swift-custom-dump/Sources/CustomDump/Internal/String.swift

import Foundation

extension String {
  func indenting(by count: Int) -> String {
    self.indenting(with: String(repeating: " ", count: count))
  }

  func indenting(with prefix: String) -> String {
    guard !prefix.isEmpty else { return self }
    return "\(prefix)\(self.replacingOccurrences(of: "\n", with: "\n\(prefix)"))"
  }

  func hashCount(isMultiline: Bool) -> Int {
    let (quote, offset) = isMultiline ? ("\"\"\"", 2) : ("\"", 0)
    var substring = self[...]
    var hashCount = 0
    let pattern = "(\(quote)[#]*)"
    while let range = substring.range(of: pattern, options: .regularExpression) {
      let count = substring.distance(from: range.lowerBound, to: range.upperBound) - offset
      hashCount = max(count, hashCount)
      substring = substring[range.upperBound...]
    }
    return hashCount
  }
}