.testing: Use Fortran to generate tc inputs

This patch removes the `build_{grid,data}.py` scripts from .testing's
tc4, along with the setup of the Python infrastructure used in the
.testing Makefile and GitHub Actions CI.

The Python scripts have been replaced with equivalent Fortran programs
which generate identical netCDF output.

A new rule (`preproc`) has been added to the .testing top Makefile for
generating the model input files.

The netCDF compiler dependenices are configured with autoconf, currently
duplicating the macros in `ac/configure.ac`. (NOTE: It may be possible
to share these with a common macro in ac/m4.

The configure script and Makefile are currently generated from
`configure.ac` and `autoreconf`.  In the future, we could simply
pre-generate `configure` and add it to the repository.

This patch was motivated by the inability to install recent
netCDF-Python packages on systems with older gcc compilers, including
our main production machine.  We could have possibly resolved this by
adding compiler configuration to pip, or perhaps reported the issue to
the netCDF-python project for them to resolve.  But the costs of relying
on all this Python infrastructure is starting to exceed the benefits,
and I would recommend we excise it from our test suite.

.github/actions/testing-setup/action.yml

@@ -5,10 +5,6 @@ inputs:
     description: 'If true, will build the symmetric MOM6 executable'
     required: false
     default: 'true'
-  install_python:
-    description: 'If true, will install the local python env needed for .testing'
-    required: false
-    default: 'true'
 runs:
   using: 'composite'
   steps:
@@ -54,14 +50,6 @@ runs:
         test ${{ inputs.build_symmetric }} == true && make build/symmetric/MOM6 -j
         echo "::endgroup::"
 
-    - name: Install local python venv for generating input data
-      shell: bash
-      run: |
-        echo "::group::Create local python env for input data generation"
-        cd .testing
-        test ${{ inputs.install_python }} == true && make work/local-env
-        echo "::endgroup::"
-
     - name: Set flags
       shell: bash
       run: |

.github/workflows/coupled-api.yml

@@ -20,7 +20,6 @@ jobs:
     - uses: ./.github/actions/testing-setup
       with:
         build_symmetric: 'false'
-        install_python: 'false'
 
     - name: Compile MOM6 for the GFDL coupled driver
       shell: bash

.testing/Makefile

@@ -11,7 +11,7 @@
 #       Delete the MOM6 test executables and dependency builds (FMS)
 #
 #   make clean.build
-#   	Delete only the MOM6 test executables
+#       Delete only the MOM6 test executables
 #
 #
 # Configuration:
@@ -204,34 +204,11 @@ endif
 FMS_SOURCE = $(call SOURCE,deps/fms/src)
 
 
-#---
-# Python preprocessing environment configuration
-
-HAS_NUMPY = $(shell python -c "import numpy" 2> /dev/null && echo "yes")
-HAS_NETCDF4 = $(shell python -c "import netCDF4" 2> /dev/null && echo "yes")
-
-USE_VENV =
-ifneq ($(HAS_NUMPY), yes)
-  USE_VENV = yes
-endif
-ifneq ($(HAS_NETCDF4), yes)
-  USE_VENV = yes
-endif
-
-# When disabled, activation is a null operation (`true`)
-VENV_PATH =
-VENV_ACTIVATE = true
-ifeq ($(USE_VENV), yes)
-  VENV_PATH = work/local-env
-  VENV_ACTIVATE = . $(VENV_PATH)/bin/activate
-endif
-
-
 #---
 # Rules
 
 .PHONY: all build.regressions build.prof
-all: $(foreach b,$(BUILDS),build/$(b)) $(VENV_PATH)
+all: $(foreach b,$(BUILDS),build/$(b))
 build.regressions: $(foreach b,symmetric target,build/$(b)/MOM6)
 build.prof: $(foreach b,opt opt_target,build/$(b)/MOM6)
 
@@ -382,8 +359,8 @@ deps/Makefile: ../ac/deps/Makefile
 # broken the ability to compile.  This is not a means to build a complete
 # coupled executable.
 # TODO:
-# 	- Avoid re-building FMS and MOM6 src by re-using existing object/mod files
-# 	- Use autoconf rather than mkmf templates
+#   - Avoid re-building FMS and MOM6 src by re-using existing object/mod files
+#   - Use autoconf rather than mkmf templates
 MK_TEMPLATE ?= ../../deps/mkmf/templates/ncrc-gnu.mk
 
 # NUOPC driver
@@ -402,21 +379,6 @@ build/mct/mom_ocean_model_mct.o: build/mct/Makefile
 check_mom6_api_mct: build/mct/mom_ocean_model_mct.o
 
 
-#---
-# Python preprocessing
-
-# NOTE: Some less mature environments (e.g. Arm64 Ubuntu) require explicit
-#   installation of numpy before netCDF4, as well as wheel and cython support.
-work/local-env:
-	python3 -m venv $@
-	. $@/bin/activate \
-	  && python3 -m pip install --upgrade pip \
-	  && pip3 install wheel \
-	  && pip3 install cython \
-	  && pip3 install numpy \
-	  && pip3 install netCDF4
-
-
 #---
 # Testing
 
@@ -555,6 +517,20 @@ $(foreach c,$(CONFIGS),$(eval $(call CONFIG_DIM_RULE,$(c))))
 	@echo -e "$(PASS): Diagnostics $*.regression.diag agree."
 
 
+#---
+# Preprocessing
+# NOTE: This only support tc4, but can be generalized over all tests.
+.PHONY: preproc
+preproc: tc4/Makefile
+	cd tc4 && make
+
+tc4/Makefile: tc4/configure tc4/Makefile.in
+	cd $(@D) && ./configure || (cat config.log && false)
+
+tc4/configure: tc4/configure.ac
+	cd $(@D) && autoreconf -if
+
+
 #---
 # Test run output files
 
@@ -567,17 +543,10 @@ $(foreach c,$(CONFIGS),$(eval $(call CONFIG_DIM_RULE,$(c))))
 # $(6): Number of MPI ranks
 
 define STAT_RULE
-work/%/$(1)/ocean.stats work/%/$(1)/chksum_diag: build/$(2)/MOM6 $(VENV_PATH)
+work/%/$(1)/ocean.stats work/%/$(1)/chksum_diag: build/$(2)/MOM6 | preproc
 	@echo "Running test $$*.$(1)..."
 	mkdir -p $$(@D)
 	cp -RL $$*/* $$(@D)
-	if [ -f $$(@D)/Makefile ]; then \
-	  $$(VENV_ACTIVATE) \
-	    && cd $$(@D) \
-	    && $(MAKE); \
-	else \
-	  cd $$(@D); \
-	fi
 	mkdir -p $$(@D)/RESTART
 	echo -e "$(4)" > $$(@D)/MOM_override
 	rm -f results/$$*/std.$(1).{out,err}
@@ -615,7 +584,7 @@ report.cov: run.cov codecov
 	  || { \
 	    cat build/cov/codecov.err ; \
 	    echo -e "${RED}Failed to upload report.${RESET}" ; \
-		if [ "$(REQUIRE_COVERAGE_UPLOAD)" = true ] ; then false ; fi ; \
+	    if [ "$(REQUIRE_COVERAGE_UPLOAD)" = true ] ; then false ; fi ; \
 	  }
 
 # Define $(,) as comma escape character
@@ -643,17 +612,10 @@ $(eval $(call STAT_RULE,cov,cov,true,,,1))
 #  2. Convert DAYMAX from TIMEUNIT to seconds
 #  3. Apply seconds to `ocean_solo_nml` inside input.nml.
 # NOTE: Assumes that runtime set by DAYMAX, will fail if set by input.nml
-work/%/restart/ocean.stats: build/symmetric/MOM6 $(VENV_PATH)
+work/%/restart/ocean.stats: build/symmetric/MOM6 | preproc
 	rm -rf $(@D)
 	mkdir -p $(@D)
 	cp -RL $*/* $(@D)
-	if [ -f $(@D)/Makefile ]; then \
-	  $(VENV_ACTIVATE) \
-	    && cd work/$*/restart \
-	    && $(MAKE); \
-	else \
-	  cd work/$*/restart; \
-	fi
 	mkdir -p $(@D)/RESTART
 	# Set the half-period
 	cd $(@D) \
@@ -754,7 +716,7 @@ report.cov.unit: build/unit/MOM_file_parser_tests.F90.gcov codecov
 	  || { \
 	    cat build/unit/codecov.err ; \
 	    echo -e "${RED}Failed to upload report.${RESET}" ; \
-		if [ "$(REQUIRE_COVERAGE_UPLOAD)" = true ] ; then false ; fi ; \
+	    if [ "$(REQUIRE_COVERAGE_UPLOAD)" = true ] ; then false ; fi ; \
 	  }
 
 
@@ -833,6 +795,13 @@ clean.build:
 
 
 .PHONY: clean.stats
-clean.stats:
+clean.stats: clean.preproc
 	@[ $$(basename $$(pwd)) = .testing ]
 	rm -rf work results
+
+
+.PHONY: clean.preproc
+clean.preproc:
+	@if [ -f tc4/Makefile ] ; then \
+	  cd tc4 && make clean ; \
+	fi

.testing/tc4/.gitignore

@@ -1,4 +1,15 @@
+# Autoconf
+aclocal.m4
+autom4te.cache/
+config.log
+config.status
+configure~
+
+# Output
+gen_grid
 ocean_hgrid.nc
+topog.nc
+
+gen_data
 sponge.nc
 temp_salt_ic.nc
-topog.nc

.testing/tc4/Makefile.in

@@ -0,0 +1,38 @@
+FC = @FC@
+LD = @LD@
+FCFLAGS = @FCFLAGS@
+LDFLAGS = @LDFLAGS@
+LIBS = @LIBS@
+
+OUT = topog.nc ocean_hgrid.nc temp_salt_ic.nc sponge.nc
+
+all: $(OUT)
+
+ocean_hgrid.nc topog.nc: gen_grid
+	./gen_grid
+
+temp_salt_ic.nc sponge.nc: gen_data
+	./gen_data
+
+gen_grid: gen_grid.F90
+	$(FC) $(FCFLAGS) $(LDFLAGS) -o $@ $^ $(LIBS)
+
+gen_data: gen_data.F90
+	$(FC) $(FCFLAGS) $(LDFLAGS) -o $@ $^ $(LIBS)
+
+.PHONY: clean
+clean:
+	rm -rf $(OUT) gen_grid gen_data
+
+.PHONY: distclean
+distclean: clean
+	rm -f config.log
+	rm -f config.status
+	rm -f Makefile
+
+.PHONY: ac-clean
+ac-clean: distclean
+	rm -f aclocal.m4
+	rm -rf autom4te.cache
+	rm -f configure
+	rm -f configure~