more guidance to build rakudo

It shows examples what option can be passes, and it also mentiones
other backends than Parrot when someone tried to build for several
backends but did not supply the right flags.

1 files changed, 70 insertions, 22 deletions

diff --git a/Configure.pl b/Configure.pl
index 443456f..f2b223d 100644
--- a/Configure.pl
+++ b/Configure.pl
@@ -90,22 +90,32 @@ MAIN: {
     }
     else {
         for my $l (sort keys %letter_to_backend) {
-            if (-x "$prefix/bin/nqp-$l" || -x "$prefix/bin/nqp-$l.bat" || -x "$prefix/bin/nqp-$l.exe") {
+            # TODO: needs .exe/.bat magic on windows?
+            if (-x "$prefix/bin/nqp-$l") {
                 my $b = $letter_to_backend{$l};
                 print "Found $prefix/bin/nqp-$l (backend $b)\n";
                 $backends{$b} = 1;
                 $default_backend ||= $b;
             }
         }
+        if (exists $options{'gen-moar'}) {
+            $backends{moar} = 1;
+            $default_backend ||= 'moar';
+        }
+        if (exists $options{'gen-parrot'}) {
+            $backends{parrot} = 1;
+            $default_backend ||= 'parrot';
+        }
         unless (%backends) {
-            if (defined $options{'gen-moar'}) {
-                $backends{moar} = 1;
-                $default_backend = 'moar';
-            }
-            else {
-                $backends{parrot} = 1;
-                $default_backend = 'parrot';
-            }
+            die "No suitable nqp executables found! Please specify some --backends, or a --prefix that contains nqp-{p,j,m} executables\n\n"
+              . "Example to build for all backends (which will take a while):\n"
+              . "\tperl Configure.pl --backends=moar,parrot,jvm --gen-moar --gen-parrot\n\n"
+              . "Example to build for MoarVM only:\n"
+              . "\tperl Configure.pl --gen-moar\n\n"
+              . "Example to build for Parrot only:\n"
+              . "\tperl Configure.pl --gen-parrot\n\n"
+              . "Example to build for JVM only:\n"
+              . "\tperl Configure.pl --backends=jvm --gen-nqp\n\n";
         }
     }
 
@@ -155,6 +165,7 @@ MAIN: {
     my %impls = gen_nqp($nqp_want, prefix => $prefix, backends => join(',', sort keys %backends), %options);
 
     my @errors;
+    my %errors;
     if ($backends{parrot}) {
         my %nqp_config;
         if ($impls{parrot}{config}) {
@@ -179,18 +190,12 @@ MAIN: {
             if @errors;
         }
 
-        if (@errors && !defined $options{'gen-nqp'}) {
-            push @errors,
-            "\nTo automatically clone (git) and build a copy of NQP $nqp_want,",
-            "try re-running Configure.pl with the '--gen-nqp' or '--gen-parrot'",
-            "options.  Or, use '--prefix=' to explicitly",
-            "specify the path where the NQP and Parrot executable can be found that are use to build $lang.";
-        }
-
-        sorry(@errors) if @errors;
+        $errors{parrot}{'no gen-nqp'} = @errors && !defined $options{'gen-nqp'};
 
-        %config = (%nqp_config, %config);
-        print "Using $impls{parrot}{bin} (version $nqp_config{'nqp::version'}).\n";
+        unless (@errors) {
+            %config = (%nqp_config, %config);
+            print "Using $impls{parrot}{bin} (version $nqp_config{'nqp::version'}).\n";
+        }
     }
     if ($backends{jvm}) {
         $config{j_nqp} = $impls{jvm}{bin};
@@ -208,11 +213,54 @@ MAIN: {
             push @errors, "jvm::runtime.jars value not available from $bin --show-config.";
         }
 
-        sorry(@errors) if @errors;
+        $errors{jvm}{'no gen-nqp'} = @errors && !defined $options{'gen-nqp'};
+
+        unless (@errors) {
+            %config = (%nqp_config, %config);
+            print "Using $bin.\n";
+        }
+    }
+    if ($backends{moar}) {
+        $config{m_nqp} = $impls{moar}{bin};
+        $config{m_nqp} =~ s{/}{\\}g if $^O eq 'MSWin32';
+        my %nqp_config;
+        if ( $impls{moar}{config} ) {
+            %nqp_config = %{ $impls{moar}{config} };
+        }
+        else {
+            push @errors, "Unable to read configuration from NQP on MoarVM";
+        }
+
+        $errors{moar}{'no gen-nqp'} = @errors && !defined $options{'gen-nqp'};
 
-        print "Using $bin.\n";
+        unless (@errors) {
+            %config = (%nqp_config, %config);
+            print "Using $config{m_nqp} (version $nqp_config{'nqp::version'} / MoarVM $nqp_config{'moar::version'}).\n";
+        }
+    }
 
+    if ($errors{parrot}{'no gen-nqp'} || $errors{jvm}{'no gen-nqp'} || $errors{moar}{'no gen-nqp'}) {
+        my @options_to_pass;
+        push @options_to_pass, "--gen-parrot" if $backends{parrot};
+        push @options_to_pass, "--gen-moar"   if $backends{moar};
+        push @options_to_pass, "--gen-nqp"    unless @options_to_pass;
+        my $options_to_pass  = join ' ', @options_to_pass;
+        my $want_executables = $backends{parrot} && $backends{moar}
+                             ? ', Parrot and MoarVM'
+                             : $backends{parrot}
+                             ? ' and Parrot'
+                             : $backends{moar}
+                             ? ' and MoarVM'
+                             : '';
+        my $s1               = @options_to_pass > 1 ? 's' : '';
+        my $s2               = $want_executables    ? 's' : '';
+        push @errors,
+        "\nTo automatically clone (git) and build a copy of NQP $nqp_want,",
+        "try re-running Configure.pl with the '$options_to_pass' option$s1.",
+        "Or, use '--prefix=' to explicitly specify the path where the NQP$want_executables",
+        "executable$s2 can be found that are use to build $lang.";
     }
+    sorry(@errors) if @errors;
 
     fill_template_file('tools/build/Makefile.in', 'Makefile', %config);