How to show uncompressed total physical size in bytes of an HFS-compressed file or directory?

Question

Case in point: Apple's TextEdit at /Applications/TextEdit.app

If you calculate the physical size with echo "$(/usr/bin/du -k -d 0 /Applications/TextEdit.app | /usr/bin/awk '{print $1}') * 1024" | /usr/bin/bc -l you'll get (in my case on 10.11.6) a size of 4538368 bytes.

However, if you open the Info window in Finder, it'll tell you that the physical size is way bigger: 8.6 MB on disk, almost double the size.

It's clear why: Apple used HFS compression on TextEdit. Running the third-party tool afsctool (which you can install with Homebrew) produces this result:

/usr/local/bin/afsctool /Applications/TextEdit.app /Applications/TextEdit.app: Number of HFS+ compressed files: 693

Now, macOS obviously seems to know the uncompressed physical size, as evidenced by the size-on-disk value in the Finder's Info window.

My question is, if there is a command-line read-only way to get that info, i.e. a way to show:

(a) the uncompressed physical size (disk use) of a file that is HFS-compressed, i.e. a file for which /usr/bin/stat -f %f returns "32" (even though it's "524320" for some reason in TextEdit), and

(b) the uncompressed total physical size (disk use) of a directory or bundle that contains HFS compressed files.

Note: only macOS native commands should be used to calculate the size, while not using Spotlight-dependent data, e.g. from the mdls command, which is buggy and sometimes returns (null) for the kMDItemPhysicalSize key, aside from the fact that some users have disabled Spotlight altogether.

Answer 1

Use afsctool command with -v flag, for example:

$ afsctool -v README
README:
File is HFS+ compressed.
File size (uncompressed data fork; reported size by Mac OS 10.6+ Finder): 3046 bytes / 3 KB (kilobytes) / 3 KiB (kibibytes)
File size (compressed data fork - decmpfs xattr; reported size by Mac OS 10.0-10.5 Finder): 0 bytes / 0 KB (kilobytes) / 0 KiB (kibibytes)
File size (compressed data fork): 1427 bytes / 1 KB (kilobytes) / 1 KiB (kibibytes)
Compression savings: 53.2%
Number of extended attributes: 0
Total size of extended attribute data: 0 bytes
Approximate overhead of extended attributes: 268 bytes
Approximate total file size (compressed data fork + EA + EA overhead + file overhead): 1943 bytes / 2 KB (kilobytes) / 2 KiB (kibibytes)