Package: vulture
Vulture - Find dead codeVulture finds unused code in Python programs. This is useful for
cleaning up and finding errors in large code bases. If you run Vulture
on both your library and test suite you can find untested code.Due to Python's dynamic nature, static code analyzers like Vulture are
likely to miss some dead code. Also, code that is only called implicitly
may be reported as unused. Nonetheless, Vulture can be a very helpful
tool for higher code quality.Featuresfast: uses static code analysistested: tests itself and has complete test coveragecomplements pyflakes and has the same output syntaxsorts unused classes and functions by size with--sort-by-sizeInstallation$ pip install vultureUsage$ vulture myscript.py  # or
$ python3 -m vulture myscript.py
$ vulture myscript.py mypackage/
$ vulture myscript.py --min-confidence 100  # Only report 100% dead code.The provided arguments may be Python files or directories. For each
directory Vulture analyzes all contained*.pyfiles.After you have found and deleted dead code, run Vulture again, because
it may discover more dead code.Types of unused codeIn addition to finding unused functions, classes, etc., Vulture can detect
unreachable code. Each chunk of dead code is assigned aconfidence valuebetween 60% and 100%, where a value of 100% signals that it is certain that the
code won't be executed. Values below 100% arevery roughestimates (based on
the type of code chunk) for how likely it is that the code is unused.Code typeConfidence valuefunction/method/class argument, unreachable code100%import90%attribute, class, function, method, property, variable60%You can use the--min-confidenceflag to set the minimum confidence
for code to be reported as unused. Use--min-confidence 100to only
report code that is guaranteed to be unused within the analyzed files.Handling false positivesWhen Vulture incorrectly reports chunks of code as unused, you have
several options for suppressing the false positives. If fixing your false
positives could benefit other users as well, please file an issue report.WhitelistsThe recommended option is to add used code that is reported as unused to a
Python module and add it to the list of scanned paths. To obtain such a
whitelist automatically, pass--make-whitelistto Vulture:$ vulture mydir --make-whitelist > whitelist.py
$ vulture mydir whitelist.pyNote that the resultingwhitelist.pyfile will contain valid Python
syntax, but for Python to be able torunit, you will usually have to
make some modifications.We collect whitelists for common Python modules and packages invulture/whitelists/(pull requests are welcome).Ignoring filesIf you want to ignore a whole file or directory, use the--excludeparameter
(e.g.,--exclude "*settings.py,*/docs/*.py,*/test_*.py,*/.venv/*.py"). The
exclude patterns are matched against absolute paths.Flake8 noqa commentsFor compatibility withflake8, Vulture
supports theF401 and
F841error
codes for ignoring unused imports (# noqa: F401) and unused local
variables (# noqa: F841). However, we recommend using whitelists instead
ofnoqacomments, sincenoqacomments add visual noise to the code and
make it harder to read.Ignoring namesYou can use--ignore-names foo*,ba[rz]to let Vulture ignore all names
starting withfooand the namesbarandbaz. Additionally, the--ignore-decoratorsoption can be used to ignore the names of functions
decorated with the given decorator (but not their arguments or function body).
This is helpful for example in Flask
projects, where you can use--ignore-decorators "@app.route"to ignore all
function names with the@app.routedecorator. Note that Vulture simplifies
decorators it cannot parse:@foo.bar(x, y)becomes "@foo.bar" and@foo.bar(x, y).bazbecomes "@" internally.We recommend using whitelists instead of--ignore-namesor--ignore-decoratorswhenever possible, since whitelists are
automatically checked for syntactic correctness when passed to Vulture
and often you can even pass them to your Python interpreter and let it
check that all whitelisted code actually still exists in your project.Marking unused variablesThere are situations where you can't just remove unused variables, e.g.,
in function signatures. The recommended solution is to use thedelkeyword as described in thePyLint manualand onStackOverflow:deffoo(x,y):delyreturnx+3Vulture will also ignore all variables that start with an underscore, so
you can use_x, y = get_pos()to mark unused tuple assignments or
function arguments, e.g.,def foo(x, _y).Minimum confidenceRaise the minimumconfidence valuewith the--min-confidenceflag.Unreachable codeIf Vulture complains about code likeif False:, you can use a Boolean
flagdebug = Falseand writeif debug:instead. This makes the code
more readable and silences Vulture.Forward references for type annotationsSee#216. For
example, instead ofdef foo(arg: "Sequence"): ..., we recommend usingfrom__future__importannotationsdeffoo(arg:Sequence):...ConfigurationYou can also store command line arguments inpyproject.tomlunder thetool.vulturesection. Simply remove leading dashes and replace all
remaining dashes with underscores.Options given on the command line have precedence over options inpyproject.toml.Example Config:[tool.vulture]exclude=["*file*.py","dir/"]ignore_decorators=["@app.route","@require_*"]ignore_names=["visit_*","do_*"]make_whitelist=truemin_confidence=80paths=["myscript.py","mydir","whitelist.py"]sort_by_size=trueverbose=trueVersion control integrationYou can use apre-commithook to run
Vulture before each commit. For this, install pre-commit and add the
following to the.pre-commit-config.yamlfile in your repository:repos:-repo:https://github.com/jendrikseipp/vulturerev:'v2.3'# or any later Vulture versionhooks:-id:vultureThen runpre-commit install. Finally, create apyproject.tomlfile
in your repository and specify all files that Vulture should check under[tool.vulture] --> paths(see above).How does it work?Vulture uses theastmodule to build abstract syntax trees for all
given files. While traversing all syntax trees it records the names of
defined and used objects. Afterwards, it reports the objects which have
been defined, but not used. This analysis ignores scopes and only takes
object names into account.Vulture also detects unreachable code by looking for code afterreturn,break,continueandraisestatements, and by searching
for unsatisfiableif- andwhile-conditions.Sort by sizeWhen using the--sort-by-sizeoption, Vulture sorts unused code by its
number of lines. This helps developers prioritize where to look for dead
code first.ExamplesConsider the following Python script (dead_code.py):importosclassGreeter:defgreet(self):print("Hi")defhello_world():message="Hello, world!"greeter=Greeter()func_name="greet"greet_func=getattr(greeter,func_name)greet_func()if__name__=="__main__":hello_world()Calling :$ vulture dead_code.pyresults in the following output:dead_code.py:1: unused import 'os' (90% confidence)
dead_code.py:4: unused function 'greet' (60% confidence)
dead_code.py:8: unused variable 'message' (60% confidence)Vulture correctly reportsosandmessageas unused but it fails to
detect thatgreetis actually used. The recommended method to deal
with false positives like this is to create a whitelist Python file.Preparing whitelistsIn a whitelist we simulate the usage of variables, attributes, etc. For
the program above, a whitelist could look as follows:# whitelist_dead_code.pyfromdead_codeimportGreeterGreeter.greetAlternatively, you can pass--make-whitelistto Vulture and obtain an
automatically generated whitelist.Passing both the original program and the whitelist to Vulture$ vulture dead_code.py whitelist_dead_code.pymakes Vulture ignore thegreetmethod:dead_code.py:1: unused import 'os' (90% confidence)
dead_code.py:8: unused variable 'message' (60% confidence)Exit codesExit codeDescription0No dead code found1Invalid input (file missing, syntax error, wrong encoding)2Invalid command line arguments3Dead code foundSimilar programspyflakesfinds unused imports
and unused local variables (in addition to many other programmatic
errors).coveragefinds unused code
more reliably than Vulture, but requires all branches of the code to
actually be run.uncalledfinds dead code by
using the abstract syntax tree (like Vulture), regular expressions,
or both.deadfinds dead code by using the
abstract syntax tree (like Vulture).ParticipatePlease visithttps://github.com/jendrikseipp/vultureto report any
issues or to make pull requests.Contributing guide:CONTRIBUTING.mdRelease notes:CHANGELOG.mdRoadmap:TODO.md2.11 (2024-01-06)Switch to tomllib/tomli to support heterogeneous arrays (Sebastian Csar, #340).Bump flake8, flake8-comprehensions and flake8-bugbear (Sebastian Csar, #341).Provide whitelist parity forMagicMockandMock(maxrake, #342).2.10 (2023-10-06)Drop support for Python 3.7 (Jendrik Seipp, #323).Add support for Python 3.12 (Jendrik Seipp, #332).Useend_linenoAST attribute to obtain more accurate line counts (Jendrik Seipp).2.9.1 (2023-08-21)Use exit code 0 for--helpand--versionagain (Jendrik Seipp, #321).2.9 (2023-08-20)Use exit code 3 when dead code is found (whosayn, #319).Treat non-supported decorator names as "@" instead of crashing (Llandy3d and Jendrik Seipp, #284).Drop support for Python 3.6 (Jendrik Seipp).2.8 (2023-08-10)AddUnicodeEncodeErrorexception handling tocore.py(milanbalazs, #299).Add whitelist forEnumattributes_name_and_value_(Eugene Toder, #305).Run tests and add PyPI trove for Python 3.11 (Jendrik Seipp).2.7 (2023-01-08)Ignoresetup_module(),teardown_module(), etc. in pytesttest_*.pyfiles (Jendrik Seipp).Add whitelist forsocketserver.TCPServer.allow_reuse_address(Ben Elliston).Clarify that--excludepatterns are matched against absolute paths (Jendrik Seipp, #260).Fix example in README file (Jendrik Seipp, #272).2.6 (2022-09-19)Add basicmatchstatement support (kreathon, #276, #291).2.5 (2022-07-03)Mark imports in__all__as used (kreathon, #172, #282).Add whitelist forpint.UnitRegistry.default_formatter(Ben Elliston, #258).2.4 (2022-05-19)Print absolute filepaths as relative again (as in version 2.1 and before)
if they are below the current directory (The-Compiler, #246).Run tests and add PyPI trove for Python 3.10 (chayim, #266).Allow using thedelkeyword to mark unused variables (sshishov, #279).2.3 (2021-01-16)Addpre-commithook (Clément Robert, #244).2.2 (2021-01-15)Only parse format strings when being used withlocals()(jingw, #225).Don't override paths in pyproject.toml with empty CLI paths (bcbnz, #228).Run continuous integration tests for Python 3.9 (ju-sh, #232).Use pathlib internally (ju-sh, #226).2.1 (2020-08-19)Treatgetattr/hasattr(obj, "constant_string", ...)as a reference toobj.constant_string(jingw, #219).Fix false positives when assigning tox.some_namebut reading viasome_name, at the cost of potential false negatives (jingw, #221).Allow reading options frompyproject.toml(Michel Albert, #164, #215).2.0 (2020-08-11)Parse# type: ...comments if on Python 3.8+ (jingw, #220).Bump minimum Python version to 3.6 (Jendrik Seipp, #218). The last
Vulture release that supports Python 2.7 and Python 3.5 is version 1.6.Consider all files undertestortestsdirectories test files
(Jendrik Seipp).Ignorelogging.Logger.propagateattribute (Jendrik Seipp).1.6 (2020-07-28)Differentiate between functions and methods (Jendrik Seipp, #112, #209).Move from Travis to GitHub actions (RJ722, #211).1.5 (2020-05-24)Support flake8 "noqa" error codes F401 (unused import) and F841 (unused
local variable) (RJ722, #195).Detect unreachable code in conditional expressions
(Agathiyan Bragadeesh, #178).1.4 (2020-03-30)Ignore unused import statements in__init__.py(RJ722, #192).Report first decorator's line number for unused decorated objects on
Python 3.8+ (RJ722, #200).Check code with black and pyupgrade.1.3 (2020-02-03)Detect redundant 'if' conditions without 'else' blocks.Add whitelist forstring.Formatter(Joseph Bylund, #183).1.2 (2019-11-22)Fix tests for Python 3.8 (#166).Use newConstantAST node under Python 3.8+ (#175).Add test for f-strings (#177).Add whitelist forloggingmodule.1.1 (2019-09-23)Addsys.excepthooktosyswhitelist.Add whitelist forctypesmodule.Check that type annotations are parsed and type comments are ignored
(thanks @kx-chen).Support checking files with BOM under Python 2.7 (#170).1.0 (2018-10-23)Add--ignore-decoratorsflag (thanks @RJ722).Add whitelist forthreadingmodule (thanks @andrewhalle).0.29 (2018-07-31)Add--ignore-namesflag for ignoring names matching the given glob
patterns (thanks @RJ722).0.28 (2018-07-05)Add--make-whitelistflag for reporting output in whitelist format
(thanks @RJ722).Ignore case of--excludearguments on Windows.Add*-test.pyto recognized test file patterns.AddfailureException,longMessageandmaxDifftounittestwhitelist.Refer to actual objects rather than their mocks in default
whitelists (thanks @RJ722).Don't import any Vulture modules in setup.py (thanks @RJ722).0.27 (2018-06-05)Reportwhile (True): ... else: ...as unreachable (thanks @RJ722).Useargparseinstead ofoptparse.Whitelist Mock.return_value and Mock.side_effect in unittest.mock
module.Drop support for Python 2.6 and 3.3.Improve documentation and test coverage (thanks @RJ722).0.26 (2017-08-28)Detectasyncfunction definitions (thanks @RJ722).AddItem.get_report()method (thanks @RJ722).Move method for finding Python modules out of Vulture class.0.25 (2017-08-15)Detect unsatisfiable statements containingand,orandnot.Use filenames and line numbers as tie-breakers when sorting by size.Store first and last line numbers in Item objects.Pass relevant options directly toscavenge()andreport().0.24 (2017-08-14)Detect unsatisfiablewhile-conditions (thanks @RJ722).Detect unsatisfiableif- andelse-conditions (thanks @RJ722).Handle null bytes in source code.0.23 (2017-08-10)Add--min-confidenceflag (thanks @RJ722).0.22 (2017-08-04)Detect unreachable code afterreturn,break,continueandraise(thanks @RJ722).Parse all variable and attribute names in new format strings.Extend ast whitelist.0.21 (2017-07-26)If an unused item is defined multiple times, report it multiple
times.Make size estimates for function calls more accurate.Create wheel files for Vulture (thanks @RJ722).0.20 (2017-07-26)Report unused tuple assignments as dead code.Report attribute names that have the same names as variables as dead
code.Let Item class inherit fromobject(thanks @RJ722).Handle names imported as aliases like all other used variable names.Rename Vulture.used_vars to Vulture.used_names.Use function for determining which imports to ignore.Only try to import each whitelist file once.Store used names and used attributes in sets instead of lists.Fix estimating the size of code containing ellipses (...).Refactor and simplify code.0.19 (2017-07-20)Don't ignore__foovariable names.Use separate methods for determining whether to ignore classes and
functions.Only try to find a whitelist for each defined import once (thanks
@roivanov).Fix finding the last child for many types of AST nodes.0.18 (2017-07-17)Make--sort-by-sizefaster and more
accurate (thanks @RJ722).0.17 (2017-07-17)Addget_unused_code()method.Return with exit code 1 when syntax errors are found or files can't
be read.0.16 (2017-07-12)Differentiate between unused classes and functions (thanks @RJ722).Add --sort-by-size option (thanks @jackric and @RJ722).Count imports as used if they are accessed as module attributes.0.15 (2017-07-04)Automatically include whitelists based on imported modules (thanks
@RJ722).Add --version parameter (thanks @RJ722).Add appveyor tests for testing on Windows (thanks @RJ722).0.14 (2017-04-06)Add stub whitelist file for Python standard library (thanks @RJ722)Ignore class names starting with "Test" in "test_" files (thanks
@thisch).Ignore "test_" functions only in "test_" files.0.13 (2017-03-06)Ignore star-imported names since we cannot detect whether they are
used.Move repository to GitHub.0.12 (2017-01-05)Detect unused imports.Use tokenize.open() on Python >= 3.2 for reading input files,
assume UTF-8 encoding on older Python versions.0.11 (2016-11-27)Use the system's default encoding when reading files.Report syntax errors instead of aborting.0.10 (2016-07-14)Detect unused function and method arguments (issue #15).Detect unused *args and **kwargs parameters.Change license from GPL to MIT.0.9 (2016-06-29)Don't flag attributes as unused if they are used as global variables
in another module (thanks Florian Bruhin).Don't consider "True" and "False" variable names.Abort with error message when invoked on .pyc files.0.8.1 (2015-09-28)Fix code for Python 3.0.8 (2015-09-28)Do not flag names imported with "import as" as dead code (thanks Tom
Terrace).0.7 (2015-09-26)Exit with exitcode 1 if path on commandline can't be found.Test vulture with vulture using a whitelist module for false
positives.Add tests that run vulture as a script.Add "python setup.py test" command for running tests.Add support for tox.Raise test coverage to 100%.Remove ez_setup.py.0.6 (2014-09-06)Ignore function names starting with "test_".Parse variable names in new format strings (e.g. "This is
{x}".format(x="nice")).Only parse alphanumeric variable names in format strings and ignore
types.Abort with exit code 1 on syntax errors.Support installation under Windows by using setuptools (thanks
Reuben Fletcher-Costin).0.5 (2014-05-09)If dead code is found, exit with 1.0.4.1 (2013-09-17)Only warn if a path given on the command line cannot be found.0.4 (2013-06-23)Ignore unused variables starting with an underscore.Show warning for syntax errors instead of aborting directly.Print warning if a file cannot be found.0.3 (2012-03-19)Add support for python3Report unused attributesFind tuple assignments in comprehensionsScan files given on the command line even if they don't end with .py0.2 (2012-03-18)Only format nodes in verbose mode (gives 4x speedup).0.1 (2012-03-17)First release.