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avoid-collapsible-if

added in: 1.1.0
style
🛠
Pro+

Warns when multiple nested if statements can be merged into one.

Nested if statements add extra levels of indentation and can reduce readability.

Example​

❌ Bad:

void main () {
  int value1 = 1;
  int value2 = 2;

  if (value1 == 1) {
    // LINT: Avoid collapsible 'if' statements. Try merging them into one 'if' statement.
    if (value2 == 2) {
      return;
    }
  }

  if (value1 == 1 && value2 == 3) {
    // LINT: Avoid collapsible 'if' statements. Try merging them into one 'if' statement.
    if (value2 == 2) {
      return;
    }
  }

  if (value1 == 1 || value2 == 3) {
    // LINT: Avoid collapsible 'if' statements. Try merging them into one 'if' statement.
    if (value2 == 2) {
      return;
    }
  }

  if (value1 == 1 || value2 == 3) {
    // LINT: Avoid collapsible 'if' statements. Try merging them into one 'if' statement.
    if (value2 == 2 || value1 == 4) {
      return;
    }
  }
}

✅ Good:

void main () {
  int value1 = 1;
  int value2 = 2;

  // Correct, one 'if' statement with compound condition
  if (value1 == 1 && value2 == 2) {
    return;
  }

  if (value1 == 1 && value2 == 3 && value2 == 2) {
    return;
  }

  if ((value1 == 1 || value2 == 3) && value2 == 2) {
    return;
  }

  if ((value1 == 1 || value2 == 3) && (value2 == 2 || value1 == 4)) {
    return;
  }

  if (value == 1 && value2 == 2) return;
}