function when the file is not found
 TEST_F(ReadRhogTest, NotFoundFile)
 {
+    setup_pw_basis();
     std::string filename = "notfound.txt";
 
     open_warning("test_read_rhog.txt");
@@ -106,8 +107,12 @@ TEST_F(ReadRhogTest, NotFoundFile)
 // Test the read_rhog function when gamma_only is inconsistent
 TEST_F(ReadRhogTest, InconsistentGammaOnly)
 {
+    setup_pw_basis();
     std::string filename = "./support/charge-density.dat";
     rhopw.gamma_only = true;
+    // Fewer planewaves than the file holds (1471) triggers the
+    // "some planewaves in file are not used" warning.
+    rhopw.npwtot = 1000;
 
     open_warning("test_read_rhog.txt");
     bool result = elecstate::read_rhog(filename, &rhopw, 2, rhog.data(), pw_world, &warning_stream);
@@ -126,6 +131,7 @@ TEST_F(ReadRhogTest, InconsistentGammaOnly)
 // Test the read_rhog function when some planewaves in file are missing
 TEST_F(ReadRhogTest, SomePWMissing)
 {
+    setup_pw_basis();
     std::string filename = "./support/charge-density.dat";
     rhopw.npwtot = 2000;
 
@@ -383,7 +389,7 @@ int main(int argc, char** argv)
     int nproc = 1;
     int myrank = 0;
     int nproc_in_pool = 1;
-    const int kpar = 1;
+    int kpar = 1;
     int mypool = 0;
     int rank_in_pool = 0;
     setupmpi(argc, argv, nproc, myrank);