CriticalFile-scopeDart Plug & play

Avoid Duplicating String Literals

Store repeated string literals in constants or variables to improve maintainability and reduce redundancy.

Why this matters

Duplicated string literals make refactoring harder and increase the risk of inconsistencies in the codebase.

Bad vs. good

Side-by-side examples engineers can pattern-match during review.

Avoid

class A {
  void run() {
    prepare('string literal');    // Noncompliant - "string literal" is duplicated 3 times
    execute('string literal');
    release('string literal');
  }
}

Prefer

class A {
  static const _const = 'string literal';

  void run() {
    prepare(_const);    // Compliant
    execute(_const);
    release(_const);
  }
}

More snippets

Bad

class A {
  void run() {
    prepare('string literal');    // Noncompliant - "string literal" is duplicated 3 times
    execute('string literal');
    release('string literal');
  }
}

Good

class A {
  static const _const = 'string literal';

  void run() {
    prepare(_const);    // Compliant
    execute(_const);
    release(_const);
  }
}

Related rules

From the same buckets as this rule.

Critical
Avoid Redundant `None` Comparisons
Identify cases where `x is None` or `x is not None` is used redundantly when `x` is always or never `None`. This may indicate a deeper logic issue.
duplication-complexityreadability-refactor+1
High
Avoid Functions That Always Return the Same Value
Identify functions that return the same value regardless of input. This may indicate poor design or a logic error.
duplication-complexityreadability-refactor+1
High
Avoid Unnecessary `toList()` with Spread Operator
Remove unnecessary calls to `.toList()` when using the spread operator (`...`) as it is already designed to work with iterable collections.
duplication-complexityperformance-efficiency+1

Why this matters

Bad vs. good

More snippets

Related rules

Avoid Redundant `None` Comparisons

Avoid Functions That Always Return the Same Value

Avoid Unnecessary `toList()` with Spread Operator

Why this matters

Bad vs. good

More snippets

Related rules

Avoid Redundant `None` Comparisons

Avoid Functions That Always Return the Same Value

Avoid Unnecessary `toList()` with Spread Operator