[WIP] Create NQP version of check-versions.pl

Unfinished.

tools/build/check-versions.nqp

@@ -0,0 +1,74 @@
+#!nqp
+# Copyright (C) 2014, The Perl Foundation.
+
+sub read_config($prog) {
+    my $tmpfile := nqp::sha(nqp::time_i());
+
+    nqp::shell("$prog --show-config  > $tmpfile 2>&1", nqp::cwd(), nqp::getenvhash());
+    my $fh := open($tmpfile, :r);
+    my %config;
+    while my $line := nqp::readlinefh($fh) {
+        my @match := $line ~~ / ^ (<-[ \s = ]>+) '=' (.*) /;
+        %config{@match[0]} := @match[1] if ?@match;
+    }
+    close($fh);
+    unlink($tmpfile);
+    return %config;
+}
+
+# TODO test this!
+sub parse_revision($rev) {
+    my $sep := regex { <[_.]> };
+    my @matches := $rev ~~ / (\d+) $sep (\d+) [ $sep (\d+) ]?[ '-' (\d+) '-g' <[0..9a..f]>* ]?$ /;
+    return @matches;
+}
+
+# TODO test this!
+sub cmp_rev($rev-a, $rev-b) {
+    my @a := parse-revision($rev-a);
+    my @b := parse-revision($rev-b);
+    my $cmp := 0;
+    for 0..3 -> $i {
+        $cmp := nqp::cmp_i(@a[$i],@b[$i]);
+        last if $cmp;
+    }
+    return $cmp;
+}
+
+sub MAIN(*@ARGS) {
+    my $m1 := nqp::stat('Makefile', nqp::const::STAT_MODIFYTIME);
+    my $m2 := nqp::stat('tools/build/Makefile-Parrot.in', nqp::const::STAT_MODIFYTIME);
+    if $m1 > $m2 {
+        nqp::die(qq«
+Makefile is older than tools/build/Makefile-Parrot.in, run something like
+
+    perl Configure.pl
+
+with --help or options as needed
+
+»);
+    }
+
+    my %nqp-config := read_config(@ARGS[0]);
+    my $nqp-have := %nqp-config<nqp::version> || '';
+    my $nqp-revision = slurp('tools/build/NQP_REVISION')
+    $nqp-revision := subst($nqp-revision, / \n $ /, '');
+    my @nqp-want := split(' ', $nqp-revision);
+    my $nwp-want := @nqp-want[0];
+
+    if !$nqp_have || cmp_rev($nqp_have, $nqp_want) < 0 {
+        my $parrot-option := '--gen-parrot or --prefix=$prefix';
+        if nqp::stat('install/bin/parrot', nqp::const::STAT_ISEXECUTABLE) {     # TODO Make this work!
+            my $path := abs_path;                                               # TODO create abs_path
+            $parrot-option := "--prefix=$path/install";
+        }
+        nqp::die(qq«
+NQP $nqp_have is too old ($nqp_want required), run something like
+
+    perl Configure.pl --gen-nqp $parrot_option
+
+»);
+    }
+
+    return 1;
+}