refactor(params): consolidate codegen, eliminate duplicate description/namelist systems

- Delete namelist_targets.py: NAMELIST_VARS moved to definitions.py (one file to
  edit when adding a param); CASE_OPT_EXCLUDE was a duplicate of CASE_OPT_PARAMS

- Delete _FALLBACK_PARAMS (380 hardcoded lines) in namelist_parser.py: replaced
  by _fallback_params() that derives the same data from NAMELIST_VARS at runtime

- Delete _SIMPLE_DESCS (145 lines) and _auto_describe in definitions.py: _r() now
  populates ParamDef.description from descriptions.get_description() so callers
  can read param.description directly; three callers (docs_gen, json_schema_gen,
  params_cmd) migrated off the external get_description() import

- Delete _PREFIX_DESCS and _ATTR_DESCS (113 lines) in definitions.py: dead code
  after _auto_describe was removed

- Add resolve_namelist_content() and TARGET_FROM_DIR to fortran_gen.py: single
  canonical helper for the detect-generated-include pattern duplicated across
  namelist_parser.py and lint_param_docs.py

- Consolidate NAMELIST_VARS to use _nv() helper: 200-line explicit dict replaced
  by grouped calls (~75 lines); cmake_gen.py refactored to use get_generated_files()

- Switch test runner from hardcoded unittest module list to pytest discover; add
  pytest to pyproject.toml; move three orphaned test files into params_tests/

- CMake: stamp-based caching so Fortran codegen only reruns when inputs change

- Extract _format_constraints_cell() in docs_gen.py: 5-line pattern duplicated
  across pattern-view and full-table rendering paths

- Inline 4 single-use wrapper functions in case_dicts.py

Net vs master: -564 lines

Author: sbryngelson

CMakeLists.txt

@@ -464,16 +464,37 @@ endmacro()
 # Generate Fortran parameter namelist/decl includes into the per-target build
 # include directories before HANDLE_SOURCES globs them for Fypp.
 find_package(Python3 REQUIRED COMPONENTS Interpreter)
-execute_process(
-    COMMAND "${Python3_EXECUTABLE}"
-            "${CMAKE_CURRENT_SOURCE_DIR}/toolchain/mfc/params/generators/cmake_gen.py"
-            "${CMAKE_BINARY_DIR}"
-    WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
-    RESULT_VARIABLE _mfc_gen_result
-    ERROR_VARIABLE  _mfc_gen_error
+set(_mfc_gen_stamp "${CMAKE_BINARY_DIR}/mfc_params_gen.stamp")
+set(_mfc_gen_inputs
+    "${CMAKE_CURRENT_SOURCE_DIR}/toolchain/mfc/params/generators/cmake_gen.py"
+    "${CMAKE_CURRENT_SOURCE_DIR}/toolchain/mfc/params/generators/fortran_gen.py"
+    "${CMAKE_CURRENT_SOURCE_DIR}/toolchain/mfc/params/namelist_targets.py"
+    "${CMAKE_CURRENT_SOURCE_DIR}/toolchain/mfc/params/definitions.py"
 )
-if(NOT _mfc_gen_result EQUAL 0)
-    message(FATAL_ERROR "Fortran param generation failed:\n${_mfc_gen_error}")
+set(_mfc_needs_regen FALSE)
+if(NOT EXISTS "${_mfc_gen_stamp}")
+    set(_mfc_needs_regen TRUE)
+else()
+    foreach(_input IN LISTS _mfc_gen_inputs)
+        if("${_input}" IS_NEWER_THAN "${_mfc_gen_stamp}")
+            set(_mfc_needs_regen TRUE)
+            break()
+        endif()
+    endforeach()
+endif()
+if(_mfc_needs_regen)
+    execute_process(
+        COMMAND "${Python3_EXECUTABLE}"
+                "${CMAKE_CURRENT_SOURCE_DIR}/toolchain/mfc/params/generators/cmake_gen.py"
+                "${CMAKE_BINARY_DIR}"
+        WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+        RESULT_VARIABLE _mfc_gen_result
+        ERROR_VARIABLE  _mfc_gen_error
+    )
+    if(NOT _mfc_gen_result EQUAL 0)
+        message(FATAL_ERROR "Fortran param generation failed:\n${_mfc_gen_error}")
+    endif()
+    file(TOUCH "${_mfc_gen_stamp}")
 endif()
 
 HANDLE_SOURCES(pre_process ON)

src/simulation/m_global_parameters.fpp

@@ -70,8 +70,6 @@ module m_global_parameters
         integer :: num_dims  !< Number of spatial dimensions
         integer :: num_vels  !< Number of velocity components (different from num_dims for mhd)
     #:endif
-    ! mpp_lim, time_stepper, prim_vars_wrt now in generated_decls.fpp
-
     #:if MFC_CASE_OPTIMIZATION
         integer, parameter :: recon_type = ${recon_type}$    !< Reconstruction type
         integer, parameter :: weno_polyn = ${weno_polyn}$    !< Degree of the WENO polynomials (polyn)

toolchain/bootstrap/lint.sh

@@ -32,12 +32,8 @@ ruff check benchmarks/*/case.py
 if [ "$RUN_TESTS" = true ]; then
     log "(venv) Running$MAGENTA unit tests$COLOR_RESET on$MAGENTA MFC$COLOR_RESET's $MAGENTA""toolchain$COLOR_RESET."
 
-    # Run tests as modules from the toolchain directory to resolve relative imports
     cd toolchain
-    python3 -m unittest mfc.params_tests.test_registry mfc.params_tests.test_definitions mfc.params_tests.test_validate mfc.params_tests.test_integration -v
-    python3 -m unittest mfc.cli.test_cli -v
-    python3 -m unittest mfc.viz.test_viz -v
-    python3 -m unittest mfc.run.test_archive -v
+    python3 -m pytest . -v
     cd - > /dev/null
 fi
 

toolchain/mfc/lint_param_docs.py

@@ -80,49 +80,6 @@ def _param_appears_in_case_md(param_base: str, tokens: set[str], text: str) -> b
     return False
 
 
-def _parse_namelist_params(fpp_path: Path) -> set[str]:
-    """Parse parameter names from a namelist /user_inputs/ block in an fpp file."""
-    text = fpp_path.read_text(encoding="utf-8")
-
-    # If the namelist is in a #:include'd generated file, generate in-memory.
-    if re.search(r"#:include\s+'generated_namelist\.fpp'", text):
-        _target_map = {"pre_process": "pre", "simulation": "sim", "post_process": "post"}
-        short = _target_map.get(fpp_path.parent.name)
-        if short:
-            from mfc.params.generators.fortran_gen import generate_namelist_fpp
-
-            text = generate_namelist_fpp(short)
-
-    params = set()
-
-    in_namelist = False
-    accum = ""
-    for line in text.splitlines():
-        stripped = line.strip()
-        if stripped.startswith("!") or stripped.startswith("#:") or stripped.startswith("#"):
-            continue
-        lower = stripped.lower()
-        if "namelist /user_inputs/" in lower:
-            idx = lower.index("/user_inputs/") + len("/user_inputs/")
-            accum += " " + stripped[idx:]
-            in_namelist = accum.rstrip().endswith("&")
-            continue
-        if in_namelist:
-            if stripped.startswith("&"):
-                stripped = stripped[1:]
-            accum += " " + stripped
-            if not accum.rstrip().endswith("&"):
-                in_namelist = False
-
-    accum = accum.replace("&", " ")
-    for raw_token in accum.split(","):
-        name = raw_token.strip()
-        if name and re.match(r"^[a-zA-Z_]\w*$", name):
-            params.add(name)
-
-    return params
-
-
 def check_descriptions_in_case_md(repo_root: Path) -> list[str]:
     """Tier 1, Check 1+2: Params with DESCRIPTIONS entries should appear in case.md."""
     REGISTRY, DESCRIPTIONS = _import_registry(repo_root)
@@ -185,13 +142,14 @@ def _is_derived_type_parent_or_field(name: str, all_params: dict) -> bool:
 def check_namelist_registry_sync(repo_root: Path) -> list[str]:
     """Tier 2: Unknown Fortran namelist params must be in REGISTRY (blocking)."""
     REGISTRY, _ = _import_registry(repo_root)
+    from mfc.params.namelist_parser import parse_namelist_from_file
 
     errors = []
     startup_files = sorted((repo_root / "src").rglob("m_start_up.fpp"))
     all_params = REGISTRY.all_params
 
     for fpp in startup_files:
-        nl_params = _parse_namelist_params(fpp)
+        nl_params = parse_namelist_from_file(fpp)
         rel = fpp.relative_to(repo_root)
 
         for p in sorted(nl_params):