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Sarj Code Standards

no-logical-or-fallback

Use nullish defaults or explicit falsy-value checks instead of logical OR fallbacks.

logicalOrFallback Rule source Tests Catalog JSON

Why

Logical OR falls back for empty strings, zero and false as well as missing values. This hides which values should actually receive a default.

Fix

Use ?? for null or undefined. If an empty string, zero or false needs special handling, test that condition explicitly and preserve the intended behavior.

Examples

Before — flagged Do not hide empty-string fallback behavior
src/title.ts
export function title(value: string) {
  return value.trim() || "Untitled";
}
After — preferred Preserve an intentional empty-string default
src/title.ts
export function title(value: string) {
  const trimmed = value.trim();
  return trimmed === "" ? "Untitled" : trimmed;
}

References