Drop el8, case-insensitive context, adjust decision callback

Highlights

• Case-insensitive context matching
• Drop support for el-8 and python-3.6
• Implement custom decision_callback in adjust()

Full Changelog

• Allow case-insensitive context matching
• Move the copr repository to the teemtee group
• Fix missing file require for unit tests
• Add callback to adjust() to make it observable by callers
• Drop support for el-8 and python-3.6
• Fix docs building on readthedocs
• Install yq needed for tmt integration tests
• Include srpm_build_deps in the packit config
• Remove metadata from Packit config
• Add missing build job to Packit config
• Update pre-commit checks to the latest versions
• Require fmf in tests, remove obsolete coverage
• Fix a typo in the merging minus sign documentation

Retry if shallow clone didn't work

Single bugfix:

• Retry if shallow clone fails

Context (when optional, true/false); Select by source

Changes:

• Shallow git clone if no reference is used
• Select by the source of object
• Enable the flake8 check, fix detected issues
• Make when in adjust optional, add true|false expr.
• Version as fmf flag and module attribute

Directive for disabling inheritance; Schema validation

Features and bug fixes:

• Implement a directive for disabling inheritance
• Add support for prepending items during merging
• Explicitly convert context value to string
• Workaround s390x ruamel read issue
• Support reference schemas in validation function
• Add JSON Schema validation method
• Fixes blocking with symbolic link loops
• Use a better way to detect the default git branch
• Add unit tests for comma operator in context rules
• Add examples demonstrating the context syntax

Repo maintenance:

• Create commit builds from the main branch
• Enable epel-9 for copr builds and testing

Migrate to ruamel.yaml, drop Python 2 support

• Migrate yaml parsing to ruamel.yaml
• Drop support for Python 2
• Add extra requires and enable readthedocs config (#143)
• Filter accept value with a colon
• Adjust style to fix issues revealed by pre-commit
• Enable pre-commit, update contribution docs
• Disable integration testing with tmt for centos-7

Keep adjust rules, improve their evaluation, support empty files...

• Add support for empty files and virtual nodes
• Change outcome of CannotDecide operations
• Enable copr builds from master for epel-7 as well
• Define dict method to get child or data item
• Keep original adjust rules when adjusting nodes
• Use a deep copy when storing raw node data
• Fix warnings in pytest

Cache improvements, copy nodes, modify metadata...

• Implement the new 'fmf clean' command
• Functions to manipulate cache
• Fetch the whole tree using utils.fetch_tree()
• Raise FileException on duplicate YAML keys
• Allow to set desired cache location
• Adjust support for storing modified data to disk
• Add support for storing modified metadata to disk
• Prevent exploring tests in the tmp directory
• Simplify special distro comparison examples
• Store command output in run(), fetch() exceptions
• Use filelock for locking, expand test coverage
• Adjust locking for Tree.node() and utils.fetch()
• Use locking to checkout/read tree
• Enable integration testing with tmt, some cleanup
• Implement a new method copy() for cloning nodes
• Adjust fetch() with custom destination and env
• Support calls fetch(destination, env) and run(env)
• Use the origin default branch instead of master
• Store commit hash if the tree is under a git repo

Recursive merging, continue default, special comparisons...

• Adjust context docs, fix typos, style cleanup
• Left vs Right side in Context matches
• Simplify deep merging, adjust test suite a bit
• Implement recursive merging of data
• Remove the duplicate build job from packit config
• Adjust 'make test' to work under virtualenv
• Update the adjust continue key default to True

Adjusting metadata based on context

• Enable copr builds from master, simplify config
• Adjust documentation for the new Context class
• Add documentation for the new Context class
• Add a new Tree.adjust() method for handling rules
• Context: Better operator names, comments
• Adjust the new Context implementation
• Context implementation

Fix cache issue in utils.fetch

0.12

Release fmf-0.12