Cyclomatic complexity is too high in function list_serial_port_strings. (8) Open
def list_serial_port_strings():
"""Lists serial port names.
:raises EnvironmentError:
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Cyclomatic Complexity
Cyclomatic Complexity corresponds to the number of decisions a block of code contains plus 1. This number (also called McCabe number) is equal to the number of linearly independent paths through the code. This number can be used as a guide when testing conditional logic in blocks.
Radon analyzes the AST tree of a Python program to compute Cyclomatic Complexity. Statements have the following effects on Cyclomatic Complexity:
| Construct | Effect on CC | Reasoning |
|---|---|---|
| if | +1 | An if statement is a single decision. |
| elif | +1 | The elif statement adds another decision. |
| else | +0 | The else statement does not cause a new decision. The decision is at the if. |
| for | +1 | There is a decision at the start of the loop. |
| while | +1 | There is a decision at the while statement. |
| except | +1 | Each except branch adds a new conditional path of execution. |
| finally | +0 | The finally block is unconditionally executed. |
| with | +1 | The with statement roughly corresponds to a try/except block (see PEP 343 for details). |
| assert | +1 | The assert statement internally roughly equals a conditional statement. |
| Comprehension | +1 | A list/set/dict comprehension of generator expression is equivalent to a for loop. |
| Boolean Operator | +1 | Every boolean operator (and, or) adds a decision point. |
Function list_serial_port_strings has a Cognitive Complexity of 8 (exceeds 5 allowed). Consider refactoring. Open
def list_serial_port_strings():
"""Lists serial port names.
:raises EnvironmentError:
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Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Do not use bare 'except' Open
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When catching exceptions, mention specific exceptions when possible.
Okay: except Exception:
Okay: except BaseException:
E722: except:Expected 2 blank lines after class or function definition, found 1 Open
__all__ = ["list_serial_port_strings", "list_serial_ports", "SerialPort"]- Read upRead up
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Separate top-level function and class definitions with two blank lines.
Method definitions inside a class are separated by a single blank
line.
Extra blank lines may be used (sparingly) to separate groups of
related functions. Blank lines may be omitted between a bunch of
related one-liners (e.g. a set of dummy implementations).
Use blank lines in functions, sparingly, to indicate logical
sections.
Okay: def a():\n pass\n\n\ndef b():\n pass
Okay: def a():\n pass\n\n\nasync def b():\n pass
Okay: def a():\n pass\n\n\n# Foo\n# Bar\n\ndef b():\n pass
Okay: default = 1\nfoo = 1
Okay: classify = 1\nfoo = 1
E301: class Foo:\n b = 0\n def bar():\n pass
E302: def a():\n pass\n\ndef b(n):\n pass
E302: def a():\n pass\n\nasync def b(n):\n pass
E303: def a():\n pass\n\n\n\ndef b(n):\n pass
E303: def a():\n\n\n\n pass
E304: @decorator\n\ndef a():\n pass
E305: def a():\n pass\na()
E306: def a():\n def b():\n pass\n def c():\n pass