Getting an overview of all targets accumulated in a Phing build file

Looking for an equivalent to Ant's -p(rojecthelp) command-line option in Phing, I dug up that you can use Phing's -l(ist) option to get a quick overview of all targets hosted in a given build file. This comes in handy when you are maintaining build files or have to get a raw picture of the provided targets of a project specific build file. The following console output shows the targets hosted in a example build file. As you will see, by using the -l command-line option you get an overview of the default target, the main targets and further subtargets.

triton:work stolt$ phing -l
Buildfile: /Volumes/USB DISK/work/build.xml
Build file for recordshelf project
Default target:
-------------------------------------------------------------------------------
 help                Displays the help for this build file

Main targets:
-------------------------------------------------------------------------------
 build               Builds the project
 clean               Removes data left over by former build
 cs-coding-standard  Runs the coding standard code inspection
 help                Display the help for this build file
 init                Initializes the build process
 layout              Creates the project layout for the build
 lint-project        Lints all code artifacts
 test-components     Runs the automated component tests
 test-integration    Runs the automated integration tests
 test-units          Runs the automated unit tests

Subtargets:
-------------------------------------------------------------------------------
 build-initial-model

A target becomes a main target when it has an non-empty description attribute, otherwise it will be a subtarget. This can be used to define the visibility and thereby 'callability' of targets, similar as you would do when defining access specifiers for class members of a PHP class. Main targets would become the public targets of your build file and all subtargets could be considered as private targets, which shouldn't be called directly as they might/should be used to provide specific helper functionality to public main targets or target wrappers. To definitively veto the call to a target, which never should be run directly via the Phing CLI(e.g. phing tragetname), just define an invalid target name(i.e. -build-initial-model instead of build-initial-model) so the Phing CLI will respond with an error and thereby not run the build file. The next console output shows the Phing CLI response when calling a private target.

triton:work stolt$ phing -build-initial-model
Unknown argument: -build-initial-model
phing [options] [target [target2 [target3] ...]]
Options:
  -h -help               print this message
  -l -list               list available targets in this project
  -v -version            print the version information and exit
  -q -quiet              be extra quiet
  -verbose               be extra verbose
  -debug                 print debugging information
  -logfile <file>        use given file for log
  -logger <classname>    the class which is to perform logging
  -f -buildfile <file>   use given buildfile
  -D<property>=<value>   use value for given property
  -find <file>           search for buildfile towards the root of the
                         filesystem and use it
  -inputhandler <file>   the class to use to handle user input

Report bugs to <dev@phing.tigris.org>

This post is somehow a partial and PHP flavoured remix of a post by Julian Simpson, who runs the build doctor blog and is also the author of the 'Refactoring Ant Build Files' contribution to the upcoming ThoughtWorks Anthology book.