* use f-strings
* inline immediately returned variables
* simplify comprehension
* use list literals
* lift return statements into control flow blocks
* other pure refactorings
* remove passthrough function
* use a ternary when it improves readability
* use __getitem__ for regex match groups; introduced in Python 3.6
* fix changed comments
* revert one change
* support single element IfPresentPlaceholders that contain a primitive placeholder
* block list then and else_ inside concat
* support single element IfPresent in v1
* clean up typing
* skip loading batch_predict_job yaml
* simplify placeholders
* update placeholders_test.py
* update structures to use placeholders correctly
* update use of placeholders elsewhere in codebase
* clean up
* move placeholder type checking logic to PipelineTask to prevent v1 load breaks
* clean up
* update docstrings
* make to_dict and to_string private methods
* revert unnecessary change to tests
* improve type safety of code
* prefix module-level constant with underscore
* remove dependency of deprecated on v2
* use new artifact identification logic
* add custom artifact type compiler test
* compile schema_version from non-kfp artifacts
* update tests
* add importer to compiler test
* update golden snapshots
* fix type checking code
* undo executor_test diff
* remove gcpc types compiler test
* add compilation test comment
* update google artifact handling
* update compiler test
* only permit system. and google. artifact types; add tests
* update compiler test
* simplify type checking logic
* use bundled artifact types in PipelineArtifactChannel
* raise error on unknown v1 input or output
* add type utils and move functions
* add type utils tests
* remove schema_version from inputspec and outputspec
* update artifact proto creation and tests
* propogate bundled artifact type string changes throughout sdk
* update golden snapshot
* remove unused v1 compat and tests
* update type checking and tests to validate schema_version using semantic versioning
* update importer sample
* update test data config
* update test_data config
* clean up sample
* clean up sample
* add compiler test pipeline with multiple exit handlers
* remove blocker of multiple exit handlers
* move exit handler builder logic to pipeline_spec_builder
* build all exit handlers per pipeline
* add compiler test with IR inspection
* prevent usage of cross-pipeline after
* test cross-pipeline after is prevented
* update existing task dependency logic and tests
* add v2 sample test
* remove cross-pipeline .after
* prevent cross-dag data dependency for dsl features
* add compiler test pipeline with nested exit handlers
* add support for nested exit handlers
* clean up pipeline with nested exit handlers
* remove sample with multiple exit handlers
* remove compiler test with nested exit handlers
* add compilation guard against nested exit handlers in subdag
* update release notes
* add module-level docstrings
* update compiler docstrings
* update registry module docstrings
* add BaseComponent and children to public api, but discourage use
* update artifact docstrings and type annotations
* update dsl docstrings
* update client docstrings
* clean up kfp.__init__
* add dsl placeholder docstrings
* many more docstring updates
* document type aliases in dsl module
* move placeholders to placeholders module; implement if-present and concat placeholders
* update module name and method names throughout codebase
* rename placeholder abc
* add back compat support for CEL-style concat string
* add copyright
* add docstrings; clean up
* remove duplicate code
* clean up relevant files
* use context manager for temporary directory cleanup
* add component compilation methods
* add component compilation tests
* add more complete pipeline_func argument handling
* use context manager for handling type check mode
* improve checks on inputs for component compilation
* correct pipeline name for primitive component IR
* simplify component compilation logic
* extract compiler methods
* move compiler helpers to helpers file to avoid circular imports
* remove underscore prefix from functions in hidden module
* move helpers tests to helper_test module
* put to_pipeline_spec on ComponentSpec
* fix inputs reference
* use same naming regex for pipelines and components
* permit compilation of all BaseComponent subclasses
* clean up docstrings
* merge compiler.helpers into pipeline_spec_builder
* modify docstrings; refactor
* modify docstring
Chen Sun
Connor McCarthy
JOCSTAA
Scott_Xu
Yaqi Ji