[2.12.0] 2025-12-08

✨ Enhancements

• Updated SnapshotTracer to open the generated HTML report in a one-shot server, instead of opening the HTML file directly.
• Extended infinite-loop check to flag while loops whose conditions depend only on immutable variables and are not reassigned in the loop body.
• Added custom renderers for the PEP8 error codes: E204, E225, E231
• Added custom renderers for the PEP8 error codes: E271, E274, E502
• Updated the message format for Pycodestyle error messages to be more concise
• Added custom renderer for line-too-long to improve its error snippet to highlight the overflow segment instead of the entire line.
• Improved error message for error C0305 trailing-newlines and inserted a "DELETE" comment for each trailing newline.
• Added a solution to prevent possible large snippets created by the following errors: pylint error C0305, and pycodestyle errors E303, E304
• Added markdown rendering to display code in error messages
• Improved RI checking to raise a warning when a NameError is raised and the missing name matches an instance attribute, and is due to an omitted self. in the RI.
• Extended AccumulationTable class to support multiple loops in sequence within the same context manager
• Added a solution to prevent possible large snippets created by the render_generic function
• Support Python 3.14

💫 New checkers

Pylint checkers v4.0:

• break-in-finally

For more information on these checkers, please see the
Pylint release notes. Note that the above
list only contains the Pylint checkers enabled by default in PythonTA.

Custom checkers:

• unnecessary-f-string: Added new checker that checks f-string to see if it only consists of a single bare format expression that can be replaced with the string representation of that expression
• simplifiable-if: Added a new checker that checks if an if or elif branch only contains a single nested if statement with a single branch.

🐛 Bug fixes

• Fixed issue that caused PEP8 errors E301, E302, E303, E304, E305 and E306 to not render properly

🔧 Internal changes

• Added tests for node_printers.py functions rendering the PEP8 error messages: E101, E116, E124, E128, E201, E202
• Added tests for node_printers.py functions rendering the following PEP8 error codes: E221, E251, E261, E272, E273, E302, E305, E306
• Refactored node_printers.py by grouping repeated code in helper functions and grouping identical functions into a single functions to reduce code duplication
• Updated GitHub Actions workflow to Node 24
• Refactored custom renderers to accept config parameter to stay consistent with the added parameter for render-message
• Refactored setendings.py to rely primarily on Astroid/Python’s built-in end-location attributes, reducing the amount of custom parsing logic
• Fixed test_html_server.py tests to be compatible with Windows
• Updated conftest.py and test_black.py to be compatible with pytest v9, removing usage of some deprecated features.
• Updated tests in test_accumulation_table.py to cover multi-loop behavior and added new cases
• Updated to pylint v4.0 and astroid v4.0

[2.11.1] 2025-08-17

🐛 Bug fixes

• Fixed reports to only include config files when they have errors

[2.11.0] 2025-08-16

✨ Enhancements

• Support x in and x not in preconditions involving set(), list(), and tuple() function calls in the Z3 parser.
• Update the output-format configuration option to take reporter aliases rather than the plugin path.
• Integrated Watchdog to enable automatic re-checking of Python files when changes are detected.
• Added autoformat-options configuration option to let users specify command-line arguments to the Black formatting tool
• Update check_all and check_error functions to let users pass in typing.IO objects to the output argument
• Update the forbidden-io-function-checker to check functions from imported modules as well as methods (according to their qualified name)
• Update the forbidden-io-function-checker to flag aliases of forbidden functions
• Update how error messages are overridden such that section headers are no longer required within the config file
• Added presistent_server which recives the watch property changes through websockets and updates the HTML report
• Added optional on_verify_fail argument to check_all and check_error, allowing users to raise a ValueError and immediately stop execution when a file cannot be checked.
• Enhanced CFG generation to support match statements.
• Added the optional format argument to the AccumulationTable class, allowing users to select between csv or table formatted outputs.
• Added optional z3_enabled argument (default False) to generate_cfg, allowing users to enable z3 functionalities and providing extra safeguard to prevent z3 (and z3 related) imports from being executed when z3 is not enabled.
• Added a dark mode toggle with system detection for the html reporter
• Replaced icons on the html reporter using the heroicons library, adding hover effects
• Extended infinite-loop check to flag while loops with constant conditions and no exit statements (e.g.: return, break, raise, yield, sys.exit())
• Added command-line interface for CFG generation, allowing users to run python -m python_ta.cfg <file> with options for auto-open and visitor configuration
• Updated the color palette for the PythonTA web reporter to improve readability and visual hierarchy.
• Reduced shadow intensity, refined border opacity, and added subtle hover effects on interactive elements for the PythonTA web reporter to improve user experience.
• Aligned slider dropdown icons with the title text of errors in the web reporter to improve user experience
• Updated SnapshotTracer bundled webstepper version to v0.7.0
• Added a small margin to the topmost error instance card in the web reporter to prevent the top border from being cut off when the hover effect is activated
• Updated the error type text colors on the dark theme to be more consistent with that on the light theme
• Changed default MemoryViz version used by snapshot from "latest" to "0.7.0"

💫 New checkers

• infinite-loop: Provide an error message when a while loop never terminates, indicating an infinite loop.

🐛 Bug fixes

• Introduced the IDTracker class to track unique IDs in memory model diagrams across multiple snapshots.
• check_contracts no longer makes methods immediately enforce Representation Invariant checks when setting attributes of instances with the same type (one Node modifies another Node instance) and only checks RIs for these instances after the method returns.
• Fixed error in contracts where comments in docstring assertions are not removed while parsing
• Improved error message in patches/transforms.py where CFGVisitor is run
• Fixed a bug in AccumulationTable where loop variable names weren't being captured for all nested targets.
• Fixed a bug in the infinite-loop checker where function and method names were incorrectly included in the set of condition variables.
• Fixed "No Problems Detected" message colour in HTML report
• Fixed bug in SnapshotTracer output when using MemoryViz v0.7.0

🔧 Internal changes

• Refactored custom checker tests to group repeated tests using pytest.mark.parametrize.
• Dynamically loaded only the reporter specified in the configuration
• Added test case for check_all function ensuring proper behaviour when handling inputs in package notation.
• Improved get_valid_files_to_check function by removing unreachable code.
• Refactored test_check.py to use pytest.mark.parametrize annotation, improving test isolation and extracting inputs from test functions
• Added test case to test_check.py for better coverage of colour_messages_by_type
• Removed unused imports from python_ta module
• Wrapped type-only imports in if TYPE_CHECKING guards
• Refactored render_pep8_errors to use a dict that maps error codes to error functions instead of repeated conditional statements
• Added two test cases to test_accumulation_table.py to verify that AccumulationTable correctly extracts loop variables from nested tuple structures.
• Refactored condition_logic_checker.py, cfg_generator.py and graph.py by removing top-level z3 (and z3 related) imports and moving them inside of functions where needed.
• Wrapped type-only z3 (and z3 related) imports in a TYPE_CHECKING guard in condition_logic_checker.py, graph.py and cfg_generator.py.
• Added tests to improve coverage in condition_logic_checker.py, graph.py and cfg_generator.py, verifying behaviour in case of failed z3 (and z3 related) import via import patching.
• Added z3_enabled optional initializer argument (default False) to ControlFlowGraph class in graph.py and CFGVisitor class in visitor.py.
• Updated transforms.py to ensure the patched version of patch_ast_transforms dynamically reads the z3 option from linter config to reflect correct runtime setting.
• Simplified combined Z3 preconditions in set_function_def_z3_constraints using z3.simplify
• Refactored one_shot_server and persistent_server to allow for reuseablity.
• Removed old unused files
• Linked the contributions list (README.md) in the pull request template

[2.10.1] 2025-02-19

🐛 Bug fixes

• Fix import error when graphviz is not installed

[2.10.0] 2025-02-18

✨ Enhancements

• Added custom error message for comparison-with-callable
• Changed pyta-template-file argument to now resolve the file path relative to the CWD.
• Added a watch configuration option to the HTML reporter for persistent server mode.
• Added server-port configuration option to specify the port number to use when serving the PyTA HTML report.
• Added new checker option mypy-options in static-type-checker to let users override default mypy command-line arguments
• Added documentation for overriding messages
• Improved check_contracts error messages by ensuring a consistent format and phrasing
• Improved rendering of if/while/for syntax blocks in control flow graphs
• Ensured GraphViz-generated files have .gv extension
• Export generate_cfg from python_ta.cfg
• Move check_all configuration info to logging DEBUG level (was INFO)
• Update list of "error" checks

💫 New checkers

• redundant-condition: Provide error message when a conditional statement within a function is guaranteed true. This checker requires z3 option to be turned on.
• impossible-condition: Provide error message when a conditional statement within a function is guaranteed false. This checker requires z3 option to be turned on.
• incompatible-argument-type: Provide an error message when a function argument has an incompatible type.
• incompatible-assignment: Provide an error message when there is an incompatible assignment.
• list-item-type-mismatch: Provide an error message when a list item has an incompatible type.
• unsupported-operand-types: Provide an error message when an operation is attempted between incompatible types.
• union-attr-error: Provide an error message when accessing an attribute that may not exist on a Union type.
• dict-item-type-mismatch: Provide an error message when a dictionary entry has an incompatible key or value type.

🐛 Bug fixes

• Fixed issue in static-type-checker such that mypy no longer checks imported modules in the file being checked
• Fixed issue in autoformat where the default max-line-length value was not used
• Fixed issue in contract-checking new_setattr where an instance attribute was not always reset when reassigning it to an invalid value
• Fixed issue in AccumulationTable where accumulation expressions could not refer to loop variables
• Fixed issue in snapshot where some imported objects were being included in the output
• Fixed issue in snapshot where None was not being rendered in SVG correctly

🔧 Internal changes

• Configured CI tests to run on environments with and without z3 dependency.
• Refactored script.js to avoid using jQuery, and instead use vanilla Javascript functionality.
• Configured CI to upload coverage report for both base and z3 test environments
• Remove unnecessary calls to node.stream() in raw file checkers (pycodestyle and static type checkers)

[2.9.2] 2025-01-16

🐛 Bug fixes

• Ignore annotation-only assignment statements in redundant-assignment check

[2.9.1] 2024-12-09

🐛 Bug fixes

• Added python_ta/debug/webstepper to project MANIFEST.in

[2.9.0] 2024-12-09

✨ Enhancements

• Added include_frames filter to snapshot
• Added exclude_frames filter to snapshot
• Added exclude_vars filter to snapshot
• Added new python_ta.debug module with an SnapshotTracer context manager for generating memory models
• Added z3 option to inconsistent-or-missing-returns, redundant-assignment, and possibly-undefined checkers to only check for feasible code blocks based on edge z3 constraints
• Included the name of redundant variable in E9959 redundant-assignment message
• Update to pylint v3.3 and and astroid v3.3. This added support for Python 3.13 and dropped support for Python 3.8. (No new checkers are enabled by default.)
• Added a STRICT_NUMERIC_TYPES configuration to python_ta.contracts allowing to enable/disable stricter type checking of numeric types
• Added integration with MemoryViz Webstepper
• Added z3 option to one-iteration-checker to only check for feasible code blocks based on edge z3 constraints
• Added reporting for errors raised by custom transforms (Z3Visitor, CFGVisitor)
• Ensured SnapshotTracer does not include the _trace_func stack frame
• Enabled SnapshotTracer to create its output_directory argument if it doesn't already exist
• Changed SnapshotTracer's Webstepper code line number to align with the source code line number

💫 New checkers

• unmentioned-parameter: Provide error message when a function parameter is not mentioned by name in the function's docstring. By default, this checker is disabled.

🐛 Bug fixes

• Fixed issue where snapshot errors on unserializable values
• Fixed issue within Snapshot.py where the memory_viz_version parameter was not respected
• Fixed issue where parallel assignment statements and assignment to multiple targets were not checked by redundant_assignment_checker
• Fixed issue where annotated assignment statements were not checked by redundant_assignment_checker
• Fixed issue where empty preconditions were preventing CFGs from being generated
• Added strict numeric type checking to enforce type distinctions across the entire numeric hierarchy, including complex numbers.
• Added strict type checking support for nested and union types (e.g., list[int], dict[float, int], Union[int, float])
• Fixed issue where CFG edges from loop body to loop condition block was ignored during augmenting edge z3 constraints
• Fixed issue in one-iteration-checker where the message was not correctly reported for while loops when z3 option is on
• Fixed crash when z3-solver is not installed
• Fixed crash when an inline comment had no spaces after the #

🔧 Internal changes

• Renamed ExprWrapper class to Z3Parser
• Renamed ExprWrapper module to z3_parser and moved it to new directory python_ta.z3
• Removed node attribute for Z3Parser
• Renamed reduce method of Z3Parser to parse
• Renamed test_expr_wrapper to test_z3_parser
• Added is_feasible attribute for CFGEdge and implemented update to edge feasibility based on lists of Z3 constraints
• Refactored codebase to use modern type annotations. Replaced List with list, Dict with dict, Set with set, and Tuple with tuple
• Checked for variable reassignment in AugAssign and AnnAssign node in parsing edge Z3 constraints
• Rendered logically infeasible control flow graph edges in light grey
• Modified test_snapshot_to_json_sets_primitive for Python 3.8 compatibility
• Added unit tests for one_iteration_checker
• Added mock webbrowser.open in tests to prevent browser tabs and HTTP requests during python_ta.check_all() executions.
• Added pytest-mock as a development dependency
• Make test_snapshot.py::test_snapshot_serializes_unserializable_value able to run on Windows.
• Added GitHub Action workflow for automatically publishing releases to PyPI
• Update SnapshotTracer tests to use memory-viz@0.5.0 and prevent browser from opening
• Updated bundled webstepper version and removed source map, and excluded the bundle from prettier pre-commit check

[2.8.1] 2024-08-19

🐛 Bug fixes

• Fix loading of setendings plugin when z3-solver is not installed

[2.8.0] 2024-08-19

WARNING: this release assumes that the z3-solver Python library is installed. Users are strongly encouraged to install v2.8.1 instead.

✨ Enhancements

• Add new boolean configuration allow-local-imports to allow for local imports
• Extended the snasphot function to include the relevant variables defined at the top level (global variables).
• Include the pycodestyle error code to the error message for PEP8 style errors
• Added date and time display to PlainReporter and ColorReporter
• Allowed specifying allowed names in configurations allowed-import-modules and extra-imports instead of just modules
• Improved error display for pycodestyle (E9989) errors E123, E203, E222, E226, and E262
• Added the configuration option to ignore naming convention violations (C9103 and C9104) for names matching the provided regular expression.
• Update to pylint v3.1 and and astroid v3.1
• Stored actual AST condition node in edges leading out of If/While blocks in generated control flow graphs.
• Stored valid Python function preconditions in initial edge to function code in generated function control flow graphs.
• Report warning when control flow graph creation encounters a syntax error related to control flow
• Added autoformat option that runs black formatting tool to python_ta.check_all()
• Extended the snapshot function to optionally generate a svg of the snapshot using MemoryViz when save parameter is true.

💫 New checkers

Pylint checkers v3.1:

• use-yield-from
• deprecated-attribute

For more information on these checkers, please see the
Pylint release notes. Note that the above
list only contains the Pylint checkers enabled by default in PythonTA.

Custom checkers:

• inconsistent-returns and missing-return-statement: Provide clearer error messages when reporting missing return statements. This replaces pylint's R1710 check.

🐛 Bug fixes

• Fixed issue with error message of C0410 by reformating it to properly fit with the list of modules imported that are provided to it
• Fixed bug where _ was marked as a built-in when running PythonTA after running doctest
• Fixed issue where annotated constant variable assignment was not considered as permissible top level code and triggered error E9992
• Fixed issue where top level class attribute assignment was considered as permissible top level code
• Fixed issue where check_contracts fails silently when function preconditions contain precondition violations, and when a representation invariant contains a call to a top-level function (not built-in or imported library).
• Fixed issue where methods called in representation invariants lead to infinite recursion.
• Fixed issue where PossiblyUndefinedChecker raised an error if the control flow graph was invalid due to syntax error

🔧 Internal changes

• Updated changelog and pull request template formats
• Added unit tests for PEP8 errors E115, E122, E125, E127, E129, E131 for PycodestyleChecker
• Added unit tests for PEP8 errors E223, E224, E227, E228, E265 for PycodestyleChecker
• Refactored test_check_on_dir in test_check.py module to test on sample_dir, a subset of examples
• Added unit test test_examples_files_pyta in test_examples.py to check every file in examples with PythonTA
• Added unit tests for PEP8 errors E266, E275, E301, E303, E304 for PycodestyleChecker
• Moved tests related to __main__.py from test_check.py to test_main.py
• Added more unit tests to test_main.py to increase coverage of __main__.py to 100%
• Updated README.md to reflect updated folder structure
• Added unit test test_pycodestyle_errors_pyta in test_examples.py to check every file in e9989_pycodestyle with PythonTA for PEP8 errors
• Parametrized tests for PycodestyleChecker
• Moved tests related to snapshot.py out of test_accumulation_table.py and into new module test_snapshot.py
• Updated GitHub Action tests to avoid running test_accumulation_table.py and test_recursion_table.py with coverage and add verbose output for debug testing
• Allowed GitHub Action tests to run on all pull requests, including drafts
• Updated dependencies for GitHub Actions to use the latest versions
• Updated dependabot configuration to auto-update dependencies for GitHub Actions in the future
• Updated usage messages in examples/sample_usage/ of draw_cfg.py and print_ast.py to be accurate on all operating systems
• Removed redundant line from tests/test_examples.py
• Fixed minor typo in an error message in python_ta/cfg/visitor.py
• Updated ExprWrapper to support set/list/tuple literals and in/not in operators
• Updated snapshot.py and test_snapshot.py to align with MemoryViz 0.2.0 updates
• Updated ExprWrapper to support string variables and ==, in/not in, indexing and slicing operators
• Added protected _z3_vars attribute to ControlFlowGraph to store variables to be used in Z3 solver
• Removed unused imports from python_ta/cfg/graph.py
• Extended functionality of ExprWrapper class to include function definitions' arguments and name assignments
• Added z3 to dependencies installed as part of the docs job in the GitHub Actions workflow
• Added tests to maintain/increase coverage of visitor.py, graph.py, and ExprWrapper.py
• Removed deprecated and redundant future argument from node.frame() call in invalid_name_checker.py
• Updated pylint to v3.2.6 and astroid to v3.2.4 (no new checks were enabled by default)
• Excluded node_modules/ folder from package autodiscovery
• Updated graph.py to augment control flow graph edges with z3 constraints
• Added support for the != operator and replaced dictionary indexing with .get in ExprWrapper.
• Refactored Z3Visitor to use safe_infer() instead of inferred() and added handling of AstroidError.
• Add negate attribute to CFGEdge