1.1.0.rc1 (2021-05-13)

This is the biggest Hydra release yet.

Highlights

• OmegaConf 2.1 supports relative interpolations, nested interpolations, more powerful resolvers and better compatibility with plain Python dict and list.
• Recursive defaults list: Every config can now have a Defaults List.
• Recursive instantiation: When instantiating objects using the instantiate API, nested defined objects are instantiated automatically.

There have also been many bug fixes and performance improvements, as well of as some breaking changes - both in Hydra and in OmegaConf.
Please check the API changes and deprecation sections in these release notes and in the OmegaConf release notes.

Features

General enhancements

• Upgrade to OmegaConf 2.1. Please check the release notes for it (#1426)
• Support for Python 3.9. (#1062)
• Improve performance of config composition in a benchmark by 64% (#1328)
• Allow @, $ and ? symbols in unquoted values in overrides (#1074, #1437, #1597)
• Add a --resolve flag that can be used with the --cfg flag to resolve interpolations before the config is printed. (#1585)
• It is now possible to disable Hydra's logging configuration (#1130)
• Support for Zsh tab completion (#347)
• Support for force-add of config values via ++key=value (force-add overrides if the value exists and adds it otherwise) (#1049)

Config composition enhancements

• Support for Defaults List in any config (Recursive relative defaults) (#1170)
• Composition order of a config with a Defaults List can be specified with the _self_ keyword. (#326)
• Support for configuring the config search path from the primary config (#274)
• Add support for selecting multiple configs from the same Config Group (#499)
• Final choices of defaults list are retained in the dictionary hydra.runtime.choices (#956)

Object Instantiation enhancements

• Support for recursive instantiation with hydra.utils.instantiate() (#566)
• Instantiate now fully supports positional arguments (#1432)
• Support for converting parameters to primitive containers during instantiation (#1015)
• It is now possible to override the _target_ of instantiation with a Python type or a string (#1017)

API Change (Renames, deprecations and removals)

General changes

• Default composition order change, see this for details (#1217)
• Remove deprecated strict flag from @hydra.main and the Compose API (#1010)
• Passing a config name as config_path to @hydra.main is now an error (#1010)
• Promote hydra.experimental.{compose,initialize,initialize_config_dir,initialize_config_module} out from the hydra.experimental module to the hydra module. (#1030)
• The override grammar now requires that, in quoted strings, any sequence of \ preceding a quote (either an escaped quote, or the closing quote) must be escaped (#1600)

Instantiate changes

• Instantiate is now recursive by default, use _recursive_=False to disable recursive instantiation. (#566)
• Deprecated TargetConf, you should no longer be extending or annotating with it (#1010)
• Remove ObjectConf and deprecated params support that was deprecated in Hydra 1.0 (#1010)

Plugins API changes

• HydraContext required in run_job, Launcher and Sweeper's setup methods, see issue for details (#1498)
• ConfigSourcePlugins needs to be modified to support recursive defaults, see link for details (#1080)

Bug Fixes

• Hydra no longer erroneously changes the USER environment variable in pytest unit tests once installed (#1059)
• Fix a bug where Structured Config has a field like list : Optional[List[int]] = None (#1117)
• No longer modifies exception stack trace when running under a debugger (#1237)
• hydra.job.{id,num} are now properly passed to jobs in multirun (#1270)
• Add support for %f directive (microseconds) to the ${now:PATTERN} resolver (#1287)
• Fixed a bug where tab completion did not work if the Defaults List had a missing (???) item. (#1381)
• Fix + overrides to properly insert new values into Structured Configs. (#1515)
• Fix edge cases where using the command line to set a key to a value containing a string ending with a backslash could crash (#1600)

Plugins

• Add Optuna Sweeper plugin

Improved Documentation

• New Defaults List page (#1170)
• New Extending Configs pattern (#1170)
• Major updates to the Packages page (#1170)
• New Configuring Experiments pattern (#1170)