Function collectRefsFromExpression

packages/db/src/query/builder/index.ts:1087–1102

* Recursively collects all PropRef nodes from an expression tree.

(expr: BasicExpression)

 * Recursively collects all PropRef nodes from an expression tree.
 */
function collectRefsFromExpression(expr: BasicExpression): Array<PropRef> {
  const refs: Array<PropRef> = []
  switch (expr.type) {
    case `ref`:
      refs.push(expr)
      break
    case `func`:
      for (const arg of (expr as any).args ?? []) {
        refs.push(...collectRefsFromExpression(arg))
      }
      break
    default:
      break
  }
  return refs
}

/**
 * Checks whether a WHERE clause references any parent alias.