alchemyst/Skogestad-Python

Duplicated Code

Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:

Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.

When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).

Tuning

This issue has a mass of 37.

We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.

The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.

If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.

See codeclimate-duplication's documentation for more information about tuning the mass threshold in your .codeclimate.yml.

Refactorings

• Extract Method
• Extract Class
• Form Template Method
• Introduce Null Object
• Pull Up Method
• Pull Up Field
• Substitute Algorithm

Further Reading

• Don't Repeat Yourself on the C2 Wiki
• Duplicated Code on SourceMaking
• Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76

Limit all lines to a maximum of 79 characters.

There are still many devices around that are limited to 80 character
lines; plus, limiting windows to 80 characters makes it possible to
have several windows side-by-side.  The default wrapping on such
devices looks ugly.  Therefore, please limit all lines to a maximum
of 79 characters. For flowing long blocks of text (docstrings or
comments), limiting the length to 72 characters is recommended.

Reports error E501.

Each comma, semicolon or colon should be followed by whitespace.

Okay: [a, b]
Okay: (3,)
Okay: a[1:4]
Okay: a[:4]
Okay: a[1:]
Okay: a[1:4:2]
E231: ['a','b']
E231: foo(bar,baz)
E231: [{'a':'b'}]

Compound statements (on the same line) are generally discouraged.

While sometimes it's okay to put an if/for/while with a small body
on the same line, never do this for multi-clause statements.
Also avoid folding such long lines!

Always use a def statement instead of an assignment statement that
binds a lambda expression directly to a name.

Okay: if foo == 'blah':\n    do_blah_thing()
Okay: do_one()
Okay: do_two()
Okay: do_three()

E701: if foo == 'blah': do_blah_thing()
E701: for x in lst: total += x
E701: while t < 10: t = delay()
E701: if foo == 'blah': do_blah_thing()
E701: else: do_non_blah_thing()
E701: try: something()
E701: finally: cleanup()
E701: if foo == 'blah': one(); two(); three()
E702: do_one(); do_two(); do_three()
E703: do_four();  # useless semicolon
E704: def f(x): return 2*x
E731: f = lambda x: 2*x

Limit all lines to a maximum of 79 characters.

There are still many devices around that are limited to 80 character
lines; plus, limiting windows to 80 characters makes it possible to
have several windows side-by-side.  The default wrapping on such
devices looks ugly.  Therefore, please limit all lines to a maximum
of 79 characters. For flowing long blocks of text (docstrings or
comments), limiting the length to 72 characters is recommended.

Reports error E501.

Each comma, semicolon or colon should be followed by whitespace.

Okay: [a, b]
Okay: (3,)
Okay: a[1:4]
Okay: a[:4]
Okay: a[1:]
Okay: a[1:4:2]
E231: ['a','b']
E231: foo(bar,baz)
E231: [{'a':'b'}]

Use indent_size (PEP8 says 4) spaces per indentation level.

For really old code that you don't want to mess up, you can continue
to use 8-space tabs.

Okay: a = 1
Okay: if a == 0:\n    a = 1
E111:   a = 1
E114:   # a = 1

Okay: for item in items:\n    pass
E112: for item in items:\npass
E115: for item in items:\n# Hi\n    pass

Okay: a = 1\nb = 2
E113: a = 1\n    b = 2
E116: a = 1\n    # b = 2