explicit null handling

Prefer explicit null and undefined handling over optional or nullable types. When possible, provide default values or objects instead of making parameters optional. When null/undefined checks are necessary, handle both values explicitly and use descriptive patterns.

copy reviewer prompt

Prompt

Reviewer Prompt
Deploy Agent

Prefer explicit null and undefined handling over optional or nullable types. When possible, provide default values or objects instead of making parameters optional. When null/undefined checks are necessary, handle both values explicitly and use descriptive patterns.

Instead of relying on optional parameters that create chains of conditional access:

// Avoid
interface MigrateSetupInput {
  schemaFilter?: MigrateTypes.SchemaFilter
}
// Later: schemaFilter?.['prop'] access

// Prefer
const defaultSchemaFilter = {
  externalTables: [],
  exclude: [],
} satisfies MigrateTypes.SchemaFilter

When checking for null/undefined values, be explicit about both:

// Handle both null and undefined
if (obj.currentTimeframe == null) {
  return {}
}

// Or check explicitly
if (response.body === null) {
  return reject(new Error('response.body is null'))
}

This approach reduces conditional access chains, makes code more predictable, prevents null reference errors, and improves type safety by making the presence or absence of values explicit rather than implicit.

Source discussions