Keeping previous versions of a document you’re working on can be a great timesaver. Although I seldom restore files from backups, it’s far more frequent that I look back in a file’s versions to recover changed or removed contents. In most cases, those had changed so rapidly that even hourly backups didn’t capture them. Had those versions not been saved automatically by macOS, I would have wasted time trying to recreate them from scratch.

Although a great many apps now come with built-in version support, macOS doesn’t preserve those versions as well as it could. Duplicate a document with versions, save it as another document, or move it to a different volume, and all its versions are blown away. As I explained yesterday, versions don’t transfer in iCloud Drive either. This article explains how you can work around all those, how to ensure versions get backed up, and how you can create PDF documents with versions.

How versions work

Many apps now have built-in support to automatically save versions of documents you edit with them. The tell-tale sign is when the app has a Revert To command in its File menu, which opens the current document in a version browser resembling the Time Machine app.

Each time you save a document in those apps, the existing document is saved to a hidden and locked-down database at the root level of that volume, in the .DocumentRevisions-V100 folder. When you use the Revert To command to browse all versions, you can look back at all the versions of that document saved to that volume. You can then revert to an older version, or copy contents from an older version to the current one. As long as that document remains in its current volume, those versions will remain accessible. However, if that document is moved to a different volume, even on the same disk, those versions don’t move with it, but will be retained in the original volume until it’s deleted from there.

If you’ve been editing a document in your Documents folder and move it into iCloud Drive, which is actually a folder inside your Home Library folder, its versions will be preserved when you access it from the same Mac. However, other Macs connected to the same iCloud account won’t see those versions, as they remain on the original Mac and don’t get synced to iCloud Drive.

How to extend versions

Apps can’t access stored versions directly, but have to do that via macOS. The most compatible way for them to do that is to fetch previous versions from the volume version database. They can then save each version as a separate file, and reconstitute a document complete with its versions by adding those files back to a document’s versions in the volume’s database. That’s exactly what my free utilities Versatility and Revisionist do. Versatility is the simpler of the two to use here, while Revisionist adds more features including checking documents to see how many versions they already have stored in their volume database.

Archive versions

Simply drag and drop a file with saved versions onto Versatility’s window, and it will extract all its versions and save them as a series of numbered files in a folder. You can then copy or move that folder to any other location, where you can reconstitute the original document with all its versions intact.

Unarchive versions

Simply drag and drop a folder containing archived version files onto Versatility’s window, and it will reconstitute the original document with all its previous versions.

Versions in iCloud Drive

To preserve all versions in iCloud Drive and make them available to all that connect to that folder, move the document from its existing location in your Home folder, to the correct folder in iCloud Drive. Once it’s there:

1. Perform any editing necessary.
2. Archive. Drop the document onto Versatility’s window, and save that archive folder to the same location.
3. Move the original document elsewhere.

When you want to edit that document, particularly on another Mac, on that Mac:

1. Unarchive. Drop the archive folder onto Versatility’s window, and save the document to the same location.
2. Edit the document, saving whenever you want to create a new version.
3. When you’ve finished, save for the last time, and close the document.
4. Archive. Drop the document onto Versatility’s window, and save that archive folder to the same location.
5. Tidy up old archive folders and files.

That leaves the most recent archive folder, with composite versions written in the correct order, with the right timestamps, ready to be unarchived on the next Mac to edit that document. This may appear complicated, but once you have tried it out, it’s really a simple sequence to unarchive-edit-save-archive and hand over to the next editor.

Backing up versions

I’m not aware of any backup utility for macOS, including Time Machine, that backs up and preserves versions, although they are stored in local volume snapshots. However, all you have to do is archive the versions of important files into folders using Versatility, and back up those folders. When you want to restore the original document with all its versions, simply unarchive that folder using Versatility.

PDF versions

One of the lesser-known features of the PDF format are incremental updates, which can provide a primitive form of versioning within a single file. In practice it catches users out when they publish a PDF containing old edited content they thought had been removed.

Few PDF editors and viewers support the macOS version system, but Preview does, and Versatility can be used to assemble a PDF document with versions.

For my example, rather than edit a PDF, I generated a series from an archived RTF, converting each file into a consecutively numbered PDF, starting from 000.pdf and rising to 010.pdf. I then dropped that folder onto Versatility’s window and it unarchived those into a single PDF document with all those versions.

Key points

• Archive a file with saved versions to a folder by dropping it onto Versatility’s window.
• Unarchive a folder containing version files to a file with saved versions by dropping it onto Versatility’s window.
• In iCloud Drive, unarchive-edit-save-archive to preserve versions for the next editor.
• Wherever you want to preserve versions, archive the file using Versatility.