Release 0.19.0

Added

• Add public get_data_type(calctype) and ProgramInput.from_spec() helpers for parsers and execution packages.

Changed

• Every model now writes the installed qcdata_version to JSON/YAML/TOML; nested models are stamped too. Loading accepts an existing stamp, and resaving replaces it with the current package version. XYZ structures include a version comment; QCSchema exports exclude qcdata-specific stamps.

• Default save() and json_dumps() use exclude_unset=True for compact files, retaining explicitly supplied values and computed version stamps. Pass exclude_unset=False to include unset/default-valued fields. The JSON helper handles individual models and lists consistently, including paths. Models retain shallow freezing; direct container mutation is unsupported and the supported update workflow is dump/edit/validate.

• JSON schemas describe scientific array dimensions correctly. NumPy energy defaults use factories, eliminating non-serializable-default schema warnings.

• QCSchema conversion preserves source extras and additional producer metadata without claiming QCEngine produced every result. Completed public data/identifier exports and corrected viewer documentation.

• The temporary .data compatibility property and legacy input key are scheduled for removal in the next major release after this one.

• Breaking: result types now follow the input contract on both success and failure. FileInput requires FileData; structured inputs require their corresponding scientific data type even for empty failures. Empty payloads deserialize using the input calculation type, including in nested trajectories.

• Empty optimization final values return None; empty scan trajectories are supported. Scan structures preserve missing points as None, and XYZ export rejects points without a final structure. Visualization handles empty failed outputs.

• Breaking: renamed execution fields to host_cpu and host_mem_gib (fractional GiB supported), without compatibility aliases. Removed the prototype Structure.swap_indices method.

• Updated qcinf to >=0.4.1, removing the qcio dependency and obsolete structure-type workaround.

• ProgramOutput.results is now the canonical scientific payload field and serialized key. Scientific models retain their Data names. .data and legacy "data" inputs remain temporarily supported with FutureWarning; providing both field names is invalid.

• Breaking: removed the Results, *Results, and Molecule aliases, qcdata.models.results and qcio import shims, molecule= and ids= constructor compatibility, stdout/files forwarding, deprecated output convenience properties, and helpers moved to qcinf. Use canonical APIs directly.

• Breaking: result payloads now inherit from FileData and require Provenance containing program identity and optional version. ProgramOutput.provenance is replaced by execution: ExecutionInfo, defaulting to ExecutionInfo() when runtime details are unknown. Migrate serialized outputs and each trajectory entry by moving producer identity into results.provenance and runtime fields into execution.

• Breaking: all inputs now require program. Replaced ProgramArgs, ProgramArgsSub, and DualProgramInput with recursive ProgramSpec and structure-bound ProgramInput. Migrate subprogram / subprogram_args to subprograms, giving each child its own program and calctype; sibling calculation types must be unique. model is optional and remains a separate Model object. Existing serialized inputs require the same migration.

• Added immediate-child lookup with get_subprogram(calctype), recursive visualization details, and an explicit error when converting a model-free input to QCSchema AtomicInput.

What's Changed

• • feat!: redesign calculation inputs, results, and execution metadata by @coltonbh in #106

Full Changelog: 0.18.1...0.19.0