Batch File Rename Script

README.md

Batch File Rename

Use JavaScript for Automation to rename files in batch!

Motivation

While working on some client-side code at Oozou, I often have to rename a lot of image files. For example, Bourbon uses _2x.png for retina images, rather than @2x.png used by Retina.js.

I used to do this manually, until I am fed up and write this script.

Screenshot

rename.js

var app = Application.currentApplication()
app.includeStandardAdditions = true

var Finder = Application('Finder')
var selection = [].slice.call(Finder.selection())
var code = prompt('How to modify the name?', 'return name')
var fn = new Function('name', code)

try {

  var tasks = selection.map(function(item) {
    var name = item.name()
    try {
      var target = fn(name)
    } catch (e) {
      throw new Error('Cannot rename "' + name + '": ' + e)
    }
    if (!target) {
      throw new Error('Cannot rename "' + name + '": expression returned empty result')
    }
    return { item: item, from: name, to: target }
  }).filter(function(task) { return task.from != task.to })
  
  if (tasks.length == 0) throw new Error('No files to rename!')
  
  var message = 'These files will be renamed:\n\n' +
        tasks.map(function(task) { return '- ' + task.from + ' => ' + task.to }).join('\n')

  if (confirm(message)) {
    tasks.forEach(executeTask)
  }
  
} catch (e) {
  alert('Error!', String(e))
}

// Recipes from: https://github.com/dtinth/JXA-Cookbook/wiki/User-Interactions

function prompt(text, defaultAnswer) {
  var options = { defaultAnswer: defaultAnswer || '' }
  try {
    return app.displayDialog(text, options).textReturned
  } catch (e) {
    return null
  }
}

function alert(text, informationalText) {
  var options = { }
  if (informationalText) options.message = informationalText
  app.displayAlert(text, options)
}

function confirm(text) {
  try {
    app.displayDialog(text)
    return true
  } catch (e) {
    return false
  }
}

function executeTask(task) {
  task.item.name = task.to
}

doesn't work on my machine.
mid 2010 imac 10.10.3

I learning, a noob beginner. I cut and pasted the code. Gave it a directory and three files. It says there are no files.

Total newbie to JXA but not to javascript. Looking at:

var code = prompt('How to modify the name?', 'return name')
var fn = new Function('name', code)

Surely that sould be:

function fn () {
  return prompt('How to modify the name?');
}

@Ecclesiastes57
You should open finder with selecting some files,then run the script.It will work.

I'm not sure who wrote this script, but I first want to thank him/her for sharing. Much appreciated.

To deal with the issue above (you can expect a lot of JXA newbees), may I suggest:
(1) Add a section in the header comments for "How to Use"
(2) ADD a user selection validation test, and alert the user if no files have been selected in the Finder, and advise him/her that is required before running the script.
(3) You could also run the chooseFile method if the user does not make and Finder selections:

chooseFile
[withPrompt: text] : the prompt to be displayed in the dialog box
[ofType: list of text] : a list of file types or type identifiers. Only files of the specified types will be selectable.
[defaultLocation: alias] : the default file location
[invisibles: boolean] : Show invisible files and folders? (default is false)
[multipleSelectionsAllowed: boolean] : Allow multiple items to be selected? (default is false)
[showingPackageContents: boolean] : Show the contents of packages? (Packages will be treated as folders. Default is false.)
→ alias : the chosen file

I think you are already solved. But also if you need more facility with the batch name files- than kindly search on google by this keyword- BatchRenameFiles Tool. You will get the solve. I hope you will become happy by using the software of BatchRenameFiles Tool.

Thanks
Jonathan F.

Hi, I just stumbled upon this is snippet and it is truly awesome.

Would it be okay if I used it in my own (open source, non-commercial) project, of course with crediting? ( https://github.com/chrisgrieser/finder-vim-mode )

please feel free! @chrisgrieser