Make rd_file use pybind

[eivindjahren]

This fixes a bug with the report_steps and num_report_steps
methods, which would throw KeyError on files without "SEQNUM".
It now returns []/0 as documented.

The has_kw and report_dates functions had imprecise docstrings,
which were updated.

In several places, changes from int to size_t had to be propagated to
avoid narrowing.

Also changes the return value of iget_restart_sim_days from sentinels
to raising IndexError when the index is too large.

Also changes has_sim_time(t) to just be bool(find_sim_time(t)). Before
there was a discrepancy between has_sim_time and find_sim_time where
find_sim_time work correctly on non-unified files, but has_sim_time did not.

[Copilot]

Pull request overview

This PR migrates the Python ResdataFile implementation from the legacy cwrap-based rd_file.py wrapper to a pybind11-based extension module, while also tightening index-file validation/error behavior and updating the C++ API to use FileType (enum class) and size_t where appropriate. It also fixes documented behavior for report_steps / num_report_steps() on non-restart files and expands test coverage around index corruption/truncation cases.

Changes:

• Replace the Python rd_file.py wrapper with a pybind11 module (lib/resdata/rd_file_pybind.cpp) and add type stubs (python/resdata/resfile/rd_file.pyi).
• Introduce pybind bindings for FileMode + new FileType enum via _rd_util, and update codebase usage from old rd_file_enum constants to FileType.
• Rework index serialization/validation and add extensive tests for invalid index scenarios and non-restart-file restart APIs.

Reviewed changes

Copilot reviewed 71 out of 71 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
tests/rd_tests/test_rd_file.py	Adds/adjusts Python tests for index filename storage, index corruption handling, and non-restart-file report_* behavior.
python/resdata/resfile/rd_file.pyi	New typing stub for the pybind-provided ResdataFile API.
python/resdata/resfile/rd_file.py	Removes the legacy cwrap-based Python implementation (module now provided by pybind).
python/resdata/resfile/_open_rd_file.py	Reintroduces open_rd_file() as a small Python context-manager wrapper around ResdataFile.
python/resdata/resfile/init.py	Updates exports to import open_rd_file from the new helper module and ResdataFile from the pybind module.
python/resdata/rd_util.py	Switches FileMode/FileType and _get_file_type to the new _rd_util pybind module and adjusts typing.
python/resdata/_rd_util.pyi	Extends the stub to export FileType and _get_file_type() along with FileMode.
lib/util/util.cpp	Removes legacy util_fwrite_string / util_fread_alloc_string helpers (index I/O moved to stream-based code).
lib/util/stringlist.cpp	Updates a comment to reflect C++ sources (vector.cpp/util.cpp) rather than C files.
lib/tests/test_well_info.cpp	Migrates tests from open_rd_file/C API to rd::File::open() and get_global_view().
lib/tests/test_rd_sum.cpp	Migrates summary tests to rd::File::open() and C++ member calls (get_kw, write, etc.).
lib/tests/test_rd_kw.cpp	Updates overflow test to use iostreams and expects std::length_error from FileKW::read().
lib/tests/test_rd_file_kw.cpp	Switches index header read/write tests from FILE* to std::ifstream/ofstream with exceptions enabled.
lib/tests/test_geertsma.cpp	Migrates various uses to rd::File::open() and get_global_view().
lib/resdata/well_state.cpp	Updates comments and aligns assumptions with the FileView/C++ API naming.
lib/resdata/well_pybind.cpp	Updates load_rstfile dispatch to accept rd::File instances directly; improves type error message.
lib/resdata/well_info.cpp	Migrates well-loading paths from rd_file_type* to rd::File* and uses FileType.
lib/resdata/tests/well_ts.cpp	Updates rd_select_filelist usage to FileType::RESTART.
lib/resdata/tests/well_state_load.cpp	Migrates to rd::File::open() / get_global_view() and C++ has_kw().
lib/resdata/tests/well_state_load_missing_RSEG.cpp	Migrates to rd::File::open() / get_global_view().
lib/resdata/tests/well_segment_load.cpp	Migrates keyword lookups to rd::File::get_kw() and view accessors.
lib/resdata/tests/well_dualp.cpp	Migrates to rd::File::open() and C++ keyword access.
lib/resdata/tests/well_conn_CF.cpp	Migrates to rd::File::open() and C++ keyword access.
lib/resdata/tests/test_rd_file.cpp	Migrates to rd::File::open() and C++ save_kw() / size() usage; switches counts to size_t.
lib/resdata/tests/test_rd_file_index.cpp	Migrates fast-open/index tests to exceptions (rd::File::fast_open) and size_t.
lib/resdata/tests/rdxx_kw.cpp	Migrates keyword access to rd::File::get_kw().
lib/resdata/tests/rd_rsthead.cpp	Migrates to rd::File::open() and FileType checks.
lib/resdata/tests/rd_restart_test.cpp	Migrates to rd::File::open() + find_sim_time() API (now optional).
lib/resdata/tests/rd_nnc_test.cpp	Migrates to rd::File::open() / num_named_kw() and new blockview() overload.
lib/resdata/tests/rd_lgr_test.cpp	Migrates to rd::File::open() / num_named_kw().
lib/resdata/tests/rd_grid_volume.cpp	Migrates filename selection and file open to FileType + rd::File::open().
lib/resdata/tests/rd_grid_init_fwrite.cpp	Migrates to rd::File::open() / get_kw().
lib/resdata/tests/rd_grid_export.cpp	Migrates to rd::File::open() / has_kw() / get_kw().
lib/resdata/tests/rd_grid_dx_dy_dz.cpp	Migrates to rd::File::open() / get_kw().
lib/resdata/tests/rd_filenames.cpp	Migrates filename/type tests to FileType and updates includes.
lib/resdata/tests/rd_file_equinor.cpp	Removes close-stream/load-all legacy tests and migrates writable path to rd::File.
lib/resdata/tests/rd_dualp.cpp	Migrates to FileType + rd::File::open() / get_kw().
lib/resdata/tests/rd_coarse_test.cpp	Migrates to FileType + rd::File::open() / get_kw().
lib/resdata/rd_util.cpp	Replaces legacy rd_file_enum with FileType throughout and updates related APIs.
lib/resdata/rd_util_pybind.cpp	Adds _rd_util pybind module for FileMode, FileType, and _get_file_type().
lib/resdata/rd_unsmry_loader.cpp	Migrates UNSMRY loading to rd::File::open() and C++ methods.
lib/resdata/rd_sum.cpp	Migrates summary-file type branching and filename selection to FileType.
lib/resdata/rd_sum_file_data.cpp	Migrates file checks and summary loading to rd::File and FileType.
lib/resdata/rd_sum_data.cpp	Migrates unified summary filename selection to FileType.
lib/resdata/rd_subsidence.cpp	Migrates INIT file handle from rd_file_type* to rd::File* and uses get_kw().
lib/resdata/rd_subsidence_pybind.cpp	Updates binding to accept rd::File* directly for INIT file parameter.
lib/resdata/rd_smspec.cpp	Migrates header parsing to rd::File and updates keyword lookup/aliases to C++ API.
lib/resdata/rd_grid.cpp	Migrates many internals to rd::File/FileType and replaces several int indices with size_t.
lib/resdata/rd_grav.cpp	Migrates INIT file handle type to rd::File*, introduces helpers for phases/version reading, and improves errors.
lib/resdata/rd_grav_pybind.cpp	Updates binding to accept rd::File* directly for INIT file parameter.
lib/resdata/rd_grav_common.cpp	Migrates keyword access to rd::File C++ methods.
lib/resdata/rd_file.cpp	Replaces legacy rd_file_type C API with rd::File implementation, stream-based index I/O, and exception-based fast-open validation.
lib/resdata/rd_file_view.cpp	Switches index serialization to iostreams, migrates to size_t/optional APIs, and tightens index read error handling.
lib/resdata/rd_file_pybind.cpp	New pybind11 module implementing ResdataFile directly in C++ (replacing the old _file bridge).
lib/resdata/rd_file_kw.cpp	Migrates FileKW index header I/O to std::istream/std::ostream and adds allocation guards via reserve().
lib/resdata/file_mode_pybind.cpp	Removes the old standalone _file_mode pybind module (replaced by _rd_util).
lib/resdata/cwrap_pybind.cpp	Removes from_cwrap<rd_file_type> support now that ResdataFile is no longer a cwrap object.
lib/private-include/detail/resdata/rd_unsmry_loader.hpp	Updates stored file handle type to std::unique_ptr<rd::File>.
lib/private-include/detail/resdata/rd_sum_file_data.hpp	Updates check_file signature to accept rd::File*.
lib/include/resdata/well/well_info.hpp	Updates WellInfo APIs to accept rd::File* instead of rd_file_type*.
lib/include/resdata/rd_util.hpp	Replaces rd_file_enum typedef with enum class FileType and updates function signatures.
lib/include/resdata/rd_subsidence.hpp	Updates API to accept const rd::File* for INIT file.
lib/include/resdata/rd_grav.hpp	Updates API to accept const rd::File* for INIT file.
lib/include/resdata/rd_grav_common.hpp	Updates API to accept const rd::File* for INIT file.
lib/include/resdata/rd_file.hpp	Replaces the legacy C API declarations with the new rd::File class interface.
lib/include/resdata/rd_file_view.hpp	Updates FileView index/container types to size_t/optional and migrates I/O to streams.
lib/include/resdata/rd_file_kw.hpp	Updates FileKW header read/write APIs to use iostreams.
lib/include/ert/util/util.hpp	Removes declarations for the deleted util_fwrite_string / util_fread_alloc_string.
lib/CMakeLists.txt	Renames the rd-file pybind module to rd_file and replaces _file_mode with _rd_util; adjusts test executable list.
applications/resdata/rd_unpack.cpp	Migrates unpack tool to FileType + rd::File C++ API and size_t.
applications/resdata/rd_pack.cpp	Migrates pack tool to FileType + rd::File C++ API.

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[eivindjahren]

This is existing behavior and we need binary compatible files so we cannot change this.

[Copilot]

Pull request overview

Copilot reviewed 71 out of 71 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 77 out of 78 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 77 out of 78 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 72 out of 72 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 72 out of 72 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (1)

lib/resdata/rd_file_view.cpp:313

• The find_sim_time doc comment refers to calling iselect_rstblock() for LGR handling, but there is no such function in this codebase (and the surrounding API no longer exposes a block-selection mechanism). This makes the guidance misleading for users trying to interpret the returned index on LGR files.

Each report step only has one occurence of SEQNUM, but one INTEHEAD
for each LGR; i.e. one should call iselect_rstblock() prior to
calling this function. */

[Copilot]

Pull request overview

Copilot reviewed 72 out of 72 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 72 out of 72 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 72 out of 72 changed files in this pull request and generated no new comments.