While searching through a Python project, I found a few lines commented with
import sys sys.path.append(r'C:dev') import some_module # noqa
noqa mean in Python? Is it specific to Python only?
# noqa to a line indicates that the linter (a program that automatically checks code quality) should not check this line. Any warnings that code may have generated will be ignored.
That line may have something that “looks bad” to the linter, but the developer understands and intends it to be there for some reason.
For more information, see the Flake8 documentation for Selecting and Ignoring Violations.
noqa = NO-QA (NO Quality Assurance)
It’s generally referred in Python Programming to ignore the PEP8 warnings.
In simple words, lines having #noqa at the end will be ignored by the linter programs and they won’t raise any warnings.
You know what? Even Guido van Rossum (the creator of Python) asked this question before 😀
It used to be “nopep8” but when Flake8 and Pep8 wanted a common
qualifier @florentx suggested “NoQA” as in “No Quality Assurance”
(iirc) and it stuck.
# flake8: noqa: files that contain this line are skipped
- lines that contain a
# noqacomment at the end: will not issue warnings
# noqa: <error>, e.g.,
# noqa: E234at the end: ignore specific errors on a line
- multiple error codes can be given, separated by comma
- the colon before the list of codes is required
Came here after finding a # noqa directive in a library that I was working with. Having never heard of it, I naturally arrived here after searching on Google. The answers provided here are adequate but I wanted to provide some further elaboration for those that may be curious (I certainly was)
# noqahas evolved from the # nopep8 syntax used in previous
releases of flake8
# noqais supported by IDEs, like PyCharm, for use with their
built-in code inspection tools.
# noqacan be used as a pre-commit directive, such that prior to new
commits an inspection process must complete
# noqacan be used to ignore all warnings or given specific warnings
to ignore. Example: # noqa: F401 – this will ignore an unused
imported module warning.
As an example, consider the following code:
import os print("Hello, world!)
This code imports the os module but doesn’t use it. If one wanted to use the # noqa tool to suppress a Pep8 warning, it could be written as such:
import os # noqa print("Hello, world!)
This will ignore all warnings. However, if one were only to want to ignore a specific warning (PEP8 F401 imported but not used), it could be done as such:
import os # noqa: F401 print("Hello, world!)
I’ve published an article with some noqa examples and more elaboration on the above points.