pypi / configargparse
configargparse
What changed in configargparse 1, from its official release notes, upgrade guides and advisories. Sources checked 2026-10-18.
3 breaking1 new APIs and options2 behavior and defaults1 tooling2 fixes and other
See which of these apply to your code, ranked, in your agent:
npx @unstale/cli initconfigargparse 19 changes
Breaking changes 3
Values from higher-priority sources now override conflicting values in mutually exclusive groups; conflicts within one source still raise an error.
A parser missing an optional dependency now raises this exception, a subclass of ConfigFileParserException, instead of being silently skipped.
Values containing newlines are rejected when writing out a config file, rather than being written out as separate keys.
New APIs and options 1
The toml extra declares the optional dependency used for TOML support, including writing config files on every Python version.
Behavior and default changes 2
CompositeConfigParser warns with the parser name and installation instructions, then continues down the parser chain.
TOML config files can now be read from binary streams on Python versions before 3.11.
Tooling 1
Python 3.14 is now supported and tested in CI.
Fixes and other changes 2
Arguments declared with a custom argparse Action and nargs can now be set from a config file.
Config file and environment variable values can no longer trigger writing out a config file.