Pylint features =============== Pylint global options and switches ---------------------------------- Pylint provides global options and switches. General options ~~~~~~~~~~~~~~~ :rcfile: Specify a configuration file. :init-hook: Python code to execute, usually for sys.path manipulation such as pygtk.require(). :errors-only: In error mode, checkers without error messages are disabled and for others, only the ERROR messages are displayed, and no reports are done by default :py3k: In Python 3 porting mode, all checkers will be disabled and only messages emitted by the porting checker will be displayed :ignore: Add files or directories to the blacklist. They should be base names, not paths. Default: ``CVS`` :ignore-patterns: Add files or directories matching the regex patterns to the blacklist. The regex matches against base names, not paths. :persistent: Pickle collected data for later comparisons. Default: ``yes`` :load-plugins: List of plugins (as comma separated values of python modules names) to load, usually to register additional checkers. :comment: :jobs: Use multiple processes to speed up Pylint. Default: ``1`` :unsafe-load-any-extension: Allow loading of arbitrary C extensions. Extensions are imported into the active Python interpreter and may run arbitrary code. :extension-pkg-whitelist: A comma-separated list of package or module names from where C extensions may be loaded. Extensions are loading into the active Python interpreter and may run arbitrary code :optimize-ast: Allow optimization of some AST trees. This will activate a peephole AST optimizer, which will apply various small optimizations. For instance, it can be used to obtain the result of joining multiple strings with the addition operator. Joining a lot of strings can lead to a maximum recursion error in Pylint and this flag can prevent that. It has one side effect, the resulting AST will be different than the one from reality. This option is deprecated and it will be removed in Pylint 2.0. :long-help: more verbose help. Commands options ~~~~~~~~~~~~~~~~ :help-msg: Display a help message for the given message id and exit. The value may be a comma separated list of message ids. :list-msgs: Generate pylint's messages. :list-conf-levels: Generate pylint's messages. :full-documentation: Generate pylint's full documentation. :generate-rcfile: Generate a sample configuration file according to the current configuration. You can put other options before this one to get them in the generated configuration. :generate-man: Generate pylint's man page. Messages control options ~~~~~~~~~~~~~~~~~~~~~~~~ :confidence: Only show warnings with the listed confidence levels. Leave empty to show all. Valid levels: HIGH, INFERENCE, INFERENCE_FAILURE, UNDEFINED :enable: Enable the message, report, category or checker with the given id(s). You can either give multiple identifier separated by comma (,) or put this option multiple time (only on the command line, not in the configuration file where it should appear only once). See also the "--disable" option for examples. :disable: Disable the message, report, category or checker with the given id(s). You can either give multiple identifiers separated by comma (,) or put this option multiple times (only on the command line, not in the configuration file where it should appear only once).You can also use "--disable=all" to disable everything first and then reenable specific checks. For example, if you want to run only the similarities checker, you can use "--disable=all --enable=similarities". If you want to run only the classes checker, but have no Warning level messages displayed, use"--disable=all --enable=classes --disable=W" Default: ``parameter-unpacking,setslice-method,range-builtin-not-iterating,raw_input-builtin,old-octal-literal,execfile-builtin,metaclass-assignment,file-builtin,dict-iter-method,old-raise-syntax,nonzero-method,no-absolute-import,old-division,long-builtin,indexing-exception,map-builtin-not-iterating,intern-builtin,oct-method,zip-builtin-not-iterating,raising-string,filter-builtin-not-iterating,unichr-builtin,hex-method,suppressed-message,reload-builtin,apply-builtin,getslice-method,old-ne-operator,useless-suppression,print-statement,round-builtin,next-method-called,unicode-builtin,delslice-method,input-builtin,dict-view-method,cmp-builtin,long-suffix,coerce-method,coerce-builtin,unpacking-in-except,using-cmp-argument,xrange-builtin,cmp-method,import-star-module-level,standarderror-builtin,basestring-builtin,reduce-builtin,backtick,buffer-builtin`` Reports options ~~~~~~~~~~~~~~~ :output-format: Set the output format. Available formats are text, parseable, colorized, msvs (visual studio) and html. You can also give a reporter class, eg mypackage.mymodule.MyReporterClass. Default: ``text`` :files-output: Put messages in a separate file for each module / package specified on the command line instead of printing them on stdout. Reports (if any) will be written in a file name "pylint_global.[txt|html]". This option is deprecated and it will be removed in Pylint 2.0. :reports: Tells whether to display a full report or only the messages Default: ``yes`` :evaluation: Python expression which should return a note less than 10 (10 is the highest note). You have access to the variables errors warning, statement which respectively contain the number of errors / warnings messages and the total number of statements analyzed. This is used by the global evaluation report (RP0004). Default: ``10.0 - ((float(5 * error + warning + refactor + convention) / statement) * 10)`` :msg-template: Template used to display messages. This is a python new-style format string used to format the message information. See doc for all details Pylint checkers' options and switches ------------------------------------- Pylint checkers can provide three set of features: * options that control their execution, * messages that they can raise, * reports that they can generate. Below is a list of all checkers and their features. Python3 checker ~~~~~~~~~~~~~~~ Verbatim name of the checker is ``python3``. Messages ~~~~~~~~ :unpacking-in-except (E1603): *Implicit unpacking of exceptions is not supported in Python 3* Python3 will not allow implicit unpacking of exceptions in except clauses. See http://www.python.org/dev/peps/pep-3110/ This message can't be emitted when using Python >= 3.0. :import-star-module-level (E1609): *Import * only allowed at module level* Used when the import star syntax is used somewhere else than the module level. This message can't be emitted when using Python >= 3.0. :parameter-unpacking (E1602): *Parameter unpacking specified* Used when parameter unpacking is specified for a function(Python 3 doesn't allow it) This message can't be emitted when using Python >= 3.0. :long-suffix (E1606): *Use of long suffix* Used when "l" or "L" is used to mark a long integer. This will not work in Python 3, since `int` and `long` types have merged. This message can't be emitted when using Python >= 3.0. :old-octal-literal (E1608): *Use of old octal literal* Usen when encountering the old octal syntax, removed in Python 3. To use the new syntax, prepend 0o on the number. This message can't be emitted when using Python >= 3.0. :old-ne-operator (E1607): *Use of the <> operator* Used when the deprecated "<>" operator is used instead of "!=". This is removed in Python 3. This message can't be emitted when using Python >= 3.0. :backtick (E1605): *Use of the `` operator* Used when the deprecated "``" (backtick) operator is used instead of the str() function. This message can't be emitted when using Python >= 3.0. :old-raise-syntax (E1604): *Use raise ErrorClass(args) instead of raise ErrorClass, args.* Used when the alternate raise syntax 'raise foo, bar' is used instead of 'raise foo(bar)'. This message can't be emitted when using Python >= 3.0. :print-statement (E1601): *print statement used* Used when a print statement is used (`print` is a function in Python 3) This message can't be emitted when using Python >= 3.0. :metaclass-assignment (W1623): *Assigning to a class's __metaclass__ attribute* Used when a metaclass is specified by assigning to __metaclass__ (Python 3 specifies the metaclass as a class statement argument) This message can't be emitted when using Python >= 3.0. :next-method-called (W1622): *Called a next() method on an object* Used when an object's next() method is called (Python 3 uses the next() built- in function) This message can't be emitted when using Python >= 3.0. :dict-iter-method (W1620): *Calling a dict.iter*() method* Used for calls to dict.iterkeys(), itervalues() or iteritems() (Python 3 lacks these methods) This message can't be emitted when using Python >= 3.0. :dict-view-method (W1621): *Calling a dict.view*() method* Used for calls to dict.viewkeys(), viewvalues() or viewitems() (Python 3 lacks these methods) This message can't be emitted when using Python >= 3.0. :indexing-exception (W1624): *Indexing exceptions will not work on Python 3* Indexing exceptions will not work on Python 3. Use `exception.args[index]` instead. This message can't be emitted when using Python >= 3.0. :raising-string (W1625): *Raising a string exception* Used when a string exception is raised. This will not work on Python 3. This message can't be emitted when using Python >= 3.0. :standarderror-builtin (W1611): *StandardError built-in referenced* Used when the StandardError built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :using-cmp-argument (W1640): *Using the cmp argument for list.sort / sorted* Using the cmp argument for list.sort or the sorted builtin should be avoided, since it was removed in Python 3. Using either `key` or `functools.cmp_to_key` should be preferred. This message can't be emitted when using Python >= 3.0. :cmp-method (W1630): *__cmp__ method defined* Used when a __cmp__ method is defined (method is not used by Python 3) This message can't be emitted when using Python >= 3.0. :coerce-method (W1614): *__coerce__ method defined* Used when a __coerce__ method is defined (method is not used by Python 3) This message can't be emitted when using Python >= 3.0. :delslice-method (W1615): *__delslice__ method defined* Used when a __delslice__ method is defined (method is not used by Python 3) This message can't be emitted when using Python >= 3.0. :getslice-method (W1616): *__getslice__ method defined* Used when a __getslice__ method is defined (method is not used by Python 3) This message can't be emitted when using Python >= 3.0. :hex-method (W1628): *__hex__ method defined* Used when a __hex__ method is defined (method is not used by Python 3) This message can't be emitted when using Python >= 3.0. :nonzero-method (W1629): *__nonzero__ method defined* Used when a __nonzero__ method is defined (method is not used by Python 3) This message can't be emitted when using Python >= 3.0. :oct-method (W1627): *__oct__ method defined* Used when a __oct__ method is defined (method is not used by Python 3) This message can't be emitted when using Python >= 3.0. :setslice-method (W1617): *__setslice__ method defined* Used when a __setslice__ method is defined (method is not used by Python 3) This message can't be emitted when using Python >= 3.0. :apply-builtin (W1601): *apply built-in referenced* Used when the apply built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :basestring-builtin (W1602): *basestring built-in referenced* Used when the basestring built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :buffer-builtin (W1603): *buffer built-in referenced* Used when the buffer built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :cmp-builtin (W1604): *cmp built-in referenced* Used when the cmp built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :coerce-builtin (W1605): *coerce built-in referenced* Used when the coerce built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :old-division (W1619): *division w/o __future__ statement* Used for non-floor division w/o a float literal or ``from __future__ import division`` (Python 3 returns a float for int division unconditionally) This message can't be emitted when using Python >= 3.0. :execfile-builtin (W1606): *execfile built-in referenced* Used when the execfile built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :file-builtin (W1607): *file built-in referenced* Used when the file built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :filter-builtin-not-iterating (W1639): *filter built-in referenced when not iterating* Used when the filter built-in is referenced in a non-iterating context (returns an iterator in Python 3) This message can't be emitted when using Python >= 3.0. :no-absolute-import (W1618): *import missing `from __future__ import absolute_import`* Used when an import is not accompanied by ``from __future__ import absolute_import`` (default behaviour in Python 3) This message can't be emitted when using Python >= 3.0. :input-builtin (W1632): *input built-in referenced* Used when the input built-in is referenced (backwards-incompatible semantics in Python 3) This message can't be emitted when using Python >= 3.0. :intern-builtin (W1634): *intern built-in referenced* Used when the intern built-in is referenced (Moved to sys.intern in Python 3) This message can't be emitted when using Python >= 3.0. :long-builtin (W1608): *long built-in referenced* Used when the long built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :map-builtin-not-iterating (W1636): *map built-in referenced when not iterating* Used when the map built-in is referenced in a non-iterating context (returns an iterator in Python 3) This message can't be emitted when using Python >= 3.0. :range-builtin-not-iterating (W1638): *range built-in referenced when not iterating* Used when the range built-in is referenced in a non-iterating context (returns an iterator in Python 3) This message can't be emitted when using Python >= 3.0. :raw_input-builtin (W1609): *raw_input built-in referenced* Used when the raw_input built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :reduce-builtin (W1610): *reduce built-in referenced* Used when the reduce built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :reload-builtin (W1626): *reload built-in referenced* Used when the reload built-in function is referenced (missing from Python 3). You can use instead imp.reload or importlib.reload. This message can't be emitted when using Python >= 3.0. :round-builtin (W1633): *round built-in referenced* Used when the round built-in is referenced (backwards-incompatible semantics in Python 3) This message can't be emitted when using Python >= 3.0. :unichr-builtin (W1635): *unichr built-in referenced* Used when the unichr built-in is referenced (Use chr in Python 3) This message can't be emitted when using Python >= 3.0. :unicode-builtin (W1612): *unicode built-in referenced* Used when the unicode built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :xrange-builtin (W1613): *xrange built-in referenced* Used when the xrange built-in function is referenced (missing from Python 3) This message can't be emitted when using Python >= 3.0. :zip-builtin-not-iterating (W1637): *zip built-in referenced when not iterating* Used when the zip built-in is referenced in a non-iterating context (returns an iterator in Python 3) This message can't be emitted when using Python >= 3.0. Spelling checker ~~~~~~~~~~~~~~~~ Verbatim name of the checker is ``spelling``. Options ^^^^^^^ :spelling-dict: Spelling dictionary name. Available dictionaries: none. To make it working install python-enchant package. :spelling-ignore-words: List of comma separated words that should not be checked. :spelling-private-dict-file: A path to a file that contains private dictionary; one word per line. :spelling-store-unknown-words: Tells whether to store unknown words to indicated private dictionary in --spelling-private-dict-file option instead of raising a message. Messages ~~~~~~~~ :invalid-characters-in-docstring (C0403): *Invalid characters %r in a docstring* Used when a word in docstring cannot be checked by enchant. :wrong-spelling-in-comment (C0401): *Wrong spelling of a word '%s' in a comment:* Used when a word in comment is not spelled correctly. :wrong-spelling-in-docstring (C0402): *Wrong spelling of a word '%s' in a docstring:* Used when a word in docstring is not spelled correctly. Basic checker ~~~~~~~~~~~~~ Verbatim name of the checker is ``basic``. Options ^^^^^^^ :required-attributes: Required attributes for module. This option is obsolete. :good-names: Good variable names which should always be accepted, separated by a comma Default: ``i,j,k,ex,Run,_`` :bad-names: Bad variable names which should always be refused, separated by a comma Default: ``foo,bar,baz,toto,tutu,tata`` :name-group: Colon-delimited sets of names that determine each other's naming style when the name regexes allow several styles. :include-naming-hint: Include a hint for the correct naming format with invalid-name :property-classes: List of decorators that produce properties, such as abc.abstractproperty. Add to this list to register other decorators that produce valid properties. Default: ``abc.abstractproperty`` :function-rgx: Regular expression matching correct function names Default: ``[a-z_][a-z0-9_]{2,30}$`` :function-name-hint: Naming hint for function names Default: ``[a-z_][a-z0-9_]{2,30}$`` :inlinevar-rgx: Regular expression matching correct inline iteration names Default: ``[A-Za-z_][A-Za-z0-9_]*$`` :inlinevar-name-hint: Naming hint for inline iteration names Default: ``[A-Za-z_][A-Za-z0-9_]*$`` :variable-rgx: Regular expression matching correct variable names Default: ``[a-z_][a-z0-9_]{2,30}$`` :variable-name-hint: Naming hint for variable names Default: ``[a-z_][a-z0-9_]{2,30}$`` :class-attribute-rgx: Regular expression matching correct class attribute names Default: ``([A-Za-z_][A-Za-z0-9_]{2,30}|(__.*__))$`` :class-attribute-name-hint: Naming hint for class attribute names Default: ``([A-Za-z_][A-Za-z0-9_]{2,30}|(__.*__))$`` :argument-rgx: Regular expression matching correct argument names Default: ``[a-z_][a-z0-9_]{2,30}$`` :argument-name-hint: Naming hint for argument names Default: ``[a-z_][a-z0-9_]{2,30}$`` :const-rgx: Regular expression matching correct constant names Default: ``(([A-Z_][A-Z0-9_]*)|(__.*__))$`` :const-name-hint: Naming hint for constant names Default: ``(([A-Z_][A-Z0-9_]*)|(__.*__))$`` :attr-rgx: Regular expression matching correct attribute names Default: ``[a-z_][a-z0-9_]{2,30}$`` :attr-name-hint: Naming hint for attribute names Default: ``[a-z_][a-z0-9_]{2,30}$`` :module-rgx: Regular expression matching correct module names Default: ``(([a-z_][a-z0-9_]*)|([A-Z][a-zA-Z0-9]+))$`` :module-name-hint: Naming hint for module names Default: ``(([a-z_][a-z0-9_]*)|([A-Z][a-zA-Z0-9]+))$`` :class-rgx: Regular expression matching correct class names Default: ``[A-Z_][a-zA-Z0-9]+$`` :class-name-hint: Naming hint for class names Default: ``[A-Z_][a-zA-Z0-9]+$`` :method-rgx: Regular expression matching correct method names Default: ``[a-z_][a-z0-9_]{2,30}$`` :method-name-hint: Naming hint for method names Default: ``[a-z_][a-z0-9_]{2,30}$`` :no-docstring-rgx: Regular expression which should only match function or class names that do not require a docstring. Default: ``^_`` :docstring-min-length: Minimum line length for functions/classes that require docstrings, shorter ones are exempt. Default: ``-1`` Messages ~~~~~~~~ :not-in-loop (E0103): *%r not properly in loop* Used when break or continue keywords are used outside a loop. :function-redefined (E0102): *%s already defined line %s* Used when a function / class / method is redefined. :continue-in-finally (E0116): *'continue' not supported inside 'finally' clause* Emitted when the `continue` keyword is found inside a finally clause, which is a SyntaxError. :abstract-class-instantiated (E0110): *Abstract class %r with abstract methods instantiated* Used when an abstract class with `abc.ABCMeta` as metaclass has abstract methods and is instantiated. :star-needs-assignment-target (E0114): *Can use starred expression only in assignment target* Emitted when a star expression is not used in an assignment target. This message can't be emitted when using Python < 3.0. :duplicate-argument-name (E0108): *Duplicate argument name %s in function definition* Duplicate argument names in function definitions are syntax errors. :return-in-init (E0101): *Explicit return in __init__* Used when the special class method __init__ has an explicit return value. :too-many-star-expressions (E0112): *More than one starred expression in assignment* Emitted when there are more than one starred expressions (`*x`) in an assignment. This is a SyntaxError. This message can't be emitted when using Python < 3.0. :nonlocal-and-global (E0115): *Name %r is nonlocal and global* Emitted when a name is both nonlocal and global. This message can't be emitted when using Python < 3.0. :return-outside-function (E0104): *Return outside function* Used when a "return" statement is found outside a function or method. :return-arg-in-generator (E0106): *Return with argument inside generator* Used when a "return" statement with an argument is found outside in a generator function or method (e.g. with some "yield" statements). This message can't be emitted when using Python >= 3.3. :invalid-star-assignment-target (E0113): *Starred assignment target must be in a list or tuple* Emitted when a star expression is used as a starred assignment target. This message can't be emitted when using Python < 3.0. :bad-reversed-sequence (E0111): *The first reversed() argument is not a sequence* Used when the first argument to reversed() builtin isn't a sequence (does not implement __reversed__, nor __getitem__ and __len__ :nonexistent-operator (E0107): *Use of the non-existent %s operator* Used when you attempt to use the C-style pre-increment orpre-decrement operator -- and ++, which doesn't exist in Python. :yield-outside-function (E0105): *Yield outside function* Used when a "yield" statement is found outside a function or method. :init-is-generator (E0100): *__init__ method is a generator* Used when the special class method __init__ is turned into a generator by a yield in its body. :nonlocal-without-binding (E0117): *nonlocal name %s found without binding* Emitted when a nonlocal variable does not have an attached name somewhere in the parent scopes This message can't be emitted when using Python < 3.0. :lost-exception (W0150): *%s statement in finally block may swallow exception* Used when a break or a return statement is found inside the finally clause of a try...finally block: the exceptions raised in the try clause will be silently swallowed instead of being re-raised. :assert-on-tuple (W0199): *Assert called on a 2-uple. Did you mean 'assert x,y'?* A call of assert on a tuple will always evaluate to true if the tuple is not empty, and will always evaluate to false if it is. :dangerous-default-value (W0102): *Dangerous default value %s as argument* Used when a mutable value as list or dictionary is detected in a default value for an argument. :duplicate-key (W0109): *Duplicate key %r in dictionary* Used when a dictionary expression binds the same key multiple times. :useless-else-on-loop (W0120): *Else clause on loop without a break statement* Loops should only have an else clause if they can exit early with a break statement, otherwise the statements under else should be on the same scope as the loop itself. :expression-not-assigned (W0106): *Expression "%s" is assigned to nothing* Used when an expression that is not a function call is assigned to nothing. Probably something else was intended. :confusing-with-statement (W0124): *Following "as" with another context manager looks like a tuple.* Emitted when a `with` statement component returns multiple values and uses name binding with `as` only for a part of those values, as in with ctx() as a, b. This can be misleading, since it's not clear if the context manager returns a tuple or if the node without a name binding is another context manager. :unnecessary-lambda (W0108): *Lambda may not be necessary* Used when the body of a lambda expression is a function call on the same argument list as the lambda itself; such lambda expressions are in all but a few cases replaceable with the function being called in the body of the lambda. :pointless-statement (W0104): *Statement seems to have no effect* Used when a statement doesn't have (or at least seems to) any effect. :pointless-string-statement (W0105): *String statement has no effect* Used when a string is used as a statement (which of course has no effect). This is a particular case of W0104 with its own message so you can easily disable it if you're using those strings as documentation, instead of comments. :unnecessary-pass (W0107): *Unnecessary pass statement* Used when a "pass" statement that can be avoided is encountered. :unreachable (W0101): *Unreachable code* Used when there is some code behind a "return" or "raise" statement, which will never be accessed. :eval-used (W0123): *Use of eval* Used when you use the "eval" function, to discourage its usage. Consider using `ast.literal_eval` for safely evaluating strings containing Python expressions from untrusted sources. :exec-used (W0122): *Use of exec* Used when you use the "exec" statement (function for Python 3), to discourage its usage. That doesn't mean you can not use it ! :using-constant-test (W0125): *Using a conditional statement with a constant value* Emitted when a conditional statement (If or ternary if) uses a constant value for its test. This might not be what the user intended to do. :deprecated-lambda (W0110): *map/filter on lambda could be replaced by comprehension* Used when a lambda is the first argument to "map" or "filter". It could be clearer as a list comprehension or generator expression. This message can't be emitted when using Python >= 3.0. :blacklisted-name (C0102): *Black listed name "%s"* Used when the name is listed in the black list (unauthorized names). :misplaced-comparison-constant (C0122): *Comparison should be %s* Used when the constant is placed on the left sideof a comparison. It is usually clearer in intent to place it in the right hand side of the comparison. :singleton-comparison (C0121): *Comparison to %s should be %s* Used when an expression is compared to singleton values like True, False or None. :unneeded-not (C0113): *Consider changing "%s" to "%s"* Used when a boolean expression contains an unneeded negation. :consider-iterating-dictionary (C0201): *Consider iterating the dictionary directly instead of calling .keys()* Emitted when the keys of a dictionary are iterated through the .keys() method. It is enough to just iterate through the dictionary itself, as in "for key in dictionary". :consider-using-enumerate (C0200): *Consider using enumerate instead of iterating with range and len* Emitted when code that iterates with range and len is encountered. Such code can be simplified by using the enumerate builtin. :empty-docstring (C0112): *Empty %s docstring* Used when a module, function, class or method has an empty docstring (it would be too easy ;). :invalid-name (C0103): *Invalid %s name "%s"%s* Used when the name doesn't match the regular expression associated to its type (constant, variable, class...). :missing-docstring (C0111): *Missing %s docstring* Used when a module, function, class or method has no docstring.Some special methods like __init__ doesn't necessary require a docstring. :unidiomatic-typecheck (C0123): *Using type() instead of isinstance() for a typecheck.* The idiomatic way to perform an explicit typecheck in Python is to use isinstance(x, Y) rather than type(x) == Y, type(x) is Y. Though there are unusual situations where these give different results. Reports ~~~~~~~ :RP0101: Statistics by type Async checker ~~~~~~~~~~~~~ Verbatim name of the checker is ``async``. Messages ~~~~~~~~ :not-async-context-manager (E1701): *Async context manager '%s' doesn't implement __aenter__ and __aexit__.* Used when an async context manager is used with an object that does not implement the async context management protocol. This message can't be emitted when using Python < 3.5. :yield-inside-async-function (E1700): *Yield inside async function* Used when an `yield` or `yield from` statement is found inside an async function. This message can't be emitted when using Python < 3.5. Typecheck checker ~~~~~~~~~~~~~~~~~ Verbatim name of the checker is ``typecheck``. Options ^^^^^^^ :ignore-mixin-members: Tells whether missing members accessed in mixin class should be ignored. A mixin class is detected if its name ends with "mixin" (case insensitive). Default: ``yes`` :ignored-modules: List of module names for which member attributes should not be checked (useful for modules/projects where namespaces are manipulated during runtime and thus existing member attributes cannot be deduced by static analysis. It supports qualified module names, as well as Unix pattern matching. :ignored-classes: List of class names for which member attributes should not be checked (useful for classes with dynamically set attributes). This supports the use of qualified names. Default: ``optparse.Values,thread._local,_thread._local`` :generated-members: List of members which are set dynamically and missed by pylint inference system, and so shouldn't trigger E1101 when accessed. Python regular expressions are accepted. :contextmanager-decorators: List of decorators that produce context managers, such as contextlib.contextmanager. Add to this list to register other decorators that produce valid context managers. Default: ``contextlib.contextmanager`` Messages ~~~~~~~~ :invalid-unary-operand-type (E1130): Emitted when an unary operand is used on an object which does not support this type of operation :unsupported-binary-operation (E1131): Emitted when a binary arithmetic operation between two operands is not supported. :no-member (E1101): *%s %r has no %r member* Used when a variable is accessed for an unexistent member. :not-callable (E1102): *%s is not callable* Used when an object being called has been inferred to a non callable object :redundant-keyword-arg (E1124): *Argument %r passed by position and keyword in %s call* Used when a function call would result in assigning multiple values to a function parameter, one value from a positional argument and one from a keyword argument. :assignment-from-no-return (E1111): *Assigning to function call which doesn't return* Used when an assignment is done on a function call but the inferred function doesn't return anything. :assignment-from-none (E1128): *Assigning to function call which only returns None* Used when an assignment is done on a function call but the inferred function returns nothing but None. :not-context-manager (E1129): *Context manager '%s' doesn't implement __enter__ and __exit__.* Used when an instance in a with statement doesn't implement the context manager protocol(__enter__/__exit__). :repeated-keyword (E1132): *Got multiple values for keyword argument %r in function call* Emitted when a function call got multiple values for a keyword. :missing-kwoa (E1125): *Missing mandatory keyword argument %r in %s call* Used when a function call does not pass a mandatory keyword-only argument. This message can't be emitted when using Python < 3.0. :no-value-for-parameter (E1120): *No value for argument %s in %s call* Used when a function call passes too few arguments. :invalid-sequence-index (E1126): *Sequence index is not an int, slice, or instance with __index__* Used when a sequence type is indexed with an invalid type. Valid types are ints, slices, and objects with an __index__ method. :invalid-slice-index (E1127): *Slice index is not an int, None, or instance with __index__* Used when a slice index is not an integer, None, or an object with an __index__ method. :too-many-function-args (E1121): *Too many positional arguments for %s call* Used when a function call passes too many positional arguments. :unexpected-keyword-arg (E1123): *Unexpected keyword argument %r in %s call* Used when a function call passes a keyword argument that doesn't correspond to one of the function's parameter names. :unsupported-membership-test (E1135): *Value '%s' doesn't support membership test* Emitted when an instance in membership test expression doesn'timplement membership protocol (__contains__/__iter__/__getitem__) :unsubscriptable-object (E1136): *Value '%s' is unsubscriptable* Emitted when a subscripted value doesn't support subscription(i.e. doesn't define __getitem__ method) Exceptions checker ~~~~~~~~~~~~~~~~~~ Verbatim name of the checker is ``exceptions``. Options ^^^^^^^ :overgeneral-exceptions: Exceptions that will emit a warning when being caught. Defaults to "Exception" Default: ``Exception`` Messages ~~~~~~~~ :bad-except-order (E0701): *Bad except clauses order (%s)* Used when except clauses are not in the correct order (from the more specific to the more generic). If you don't fix the order, some exceptions may not be catched by the most specific handler. :catching-non-exception (E0712): *Catching an exception which doesn't inherit from BaseException: %s* Used when a class which doesn't inherit from BaseException is used as an exception in an except clause. :bad-exception-context (E0703): *Exception context set to something which is not an exception, nor None* Used when using the syntax "raise ... from ...", where the exception context is not an exception, nor None. This message can't be emitted when using Python < 3.0. :notimplemented-raised (E0711): *NotImplemented raised - should raise NotImplementedError* Used when NotImplemented is raised instead of NotImplementedError :raising-bad-type (E0702): *Raising %s while only classes or instances are allowed* Used when something which is neither a class, an instance or a string is raised (i.e. a `TypeError` will be raised). :raising-non-exception (E0710): *Raising a new style class which doesn't inherit from BaseException* Used when a new style class which doesn't inherit from BaseException is raised. :misplaced-bare-raise (E0704): *The raise statement is not inside an except clause* Used when a bare raise is not used inside an except clause. This generates an error, since there are no active exceptions to be reraised. An exception to this rule is represented by a bare raise inside a finally clause, which might work, as long as an exception is raised inside the try block, but it is nevertheless a code smell that must not be relied upon. :duplicate-except (W0705): *Catching previously caught exception type %s* Used when an except catches a type that was already caught by a previous handler. :broad-except (W0703): *Catching too general exception %s* Used when an except catches a too general exception, possibly burying unrelated errors. :nonstandard-exception (W0710): *Exception doesn't inherit from standard "Exception" class* Used when a custom exception class is raised but doesn't inherit from the builtin "Exception" class. This message can't be emitted when using Python >= 3.0. :binary-op-exception (W0711): *Exception to catch is the result of a binary "%s" operation* Used when the exception to catch is of the form "except A or B:". If intending to catch multiple, rewrite as "except (A, B):" :bare-except (W0702): *No exception type(s) specified* Used when an except clause doesn't specify exceptions type to catch. Miscellaneous checker ~~~~~~~~~~~~~~~~~~~~~ Verbatim name of the checker is ``miscellaneous``. Options ^^^^^^^ :notes: List of note tags to take in consideration, separated by a comma. Default: ``FIXME,XXX,TODO`` Messages ~~~~~~~~ :fixme (W0511): Used when a warning note as FIXME or XXX is detected. :invalid-encoded-data (W0512): *Cannot decode using encoding "%s", unexpected byte at position %d* Used when a source line cannot be decoded using the specified source file encoding. This message can't be emitted when using Python >= 3.0. Stdlib checker ~~~~~~~~~~~~~~ Verbatim name of the checker is ``stdlib``. Messages ~~~~~~~~ :bad-open-mode (W1501): *"%s" is not a valid mode for open.* Python supports: r, w, a[, x] modes with b, +, and U (only with r) options. See http://docs.python.org/2/library/functions.html#open :redundant-unittest-assert (W1503): *Redundant use of %s with constant value %r* The first argument of assertTrue and assertFalse is a condition. If a constant is passed as parameter, that condition will be always true. In this case a warning should be emitted. :boolean-datetime (W1502): *Using datetime.time in a boolean context.* Using datetime.time in a boolean context can hide subtle bugs when the time they represent matches midnight UTC. This behaviour was fixed in Python 3.5. See http://bugs.python.org/issue13936 for reference. This message can't be emitted when using Python >= 3.5. :deprecated-method (W1505): *Using deprecated method %s()* The method is marked as deprecated and will be removed in a future version of Python. Consider looking for an alternative in the documentation. Imports checker ~~~~~~~~~~~~~~~ Verbatim name of the checker is ``imports``. Options ^^^^^^^ :deprecated-modules: Deprecated modules which should not be used, separated by a comma Default: ``optparse`` :import-graph: Create a graph of every (i.e. internal and external) dependencies in the given file (report RP0402 must not be disabled) :ext-import-graph: Create a graph of external dependencies in the given file (report RP0402 must not be disabled) :int-import-graph: Create a graph of internal dependencies in the given file (report RP0402 must not be disabled) :known-standard-library: Force import order to recognize a module as part of the standard compatibility libraries. :known-third-party: Force import order to recognize a module as part of a third party library. Default: ``enchant`` :analyse-fallback-blocks: Analyse import fallback blocks. This can be used to support both Python 2 and 3 compatible code, which means that the block might have code that exists only in one or another interpreter, leading to false positives when analysed. Messages ~~~~~~~~ :import-error (E0401): *Unable to import %s* Used when pylint has been unable to import a module. :import-self (W0406): *Module import itself* Used when a module is importing itself. :reimported (W0404): *Reimport %r (imported line %s)* Used when a module is reimported multiple times. :relative-import (W0403): *Relative import %r, should be %r* Used when an import relative to the package directory is detected. This message can't be emitted when using Python >= 3.0. :deprecated-module (W0402): *Uses of a deprecated module %r* Used a module marked as deprecated is imported. :wildcard-import (W0401): *Wildcard import %s* Used when `from module import *` is detected. :misplaced-future (W0410): *__future__ import is not the first non docstring statement* Python 2.5 and greater require __future__ import to be the first non docstring statement in the module. :cyclic-import (R0401): *Cyclic import (%s)* Used when a cyclic import between two or more modules is detected. :wrong-import-order (C0411): *%s comes before %s* Used when PEP8 import order is not respected (standard imports first, then third-party libraries, then local imports) :wrong-import-position (C0413): *Import "%s" should be placed at the top of the module* Used when code and imports are mixed :ungrouped-imports (C0412): *Imports from package %s are not grouped* Used when imports are not grouped by packages :multiple-imports (C0410): *Multiple imports on one line (%s)* Used when import statement importing multiple modules is detected. Reports ~~~~~~~ :RP0401: External dependencies :RP0402: Modules dependencies graph Design checker ~~~~~~~~~~~~~~ Verbatim name of the checker is ``design``. Options ^^^^^^^ :max-args: Maximum number of arguments for function / method Default: ``5`` :ignored-argument-names: Argument names that match this expression will be ignored. Default to name with leading underscore Default: ``_.*`` :max-locals: Maximum number of locals for function / method body Default: ``15`` :max-returns: Maximum number of return / yield for function / method body Default: ``6`` :max-branches: Maximum number of branch for function / method body Default: ``12`` :max-statements: Maximum number of statements in function / method body Default: ``50`` :max-parents: Maximum number of parents for a class (see R0901). Default: ``7`` :max-attributes: Maximum number of attributes for a class (see R0902). Default: ``7`` :min-public-methods: Minimum number of public methods for a class (see R0903). Default: ``2`` :max-public-methods: Maximum number of public methods for a class (see R0904). Default: ``20`` :max-bool-expr: Maximum number of boolean expressions in a if statement Default: ``5`` Messages ~~~~~~~~ :too-few-public-methods (R0903): *Too few public methods (%s/%s)* Used when class has too few public methods, so be sure it's really worth it. :too-many-ancestors (R0901): *Too many ancestors (%s/%s)* Used when class has too many parent classes, try to reduce this to get a simpler (and so easier to use) class. :too-many-arguments (R0913): *Too many arguments (%s/%s)* Used when a function or method takes too many arguments. :too-many-boolean-expressions (R0916): *Too many boolean expressions in if statement (%s/%s)* Used when a if statement contains too many boolean expressions :too-many-branches (R0912): *Too many branches (%s/%s)* Used when a function or method has too many branches, making it hard to follow. :too-many-instance-attributes (R0902): *Too many instance attributes (%s/%s)* Used when class has too many instance attributes, try to reduce this to get a simpler (and so easier to use) class. :too-many-locals (R0914): *Too many local variables (%s/%s)* Used when a function or method has too many local variables. :too-many-public-methods (R0904): *Too many public methods (%s/%s)* Used when class has too many public methods, try to reduce this to get a simpler (and so easier to use) class. :too-many-return-statements (R0911): *Too many return statements (%s/%s)* Used when a function or method has too many return statement, making it hard to follow. :too-many-statements (R0915): *Too many statements (%s/%s)* Used when a function or method has too many statements. You should then split it in smaller functions / methods. Variables checker ~~~~~~~~~~~~~~~~~ Verbatim name of the checker is ``variables``. Options ^^^^^^^ :init-import: Tells whether we should check for unused import in __init__ files. :dummy-variables-rgx: A regular expression matching the name of dummy variables (i.e. expectedly not used). Default: ``(_+[a-zA-Z0-9]*?$)|dummy`` :additional-builtins: List of additional names supposed to be defined in builtins. Remember that you should avoid to define new builtins when possible. :callbacks: List of strings which can identify a callback function by name. A callback name must start or end with one of those strings. Default: ``cb_,_cb`` :redefining-builtins-modules: List of qualified module names which can have objects that can redefine builtins. Default: ``six.moves,future.builtins`` Messages ~~~~~~~~ :unpacking-non-sequence (E0633): *Attempting to unpack a non-sequence%s* Used when something which is not a sequence is used in an unpack assignment :invalid-all-object (E0604): *Invalid object %r in __all__, must contain only strings* Used when an invalid (non-string) object occurs in __all__. :no-name-in-module (E0611): *No name %r in module %r* Used when a name cannot be found in a module. :unbalanced-tuple-unpacking (E0632): *Possible unbalanced tuple unpacking with sequence%s: left side has %d label(s), right side has %d value(s)* Used when there is an unbalanced tuple unpacking in assignment :undefined-variable (E0602): *Undefined variable %r* Used when an undefined variable is accessed. :undefined-all-variable (E0603): *Undefined variable name %r in __all__* Used when an undefined variable name is referenced in __all__. :used-before-assignment (E0601): *Using variable %r before assignment* Used when a local variable is accessed before it's assignment. :cell-var-from-loop (W0640): *Cell variable %s defined in loop* A variable used in a closure is defined in a loop. This will result in all closures using the same value for the closed-over variable. :global-variable-undefined (W0601): *Global variable %r undefined at the module level* Used when a variable is defined through the "global" statement but the variable is not defined in the module scope. :redefined-builtin (W0622): *Redefining built-in %r* Used when a variable or function override a built-in. :redefine-in-handler (W0623): *Redefining name %r from %s in exception handler* Used when an exception handler assigns the exception to an existing name :redefined-outer-name (W0621): *Redefining name %r from outer scope (line %s)* Used when a variable's name hide a name defined in the outer scope. :unused-import (W0611): *Unused %s* Used when an imported module or variable is not used. :unused-argument (W0613): *Unused argument %r* Used when a function or method argument is not used. :unused-wildcard-import (W0614): *Unused import %s from wildcard import* Used when an imported module or variable is not used from a `'from X import *'` style import. :unused-variable (W0612): *Unused variable %r* Used when a variable is defined but not used. :global-variable-not-assigned (W0602): *Using global for %r but no assignment is done* Used when a variable is defined through the "global" statement but no assignment to this variable is done. :undefined-loop-variable (W0631): *Using possibly undefined loop variable %r* Used when an loop variable (i.e. defined by a for loop or a list comprehension or a generator expression) is used outside the loop. :global-statement (W0603): *Using the global statement* Used when you use the "global" statement to update a global variable. Pylint just try to discourage this usage. That doesn't mean you can not use it ! :global-at-module-level (W0604): *Using the global statement at the module level* Used when you use the "global" statement at the module level since it has no effect String checker ~~~~~~~~~~~~~~ Verbatim name of the checker is ``string``. Messages ~~~~~~~~ :format-needs-mapping (E1303): *Expected mapping for format string, not %s* Used when a format string that uses named conversion specifiers is used with an argument that is not a mapping. :truncated-format-string (E1301): *Format string ends in middle of conversion specifier* Used when a format string terminates before the end of a conversion specifier. :missing-format-string-key (E1304): *Missing key %r in format string dictionary* Used when a format string that uses named conversion specifiers is used with a dictionary that doesn't contain all the keys required by the format string. :mixed-format-string (E1302): *Mixing named and unnamed conversion specifiers in format string* Used when a format string contains both named (e.g. '%(foo)d') and unnamed (e.g. '%d') conversion specifiers. This is also used when a named conversion specifier contains * for the minimum field width and/or precision. :too-few-format-args (E1306): *Not enough arguments for format string* Used when a format string that uses unnamed conversion specifiers is given too few arguments :bad-str-strip-call (E1310): *Suspicious argument in %s.%s call* The argument to a str.{l,r,}strip call contains a duplicate character, :too-many-format-args (E1305): *Too many arguments for format string* Used when a format string that uses unnamed conversion specifiers is given too many arguments. :bad-format-character (E1300): *Unsupported format character %r (%#02x) at index %d* Used when a unsupported format character is used in a format string. :format-combined-specification (W1305): *Format string contains both automatic field numbering and manual field specification* Usen when a PEP 3101 format string contains both automatic field numbering (e.g. '{}') and manual field specification (e.g. '{0}'). This message can't be emitted when using Python < 2.7. :bad-format-string-key (W1300): *Format string dictionary key should be a string, not %s* Used when a format string that uses named conversion specifiers is used with a dictionary whose keys are not all strings. :bad-format-string (W1302): *Invalid format string* Used when a PEP 3101 format string is invalid. This message can't be emitted when using Python < 2.7. :missing-format-attribute (W1306): *Missing format attribute %r in format specifier %r* Used when a PEP 3101 format string uses an attribute specifier ({0.length}), but the argument passed for formatting doesn't have that attribute. This message can't be emitted when using Python < 2.7. :missing-format-argument-key (W1303): *Missing keyword argument %r for format string* Used when a PEP 3101 format string that uses named fields doesn't receive one or more required keywords. This message can't be emitted when using Python < 2.7. :unused-format-string-argument (W1304): *Unused format argument %r* Used when a PEP 3101 format string that uses named fields is used with an argument that is not required by the format string. This message can't be emitted when using Python < 2.7. :unused-format-string-key (W1301): *Unused key %r in format string dictionary* Used when a format string that uses named conversion specifiers is used with a dictionary that contains keys not required by the format string. :invalid-format-index (W1307): *Using invalid lookup key %r in format specifier %r* Used when a PEP 3101 format string uses a lookup specifier ({a[1]}), but the argument passed for formatting doesn't contain or doesn't have that key as an attribute. This message can't be emitted when using Python < 2.7. Elif checker ~~~~~~~~~~~~ Verbatim name of the checker is ``elif``. Options ^^^^^^^ :max-nested-blocks: Maximum number of nested blocks for function / method body Default: ``5`` Messages ~~~~~~~~ :simplifiable-if-statement (R0102): *The if statement can be replaced with %s* Used when an if statement can be replaced with 'bool(test)'. :too-many-nested-blocks (R0101): *Too many nested blocks (%s/%s)* Used when a function or a method has too many nested blocks. This makes the code less understandable and maintainable. Multiple Types checker ~~~~~~~~~~~~~~~~~~~~~~ Verbatim name of the checker is ``multiple_types``. Messages ~~~~~~~~ :redefined-variable-type (R0204): *Redefinition of %s type from %s to %s* Used when the type of a variable changes inside a method or a function. String Constant checker ~~~~~~~~~~~~~~~~~~~~~~~ Verbatim name of the checker is ``string_constant``. Messages ~~~~~~~~ :anomalous-unicode-escape-in-string (W1402): *Anomalous Unicode escape in byte string: '%s'. String constant might be missing an r or u prefix.* Used when an escape like \u is encountered in a byte string where it has no effect. :anomalous-backslash-in-string (W1401): *Anomalous backslash in string: '%s'. String constant might be missing an r prefix.* Used when a backslash is in a literal string but not as an escape. Metrics checker ~~~~~~~~~~~~~~~ Verbatim name of the checker is ``metrics``. Reports ~~~~~~~ :RP0701: Raw metrics Logging checker ~~~~~~~~~~~~~~~ Verbatim name of the checker is ``logging``. Options ^^^^^^^ :logging-modules: Logging modules to check that the string format arguments are in logging function parameter format Default: ``logging`` Messages ~~~~~~~~ :logging-format-truncated (E1201): *Logging format string ends in middle of conversion specifier* Used when a logging statement format string terminates before the end of a conversion specifier. :logging-too-few-args (E1206): *Not enough arguments for logging format string* Used when a logging format string is given too many arguments :logging-too-many-args (E1205): *Too many arguments for logging format string* Used when a logging format string is given too few arguments. :logging-unsupported-format (E1200): *Unsupported logging format character %r (%#02x) at index %d* Used when an unsupported format character is used in a logging statement format string. :logging-not-lazy (W1201): *Specify string format arguments as logging function parameters* Used when a logging statement has a call form of "logging.(format_string % (format_args...))". Such calls should leave string interpolation to the logging method itself and be written "logging.(format_string, format_args...)" so that the program may avoid incurring the cost of the interpolation in those cases in which no message will be logged. For more, see http://www.python.org/dev/peps/pep-0282/. :logging-format-interpolation (W1202): *Use % formatting in logging functions and pass the % parameters as arguments* Used when a logging statement has a call form of "logging.(format_string.format(format_args...))". Such calls should use % formatting instead, but leave interpolation to the logging function by passing the parameters as arguments. Iterable Check checker ~~~~~~~~~~~~~~~~~~~~~~ Verbatim name of the checker is ``iterable_check``. Messages ~~~~~~~~ :not-an-iterable (E1133): *Non-iterable value %s is used in an iterating context* Used when a non-iterable value is used in place whereiterable is expected :not-a-mapping (E1134): *Non-mapping value %s is used in a mapping context* Used when a non-mapping value is used in place wheremapping is expected Similarities checker ~~~~~~~~~~~~~~~~~~~~ Verbatim name of the checker is ``similarities``. Options ^^^^^^^ :min-similarity-lines: Minimum lines number of a similarity. Default: ``4`` :ignore-comments: Ignore comments when computing similarities. Default: ``yes`` :ignore-docstrings: Ignore docstrings when computing similarities. Default: ``yes`` :ignore-imports: Ignore imports when computing similarities. Messages ~~~~~~~~ :duplicate-code (R0801): *Similar lines in %s files* Indicates that a set of similar lines has been detected among multiple file. This usually means that the code should be refactored to avoid this duplication. Reports ~~~~~~~ :RP0801: Duplication Format checker ~~~~~~~~~~~~~~ Verbatim name of the checker is ``format``. Options ^^^^^^^ :max-line-length: Maximum number of characters on a single line. Default: ``100`` :ignore-long-lines: Regexp for a line that is allowed to be longer than the limit. Default: ``^\s*(# )??$`` :single-line-if-stmt: Allow the body of an if to be on the same line as the test if there is no else. :no-space-check: List of optional constructs for which whitespace checking is disabled. `dict- separator` is used to allow tabulation in dicts, etc.: {1 : 1,\n222: 2}. `trailing-comma` allows a space between comma and closing bracket: (a, ). `empty-line` allows space-only lines. Default: ``trailing-comma,dict-separator`` :max-module-lines: Maximum number of lines in a module Default: ``1000`` :indent-string: String used as indentation unit. This is usually " " (4 spaces) or "\t" (1 tab). Default: ``' '`` :indent-after-paren: Number of spaces of indent required inside a hanging or continued line. Default: ``4`` :expected-line-ending-format: Expected format of line ending, e.g. empty (any line ending), LF or CRLF. Messages ~~~~~~~~ :bad-indentation (W0311): *Bad indentation. Found %s %s, expected %s* Used when an unexpected number of indentation's tabulations or spaces has been found. :mixed-indentation (W0312): *Found indentation with %ss instead of %ss* Used when there are some mixed tabs and spaces in a module. :unnecessary-semicolon (W0301): *Unnecessary semicolon* Used when a statement is ended by a semi-colon (";"), which isn't necessary (that's python, not C ;). :lowercase-l-suffix (W0332): *Use of "l" as long integer identifier* Used when a lower case "l" is used to mark a long integer. You should use a upper case "L" since the letter "l" looks too much like the digit "1" This message can't be emitted when using Python >= 3.0. :bad-whitespace (C0326): *%s space %s %s %s* Used when a wrong number of spaces is used around an operator, bracket or block opener. :missing-final-newline (C0304): *Final newline missing* Used when the last line in a file is missing a newline. :line-too-long (C0301): *Line too long (%s/%s)* Used when a line is longer than a given number of characters. :mixed-line-endings (C0327): *Mixed line endings LF and CRLF* Used when there are mixed (LF and CRLF) newline signs in a file. :multiple-statements (C0321): *More than one statement on a single line* Used when more than on statement are found on the same line. :too-many-lines (C0302): *Too many lines in module (%s/%s)* Used when a module has too much lines, reducing its readability. :trailing-newlines (C0305): *Trailing newlines* Used when there are trailing blank lines in a file. :trailing-whitespace (C0303): *Trailing whitespace* Used when there is whitespace between the end of a line and the newline. :unexpected-line-ending-format (C0328): *Unexpected line ending format. There is '%s' while it should be '%s'.* Used when there is different newline than expected. :superfluous-parens (C0325): *Unnecessary parens after %r keyword* Used when a single item in parentheses follows an if, for, or other keyword. :bad-continuation (C0330): *Wrong %s indentation%s%s.* TODO Newstyle checker ~~~~~~~~~~~~~~~~ Verbatim name of the checker is ``newstyle``. Messages ~~~~~~~~ :bad-super-call (E1003): *Bad first argument %r given to super()* Used when another argument than the current class is given as first argument of the super builtin. :missing-super-argument (E1004): *Missing argument to super()* Used when the super builtin didn't receive an argument. This message can't be emitted when using Python >= 3.0. :slots-on-old-class (E1001): *Use of __slots__ on an old style class* Used when an old style class uses the __slots__ attribute. This message can't be emitted when using Python >= 3.0. :super-on-old-class (E1002): *Use of super on an old style class* Used when an old style class uses the super builtin. This message can't be emitted when using Python >= 3.0. :property-on-old-class (W1001): *Use of "property" on an old style class* Used when Pylint detect the use of the builtin "property" on an old style class while this is relying on new style classes features. This message can't be emitted when using Python >= 3.0. :old-style-class (C1001): *Old-style class defined.* Used when a class is defined that does not inherit from anotherclass and does not inherit explicitly from "object". This message can't be emitted when using Python >= 3.0. Classes checker ~~~~~~~~~~~~~~~ Verbatim name of the checker is ``classes``. Options ^^^^^^^ :ignore-iface-methods: This is deprecated, because it is not used anymore. :defining-attr-methods: List of method names used to declare (i.e. assign) instance attributes. Default: ``__init__,__new__,setUp`` :valid-classmethod-first-arg: List of valid names for the first argument in a class method. Default: ``cls`` :valid-metaclass-classmethod-first-arg: List of valid names for the first argument in a metaclass class method. Default: ``mcs`` :exclude-protected: List of member names, which should be excluded from the protected access warning. Default: ``_asdict,_fields,_replace,_source,_make`` Messages ~~~~~~~~ :access-member-before-definition (E0203): *Access to member %r before its definition line %s* Used when an instance member is accessed before it's actually assigned. :method-hidden (E0202): *An attribute defined in %s line %s hides this method* Used when a class defines a method which is hidden by an instance attribute from an ancestor class or set by some client code. :assigning-non-slot (E0237): *Assigning to attribute %r not defined in class slots* Used when assigning to an attribute not defined in the class slots. :duplicate-bases (E0241): *Duplicate bases for class %r* Used when a class has duplicate bases. :inconsistent-mro (E0240): *Inconsistent method resolution order for class %r* Used when a class has an inconsistent method resolutin order. :inherit-non-class (E0239): *Inheriting %r, which is not a class.* Used when a class inherits from something which is not a class. :invalid-slots (E0238): *Invalid __slots__ object* Used when an invalid __slots__ is found in class. Only a string, an iterable or a sequence is permitted. :invalid-slots-object (E0236): *Invalid object %r in __slots__, must contain only non empty strings* Used when an invalid (non-string) object occurs in __slots__. :no-method-argument (E0211): *Method has no argument* Used when a method which should have the bound instance as first argument has no argument defined. :no-self-argument (E0213): *Method should have "self" as first argument* Used when a method has an attribute different the "self" as first argument. This is considered as an error since this is a so common convention that you shouldn't break it! :unexpected-special-method-signature (E0302): *The special method %r expects %s param(s), %d %s given* Emitted when a special method was defined with an invalid number of parameters. If it has too few or too many, it might not work at all. :non-iterator-returned (E0301): *__iter__ returns non-iterator* Used when an __iter__ method returns something which is not an iterable (i.e. has no `__next__` method) :invalid-length-returned (E0303): *__len__ does not return non-negative integer* Used when an __len__ method returns something which is not a non-negative integer :protected-access (W0212): *Access to a protected member %s of a client class* Used when a protected member (i.e. class member with a name beginning with an underscore) is access outside the class or a descendant of the class where it's defined. :arguments-differ (W0221): *Arguments number differs from %s %r method* Used when a method has a different number of arguments than in the implemented interface or in an overridden method. :attribute-defined-outside-init (W0201): *Attribute %r defined outside __init__* Used when an instance attribute is defined outside the __init__ method. :no-init (W0232): *Class has no __init__ method* Used when a class has no __init__ method, neither its parent classes. :abstract-method (W0223): *Method %r is abstract in class %r but is not overridden* Used when an abstract method (i.e. raise NotImplementedError) is not overridden in concrete class. :signature-differs (W0222): *Signature differs from %s %r method* Used when a method signature is different than in the implemented interface or in an overridden method. :bad-staticmethod-argument (W0211): *Static method with %r as first argument* Used when a static method has "self" or a value specified in valid- classmethod-first-arg option or valid-metaclass-classmethod-first-arg option as first argument. :non-parent-init-called (W0233): *__init__ method from a non direct base class %r is called* Used when an __init__ method is called on a class which is not in the direct ancestors for the analysed class. :super-init-not-called (W0231): *__init__ method from base class %r is not called* Used when an ancestor class method has an __init__ method which is not called by a derived class. :no-classmethod-decorator (R0202): *Consider using a decorator instead of calling classmethod* Used when a class method is defined without using the decorator syntax. :no-staticmethod-decorator (R0203): *Consider using a decorator instead of calling staticmethod* Used when a static method is defined without using the decorator syntax. :no-self-use (R0201): *Method could be a function* Used when a method doesn't use its bound instance, and so could be written as a function. :bad-classmethod-argument (C0202): *Class method %s should have %s as first argument* Used when a class method has a first argument named differently than the value specified in valid-classmethod-first-arg option (default to "cls"), recommended to easily differentiate them from regular instance methods. :bad-mcs-classmethod-argument (C0204): *Metaclass class method %s should have %s as first argument* Used when a metaclass class method has a first argument named differently than the value specified in valid-metaclass-classmethod-first-arg option (default to "mcs"), recommended to easily differentiate them from regular instance methods. :bad-mcs-method-argument (C0203): *Metaclass method %s should have %s as first argument* Used when a metaclass method has a first agument named differently than the value specified in valid-classmethod-first-arg option (default to "cls"), recommended to easily differentiate them from regular instance methods. :method-check-failed (F0202): *Unable to check methods signature (%s / %s)* Used when Pylint has been unable to check methods signature compatibility for an unexpected reason. Please report this kind if you don't make sense of it.