debhelper modular buildsystems (try 3).

* New feature - when listing buildsystems, list their status too
  (auto/specified).
* Dh_Buildsystem_Basic.pm renamed to Dh_Buildsystem.pm
* Addressed a few issues expressed in the comments, answered a few
  comments.
* Cache DEB_BUILD_GNU_TYPE value. Performance hit is noticable when
  listing build systems.
* is_auto_buildable() renamed to check_auto_buildable() (again).
  Since there is is_buildable() now, I didn't want to use is_ for
  that method.

Signed-off-by: Modestas Vainius <modestas@vainius.eu>

6 files changed, 26 insertions, 47 deletions

diff --git a/Debian/Debhelper/Buildsystem/autotools.pm b/Debian/Debhelper/Buildsystem/autotools.pm
index b94d8e17..74f1652e 100644
--- a/Debian/Debhelper/Buildsystem/autotools.pm
+++ b/Debian/Debhelper/Buildsystem/autotools.pm
@@ -15,9 +15,9 @@ sub DESCRIPTION {
 	"support for building GNU Autotools based packages"
 }
 
-sub is_auto_buildable {
+sub check_auto_buildable {
 	my $self=shift;
-	my $action=shift;
+	my ($action)=@_;
 
 	# Handle configure; the rest - next class
 	# XXX JEH 
@@ -30,6 +30,10 @@ sub is_auto_buildable {
 	# actions, it would use the methods inherited from its parent
 	# class. In the above example, that will try to run "make" w/o a
 	# Makefile, which prints a useful error.
+	# XXX MDX I'm all for it but this will differ from current dh_auto_build
+	#         behaviour (which is that dh_auto_build doesn't fail if
+	#         dh_auto_configure was not run). It is your call whether you are
+	#         willing to break this aspect of backwards compatibility.
 	if ($action eq "configure") {
 		return -x "configure";
 	}
diff --git a/Debian/Debhelper/Buildsystem/cmake.pm b/Debian/Debhelper/Buildsystem/cmake.pm
index ff248249..1b5dda40 100644
--- a/Debian/Debhelper/Buildsystem/cmake.pm
+++ b/Debian/Debhelper/Buildsystem/cmake.pm
@@ -14,11 +14,11 @@ sub DESCRIPTION {
 	"support for building CMake based packages (outside-source tree only)"
 }
 
-sub is_auto_buildable {
+sub check_auto_buildable {
 	my $self=shift;
 	my ($action)=@_;
 	my $ret = -e "CMakeLists.txt";
-	$ret &&= $self->SUPER::is_auto_buildable(@_) if $action ne "configure";
+	$ret &&= $self->SUPER::check_auto_buildable(@_) if $action ne "configure";
 	return $ret;
 }
 
diff --git a/Debian/Debhelper/Buildsystem/makefile.pm b/Debian/Debhelper/Buildsystem/makefile.pm
index 286f0f65..0595b0fa 100644
--- a/Debian/Debhelper/Buildsystem/makefile.pm
+++ b/Debian/Debhelper/Buildsystem/makefile.pm
@@ -8,7 +8,7 @@ package Debian::Debhelper::Buildsystem::makefile;
 
 use strict;
 use Debian::Debhelper::Dh_Lib;
-use base 'Debian::Debhelper::Dh_Buildsystem_Basic';
+use base 'Debian::Debhelper::Dh_Buildsystem';
 
 sub get_makecmd_C {
 	my $self=shift;
@@ -18,14 +18,6 @@ sub get_makecmd_C {
 	return $self->{makecmd};
 }
 
-# XXX JEH I *like* this. Yay for factoring out ugly ugly stuff!
-# XXX MDX TODO: this could use dh debian/rules parser.
-# XXX JEH That one checks for explicit only targets, while we want
-#         implicit targets here too. I think the current code is ok;
-#         it's a bonus that it checks if the target it empty.
-#         Hmm, one problem is that if a target exists but will run no
-#         commands since it's already built, the approach below will return
-#         nothing and assume it doesn't exist.
 sub exists_make_target {
 	my ($self, $target) = @_;
 	my $makecmd=$self->get_makecmd_C();
@@ -61,12 +53,14 @@ sub new {
 	return $self;
 }
 
-sub is_auto_buildable {
+sub check_auto_buildable {
 	my $self=shift;
 	my ($action) = @_;
 
 	# Handles build, test, install, clean; configure - next class
 	# XXX JEH shouldn't it also handle configure, just as a no-op?
+	# XXX MDX No, then cmake.mk would have no chance of hitting for
+	#         no good reason.
 	if (grep /^\Q$action\E$/, qw{build test install clean}) {
 		# This is always called in the source directory, but generally
 		# Makefiles are created (or live) in the the build directory.
diff --git a/Debian/Debhelper/Buildsystem/perl_build.pm b/Debian/Debhelper/Buildsystem/perl_build.pm
index 550f2a5b..63655304 100644
--- a/Debian/Debhelper/Buildsystem/perl_build.pm
+++ b/Debian/Debhelper/Buildsystem/perl_build.pm
@@ -8,13 +8,13 @@ package Debian::Debhelper::Buildsystem::perl_build;
 
 use strict;
 use Debian::Debhelper::Dh_Lib;
-use base 'Debian::Debhelper::Dh_Buildsystem_Basic';
+use base 'Debian::Debhelper::Dh_Buildsystem';
 
 sub DESCRIPTION {
 	"support for building Perl Build.PL based packages (in-source only)"
 }
 
-sub is_auto_buildable {
+sub check_auto_buildable {
 	my ($self, $action) = @_;
 
 	# Handles everything
@@ -25,6 +25,8 @@ sub is_auto_buildable {
 	# succeed, silently do nothing. Perhaps it would be better, then,
 	# to omit the test below. Then, it would try to run ./Build
 	# which doesn't exist, which should result in a semi-useful error.
+	# XXX MDX Agreed. But it would not be fully backwards compatible
+	#         (see comment in autotools.mk why). Your call.
 	if ($action ne "configure") {
 		$ret &&= -e "Build";
 	}
diff --git a/Debian/Debhelper/Buildsystem/perl_makemaker.pm b/Debian/Debhelper/Buildsystem/perl_makemaker.pm
index 91a0da3d..29570166 100644
--- a/Debian/Debhelper/Buildsystem/perl_makemaker.pm
+++ b/Debian/Debhelper/Buildsystem/perl_makemaker.pm
@@ -14,23 +14,19 @@ sub DESCRIPTION {
 	"support for building Perl MakeMaker based packages (in-source only)"
 }
 
-sub is_auto_buildable {
-	my ($self, $action)=@_;
+sub check_auto_buildable {
+	my $self=shift;
+	my ($action)=@_;
 
 	# Handles configure, install; the rest - next class
 	if ($action eq "install") {
-		# This hack is needed to keep full 100% compatibility with previous
-		# debhelper versions.
-		# XXX JEH perl_makemaker comes before makefile, so
-		# couldn't it instead just test for Makefile.PL?
-		if (-e "Makefile" &&
-		    system('grep -q "generated automatically by MakeMaker" Makefile') == 0) {
-			return 1;
-		}
+		return -e "Makefile.PL";
 	}
 	# XXX JEH why test for configure here? If building or cleaning, and
 	# a Makefile.PL exists, we know this class can handle those
 	# actions -- it does so by inheriting from the makefile class.
+	# XXX MDX Yes. But that's again different behaviour from current
+	#         (see comment in autotools.mk). Your call.
 	elsif ($action eq "configure") {
 		return -e "Makefile.PL";
 	}
@@ -57,15 +53,7 @@ sub configure {
 sub install {
 	my $self=shift;
 	my $destdir=shift;
-	# XXX JEH this test seems redundant with the one in
-	# is_auto_buildable, if we get here we know that one succeeded.
-	if (-e "Makefile" &&
-	    system('grep -q "generated automatically by MakeMaker" Makefile') == 0) {
-		$self->SUPER::install($destdir, "PREFIX=/usr", @_);
-	}
-	else {
-		$self->SUPER::install($destdir, @_);
-	}
+	$self->SUPER::install($destdir, "PREFIX=/usr", @_);
 }
 
 1;
diff --git a/Debian/Debhelper/Buildsystem/python_distutils.pm b/Debian/Debhelper/Buildsystem/python_distutils.pm
index 0b8367ec..0061a442 100644
--- a/Debian/Debhelper/Buildsystem/python_distutils.pm
+++ b/Debian/Debhelper/Buildsystem/python_distutils.pm
@@ -9,23 +9,14 @@ package Debian::Debhelper::Buildsystem::python_distutils;
 
 use strict;
 use Debian::Debhelper::Dh_Lib;
-use base 'Debian::Debhelper::Dh_Buildsystem_Basic';
+use base 'Debian::Debhelper::Dh_Buildsystem';
 
 sub DESCRIPTION {
 	"support for building Python distutils based packages"
 }
 
-sub is_auto_buildable {
-	my $self=shift;
-	my $action=shift;
-
-	# Handle build install clean; the rest - next class
-	# XXX JEH shouldn't it also handle configure? It would be handled
-	# by doing nothing, but that's what's appropriate for python.
-	if (grep(/^\Q$action\E$/, qw{build install clean})) {
-		return -e "setup.py";
-	}
-	return 0;
+sub check_auto_buildable {
+	return -e "setup.py";
 }
 
 sub setup_py {