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 55.

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

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 55.

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

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 55.

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

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 55.

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

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 50.

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

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 50.

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

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

• Cognitive Complexity docs
• Cognitive Complexity: A new way of measuring understandability

Force Element Nesting

Rule force-element-nesting will enforce the nesting of elements

Examples

When enabled, the following are disallowed:

div p {
  content: '';
}

.parent {
  &__child h1 {
    content: '';
  }
}

a[target="_blank"] span {
  content: '';
}

When enabled, the following are allowed:

div {
  p {
    content: '';
  }
}

.parent {
  &__child {
    h1 {
      content: '';
    }
  }
}

a[target="_blank"] {
  span {
    content: '';
  }
}

Space Around Operator

Rule space-around-operator will enforce whether or not a single space should be included before and after the following operators: +, -, /, *, %, <, > ==, !=, <= and >=.

Options

• include: true/false (defaults to true)

Examples

When include: true, the following are allowed. When include: false, the following are disallowed:

.foo {
  margin: 5px + 15px;
}

$foo: 1;
$bar: 3;

.foo {
  margin: $foo + $bar + 'px';
}

$foo: 1 + 1;
$bar: 2 - 1;

@if $foo == $bar {
  $baz: 1;
}

@if ($foo != $bar) {
  $baz: 1;
}

When include: false, the following are allowed. When include: true, the following are disallowed:

.foo {
  margin: 5px+15px;
}

$foo: 1;
$bar: 3;

.foo {
  margin: $foo+$bar+'px';
}

$foo: 1+1;
$bar: 2-1;

@if $foo==$bar {
  $baz: 1;
}

@if ($foo!=$bar) {
  $baz: 1;
}

When include: true or include: false multiple spaces around operators are disallowed:

.foo {
  margin: 5px   +       15px;
}

$foo: 1      +1;
$bar: 2-     1;

Brace Style

Rule brace-style will enforce the use of the chosen brace style.

Options

• style: '1tbs', 'stroustrup', 'allman' (defaults to 1tbs)
• allow-single-line: true/false (defaults to true)

Examples

style

When style: '1tbs' or style: 'stroustrup', the following are allowed. When style: 'allman' the following are disallowed:

.foo {
  content: 'foo';
}

.foo,
.bar {
  content: 'bar';
}

@function foo() {
  @return 'foo';
}

@mixin bar() {
  content: 'bar';
}

When style: 'allman', the following are allowed. When style: '1tbs' or style: 'stroustrup', the following are disallowed:

.foo
{
  content: 'foo';
}

.foo,
.bar
{
  content: 'bar';
}

@function foo()
{
  @return 'foo';
}

@mixin bar()
{
  content: 'bar';
}

Differences between 1tbs and stroustrup

When style: '1tbs', the following are allowed. When style: 'stroustrup' or style: 'allman', the following are disallowed:

@if ($foo) {
  $bar: 'bar';
} @else {
  $bar: false;
}

When style: 'stroustrup', the following are allowed. When style: '1tbs' or style: 'stroustrup', the following are disallowed:

@if ($foo) {
  $bar: 'bar';
}
@else {
  $bar: false;
}

allow-single-line

When allow-single-line: true, the following are allowed. When allow-single-line: false, the following are disallowed:

.foo { content: 'foo'; }
.foo, .bar { content: 'bar'; }

@if ($foo) { $bar: 'foo'; }

// Allowed with style: '1tbs', disallowed with style: 'stroustrup' or style: 'allman'
@if ($foo) { $bar: 'foo'; } @else { $bar: false; }

// Allowed with style: 'stroustrup' or style: 'allman', disallowed with style: '1tbs'
@if ($foo) { $bar: 'foo'; }
@else { $bar: false; }

Nesting Depth

Rule nesting-depth will enforce how deeply a selector can be nested.

Options

• max-depth: number (defaults to 2)

Examples

When enabled (assuming max-depth: 2) the deepest element (&:hover and &--modifier) are at at depth 2. Any nested selector deeper is disallowed:

.foo {
  .baz {
    &:hover {
      // Deepest Nest Allowed
    }
  }
}

.block {
  &__element {
    &--modifier {
      // Deepest Nest Allowed
    }
  }
}

Empty Line Between Blocks

Rule empty-line-between-blocks will enforce whether or not nested blocks should include a space between the last non-comment declaration or not.

Options

• include: true/false (defaults to true)
• allow-single-line-rulesets: true/false (defaults to true)

Examples

include

When include: true, the following are allowed. When include: false, the following are disallowed:

.foo {
  content: 'foo';

  .bar {
    content: 'bar';

    // Waldo
    &--baz {
      content: 'baz';
    }
  }
}

When include: false, the following are allowed. When include: true, the following are disallowed:

.foo {
  content: 'foo';
  .bar {
    content: 'bar';
    // Waldo
    &--baz {
      content: 'baz';
    }
  }
}

allow-single-line-rulesets

When allow-single-line-rulesets: true, the following are allowed. When allow-single-line-rulesets: false, the following are disallowed:

.foo { content: 'foo'; }
.bar { content: 'bar'; }
.baz { content: 'baz'; }

Space Around Operator

Rule space-around-operator will enforce whether or not a single space should be included before and after the following operators: +, -, /, *, %, <, > ==, !=, <= and >=.

Options

• include: true/false (defaults to true)

Examples

When include: true, the following are allowed. When include: false, the following are disallowed:

.foo {
  margin: 5px + 15px;
}

$foo: 1;
$bar: 3;

.foo {
  margin: $foo + $bar + 'px';
}

$foo: 1 + 1;
$bar: 2 - 1;

@if $foo == $bar {
  $baz: 1;
}

@if ($foo != $bar) {
  $baz: 1;
}

When include: false, the following are allowed. When include: true, the following are disallowed:

.foo {
  margin: 5px+15px;
}

$foo: 1;
$bar: 3;

.foo {
  margin: $foo+$bar+'px';
}

$foo: 1+1;
$bar: 2-1;

@if $foo==$bar {
  $baz: 1;
}

@if ($foo!=$bar) {
  $baz: 1;
}

When include: true or include: false multiple spaces around operators are disallowed:

.foo {
  margin: 5px   +       15px;
}

$foo: 1      +1;
$bar: 2-     1;

Nesting Depth

Rule nesting-depth will enforce how deeply a selector can be nested.

Options

• max-depth: number (defaults to 2)

Examples

When enabled (assuming max-depth: 2) the deepest element (&:hover and &--modifier) are at at depth 2. Any nested selector deeper is disallowed:

.foo {
  .baz {
    &:hover {
      // Deepest Nest Allowed
    }
  }
}

.block {
  &__element {
    &--modifier {
      // Deepest Nest Allowed
    }
  }
}

Force Element Nesting

Rule force-element-nesting will enforce the nesting of elements

Examples

When enabled, the following are disallowed:

div p {
  content: '';
}

.parent {
  &__child h1 {
    content: '';
  }
}

a[target="_blank"] span {
  content: '';
}

When enabled, the following are allowed:

div {
  p {
    content: '';
  }
}

.parent {
  &__child {
    h1 {
      content: '';
    }
  }
}

a[target="_blank"] {
  span {
    content: '';
  }
}

No Duplicate Properties

Rule no-duplicate-properties will enforce that duplicate properties are not allowed within the same block.

Options

• exclude: [array of property names to be excluded from this rule] (defaults to empty array [])

Examples

When enabled, the following are disallowed:

.foo {
  margin: 0 0 15px;
  margin: 0;
}

Exclude

When a property is added to the exclude array as shown below then you may place duplicate properties immediately after one another, this is to prevent accidental duplication of properties.

no-duplicate-properties:
  - 1
  -
    exclude:
      - display

When display is added to the exclude array the following would be allowed:

.display-block {
  display: flex;
  display: inline-block;
  float: right;
}

When display is added to the exclude array the following would still be disallowed as the duplicate properties are separated by another property:

.display-block {
  display: flex;
  float: right;
  display: inline-block;
}