Sorry to be late on my own question. With the nightly of swift now which is available in docker swift includes format as a subcommand also on linux.
# Just do not use the -!
swift format -h
OVERVIEW: Format or lint Swift source code
USAGE: swift-format [--version] <subcommand>
OPTIONS:
-v, --version Print the version and exit
-h, --help Show help information.
SUBCOMMANDS:
dump-configuration Dump the default configuration in JSON format to standard output
format (default) Format Swift source code
lint Diagnose style issues in Swift source code
See 'swift-format help <subcommand>' for detailed help.
But the weird thing is that it is not listed as a sub command of the swift main command. This seams a bug?
swift -h
...
Subcommands:
swift build Build Swift packages
swift package Create and work on packages
swift run Run a program from a package
swift test Run package tests
swift repl Experiment with Swift code interactively
Use `swift --version` for Swift version information.
Use `swift --help` for descriptions of available options and flags.
Use `swift help <subcommand>` for more information about a subcommand.