old_contents: #!/usr/bin/env python
  # touch.py - /bin/touch that writes the LLVM epoch -*- python -*-
  #
  # This source file is part of the Swift.org open source project
  #
  # Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors
  # Licensed under Apache License v2.0 with Runtime Library Exception
  #
  # See http://swift.org/LICENSE.txt for license information
  # See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
  #
  # ----------------------------------------------------------------------------
  #
  # Like /bin/touch, but takes a time using the LLVM epoch.
  #
  # ----------------------------------------------------------------------------
  
  import os
  import sys
  
  assert len(sys.argv) >= 2
  timeVal = int(sys.argv[1])
  
  # offset between Unix and LLVM epochs
  timeVal += 946684800
  
  # Update the output file mtime, or create it if necessary.
  # From http://stackoverflow.com/a/1160227.
  for outputFile in sys.argv[1:]:
      with open(outputFile, 'a'):
          os.utime(outputFile, (timeVal, timeVal))
  
new_contents: #!/usr/bin/env python
  # touch.py - /bin/touch that writes the LLVM epoch -*- python -*-
  #
  # This source file is part of the Swift.org open source project
  #
  # Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors
  # Licensed under Apache License v2.0 with Runtime Library Exception
  #
  # See http://swift.org/LICENSE.txt for license information
  # See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
  #
  # ----------------------------------------------------------------------------
  #
  # Like /bin/touch, but takes a time using the system_clock epoch.
  #
  # ----------------------------------------------------------------------------
  
  import os
  import sys
  
  assert len(sys.argv) >= 2
  timeVal = int(sys.argv[1])
  
  # Update the output file mtime, or create it if necessary.
  # From http://stackoverflow.com/a/1160227.
  for outputFile in sys.argv[1:]:
      with open(outputFile, 'a'):
          os.utime(outputFile, (timeVal, timeVal))
  
subject: Fix tests for file timestamps to drop the LLVM epoch offset.