Make ResdataKW.read_grdecl use pybind

[eivindjahren]

Also fixes a segfault for zero-length min_max.

With regards to returning None or not, I changed the documentation of "If the keyword can not be found the method will return None." This is because we consider this legacy code so its more likely that someone depends on behavior rather than documentation.

[Copilot]

Pull request overview

This PR migrates GRDECL keyword I/O for ResdataKW from the old cwrap/ctypes prototype layer to a new pybind11 extension (resdata.resfile._kw), while refactoring the underlying C++ GRDECL reader/writer APIs and updating C++/Python tests accordingly.

Changes:

• Added a new pybind11 module (_kw) and switched ResdataKW.read_grdecl, fseek_grdecl, and write_grdecl to use it.
• Refactored GRDECL parsing/writing in C++ (rd_kw_grdecl.*) to use exceptions/RAII and updated call sites to the new function signatures.
• Added Python tests for empty GRDECL bodies and strict-mode malformed token errors.

Reviewed changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
tests/rd_tests/test_rd_kw.py	Adds new Python regression tests for GRDECL reading (empty + malformed strict parsing).
python/resdata/resfile/rd_kw.py	Switches GRDECL read/seek/write paths to the new pybind module and adjusts get_min_max for empty keywords.
lib/tests/test_rd_grid_misc.cpp	Updates GRDECL read helper to new rd_kw_fscanf_alloc_grdecl argument order.
lib/resdata/tests/rd_layer_equinor.cpp	Updates GRDECL keyword read call + includes new GRDECL header.
lib/resdata/tests/rd_kw_grdecl.cpp	Updates GRDECL read/write tests to new APIs (including “special header” printing).
lib/resdata/tests/rd_kw_fread.cpp	Updates GRDECL read call ordering + includes GRDECL header.
lib/resdata/tests/rd_fault_block_layer_equinor.cpp	Updates GRDECL keyword read call ordering + includes GRDECL header.
lib/resdata/rd_type.cpp	Introduces rd_type_name() returning std::string for improved error formatting.
lib/resdata/rd_type_python.cpp	Removes the old GRDECL dynamic python shim function (no longer needed with pybind).
lib/resdata/rd_kw.cpp	Makes max/min on zero-length keywords abort (paired with Python-side guard).
lib/resdata/rd_kw_pybind.cpp	New pybind11 module providing GRDECL load/seek/print entry points for Python.
lib/resdata/rd_kw_grdecl.cpp	Refactors GRDECL parsing/writing; changes APIs and error handling to exceptions.
lib/resdata/rd_grid.cpp	Updates GRDECL printing to use new rd_kw_fprintf_grdecl API.
lib/include/resdata/rd_type.hpp	Declares new rd_type_name() C++ API.
lib/include/resdata/rd_kw.hpp	Removes implicit inclusion of rd_kw_grdecl.hpp (callers now include explicitly).
lib/include/resdata/rd_kw_grdecl.hpp	Reworks GRDECL header declarations (now C++-style with optional “special header”).
lib/CMakeLists.txt	Adds build/install rules for the new _kw pybind module.
applications/resdata/grdecl_test.cpp	Updates deprecated app to new GRDECL read API.

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[Copilot]

Pull request overview

Copilot reviewed 18 out of 18 changed files in this pull request and generated 3 comments.

Comments suppressed due to low confidence (1)

lib/resdata/rd_kw_grdecl.cpp:12

• rd_kw_grdecl.cpp implements public functions (rd_kw_fscanf_alloc_grdecl, rd_kw_fprintf_grdecl) but does not include its corresponding public header rd_kw_grdecl.hpp. This makes it easy for the implementation signature to drift from the installed API without the compiler noticing. Consider including resdata/rd_kw_grdecl.hpp here and moving default arguments to the header only (omit them from the definition) to ensure consistency.

#include <cstring>
#include <cctype>
#include <optional>
#include <memory>

#include <ert/util/util.hpp>
#include <fmt/format.h>

#include <resdata/rd_kw.hpp>
#include <resdata/rd_type.hpp>
#include <resdata/rd_util.hpp>

[ajaust]

I have mostly minor points. I have some concerns how checked_realloc is defined vs. how it is used (using element count vs byte size for allocation).

I don't know if all my comments appear at the correct location nor whether they are still all relevent. Some commits changed while I was preparing the review. Therefore, there might be the some comment duplications.

[ajaust]

Looks good overall. One verification questions and otherwise nitpicks. Check if you want to address these, but feel free to ignore them. :)

[ajaust]

Nitpick:
Empty line missing above definition of value_format.

[Copilot]

Pull request overview

Copilot reviewed 18 out of 18 changed files in this pull request and generated 4 comments.

Comments suppressed due to low confidence (1)

lib/resdata/rd_kw_grdecl.cpp:12

• rd_kw_grdecl.cpp throws standard exceptions (std::invalid_argument, std::bad_alloc) but does not include the corresponding standard headers (<stdexcept> / <new>). Adding them explicitly avoids relying on transitive includes and prevents build failures on some compilers.

#include <cstring>
#include <cctype>
#include <optional>
#include <memory>

#include <ert/util/util.hpp>
#include <fmt/format.h>

#include <resdata/rd_kw.hpp>
#include <resdata/rd_type.hpp>
#include <resdata/rd_util.hpp>