Shell and Swift versions of a little script to compare Swift benchmark output files

benchmarkcompare.swift

/*
Shell version:

paste -d , oldoutput.txt output.txt | awk -F "," '{printf "%s %s %s %f\n", $2, $8, $16, $8 / $16}' | sort -k4 | egrep -v "(1\.0|0\.9[1-9])"
*/

import Foundation

// "paste -d , oldfile.txt newfile.txt"
let paths = CommandLine.arguments[1...2].map(URL.init(fileURLWithPath:))
let files = paths.map {
  try! String(contentsOf: $0.standardized, encoding: .utf8)
}
let lines = files.map { $0.split(separator: "\n") }
let merged = zip(lines[0], lines[1]).map { "\($0),\($1)" }

// awk -F "," '{printf "%s %s %s %f\n", $2, $8, $16, $8 / $16}'
// Almost, anyway… leaving the last field as a Double for now
let results = merged.map { (line) -> (text: String, ratio: Double) in
  let columns = line.split(separator: ",")
  return (
    "\(columns[1]) \(columns[7]) \(columns[15])",
    Double(columns[7])! / Double(columns[15])!
  )
}

//sort -k4
let sorted = results.sorted { $0.ratio < $1.ratio }

// Last bit of the 'awk' invocation since we're done with using them numerically
let formatted = sorted.map { "\($0.text) \($0.ratio)" }

//egrep -v "(1\.0|0\.9[1-9])"
let filtered = formatted.filter {
  $0.range(of: #"(1\.0|0\.9[1-9])"#, options: .regularExpression) == nil
}

print(filtered)