Thanks to Attila Lendvai for catching a typo in the docstring.

Move from style-warning to warning with 3.3, not 3.2.1.

Deprecation goes through the following phases:
style-warning, warning, cerror, functionality removed.
Automatically upgrade the deprecation phase at every minor version change
(not every release).

Include minimal testing of the deprecation functionality.
Add deprecation TODO items.

Deprecation will start with 3.2.

Not used in Quicklisp.

A few are kept, for backward-compatibility with systems in quicklisp.

Rename functions accordingly.

Francois-Rene Rideau authored Mar 28, 2015 and Robert Goldman committed Apr 14, 2015

Fixes lp#1437480.
Also includes backward compatibility with previous not-so-portable API.

Based on a contribution by Christian Shafmeister.

1- To make life easier on Xach, stop requiring asdf.lisp to be loaded as source
before it's compiled. Instead, wrap each and every single form in an eval-when,
most of the time via the with-upgradability macro that also transforms
defun into defun* and defgeneric into defgeneric*.
Causes massive reindentation :-(

2- Have a proper :version for fallback systems.
Will make systems that check the version happier.

3- protect a condition with #+sb-eval. Fixes lp#1116408.

4- Protect warnings-file methods with dynamic when *warnings-file-type*
rather than static #+.

1- To make life easier on Xach, stop requiring asdf.lisp to be loaded as source
before it's compiled. Instead, wrap each and every single form in an eval-when,
most of the time via the with-upgradability macro that also transforms
defun into defun* and defgeneric into defgeneric*.
Causes massive reindentation :-(

2- Have a proper :version for fallback systems.
Will make systems that check the version happier.

3- protect a condition with #+sb-eval. Fixes lp#1116408.

4- Protect warnings-file methods with dynamic when *warnings-file-type*
rather than static #+.

A better asdf.asd.

Refactor the preloaded system mechanism, use it for cl-launch 3.21.2.

Rename bundle-pathname to build-pathname, move it from bundle-system to system.

Rename the gcl<2.7 feature gcl2.6. Die on gcl2.5 and earlier.
Don't even try to compile-file asdf using gcl 2.6, just load the .lisp.

Rename asdf/compatibility to asdf/common-lisp, exporting only CL symbols.
Fix define-package to correctly handle exporting of NIL.

Also, make it work with Genera, with #'(lambda instead of (lambda,
and using lisp:loop (via a macro loop*) when destructuring is required.

Document more 2.27 changes in changelog.

If there is no :pathname and no load-pathname,
do NOT have a system pathname take defaults from *default-pathname-defaults*,
but make it NIL.

Don't key upgrade attempt on source-registry, since things can also change
in the central-registry, etc.
Also rename required-files to direct-dependency-files
Improve the new convenience function pattern to work with operation initargs.
Implement getcwd on all platforms.
Actually catch sb-grovel messages.

Tests: make u l=ecl instead of make test-upgrade lisp=ecl
Tests: put the setup around the script, not inside;
Tests: start using globals, much easier for debugging

A system named foo/bar will be looked up in a registered file foo.asd.
This makes it possible to sensibly name several systems in a .asd file
and still have asdf find them all by name.
We now use it to not have the asdf header be part of asdf-driver.

A new generic operation build-op makes it possible to deal with
the fact that the default operation for systems need not be load-op,
yet that the end-user does not want to have to know the exact operation
for each of the system he uses.

ensure-pathname has been improved again, and its clients tweaked.

remove-keys was made more sensible by using EQL rather than STRING-EQUAL.

:version need not take the first form in a file, but can take
a path to a subform. This makes it possible to get the exact subform
in a Lisp source file that has the string.
See SUB-OBJECT for how these paths work.

Cleanup of the semantics of ENSURE-FUNCTION on CONSes: use APPLY, not EVAL.

Move things around and rename functions to improve backward compatibility.
The driver now has its own backward-compatibility file.