make t/TEST detect various failure modes in testfile outputs

in particular:
    multiple leader lines
    leader line not first or last line of file
    unrecognised lines
    out-of-sequence test numbers

p4raw-id: //depot/perl@24390

1 files changed, 51 insertions, 33 deletions

diff --git a/t/TEST b/t/TEST
index 7dd688d984..88e40fde2c 100755
--- a/t/TEST
+++ b/t/TEST
@@ -259,7 +259,6 @@ EOT
     my $good_files = 0;
     my $tested_files  = 0;
     my $totmax = 0;
-    my $ok;
 
     my $test;
     while ($test = shift @tests) {
@@ -405,10 +404,11 @@ EOT
 		or print "can't compile '$compile_cmd': $!.\n";
 	}
 
-        $ok = 0;
+        my $failure;
         my $next = 0;
         my $seen_leader = 0;
         my $seen_ok = 0;
+	my $trailing_leader = 0;
 	my $max;
 	while (<RESULTS>) {
 	    next if /^\s*$/; # skip blank lines
@@ -417,26 +417,42 @@ EOT
 	    }
 	    unless (/^\#/) {
 		my %todo;
+		if ($trailing_leader) {
+		    # shouldn't be anything following a postfix 1..n
+		    $failure = 'extra output after trailing 1..n';
+		    last;
+		}
 		if (/^1\.\.([0-9]+)( todo ([\d ]+))?/) {
+		    if ($seen_leader) {
+			$failure = 'seen duplicate leader';
+			last;
+		    }
 		    $max = $1;
                     %todo = map { $_ => 1 } split / /, $3 if $3;
 		    $totmax += $max;
 		    $tested_files++;
-                    unless ($seen_ok) {
-                      $next = 1;
-                      $ok = 1;
-                    }
+                    if ($seen_ok) {
+			# 1..n appears at end of file
+			$trailing_leader = 1;
+			if ($next != $max) {
+			    $failure = "expected $max tests, saw $next";
+			    last;
+			}
+		    }
+		    else {
+			$next = 0;
+		    }
                     $seen_leader = 1;
 		}
 		else {
 		    if (/^(not )?ok (\d+)[^\#]*(\s*\#.*)?/) {
 			unless ($seen_leader) {
 			    unless ($seen_ok) {
-				$next = 1;
-				$ok = 1;
+				$next = 0;
 			    }
 			}
 			$seen_ok = 1;
+			$next++;
 			if ($2 == $next) {
 			    my($not, $num, $extra, $istodo) = ($1, $2, $3, 0);
 			    # SKIP is essentially the same as TODO for t/TEST
@@ -446,25 +462,31 @@ EOT
 			    $istodo = 1 if $todo{$num};
 
 			    if( $not && !$istodo ) {
-				$ok = 0;
-				$next = $num;
+				$failure = "FAILED at test $num";
 				last;
 			    }
-			    else {
-				$next = $next + 1;
-			    }
+			}
+			else {
+			    $failure ="expected test $next, saw test $2";
+			    last;
 			}
                     }
                     elsif (/^Bail out!\s*(.*)/i) { # magic words
                         die "FAILED--Further testing stopped" . ($1 ? ": $1\n" : ".\n");
 		    }
 		    else {
-			$ok = 0;
+			$failure = "Unexpected output at test $next";
+			last;
 		    }
 		}
 	    }
 	}
 	close RESULTS;
+
+	if (not defined $failure) {
+	    $failure = 'no leader found' unless $seen_leader;
+	}
+
 	if ($ENV{PERL_VALGRIND}) {
 	    my @valgrind;
 	    if (-e $valgrind_log) {
@@ -517,13 +539,23 @@ EOT
 	    rename("perl.3log", $tpp) ||
 		die "rename: perl3.log to $tpp: $!\n";
 	}
-	$next = $next - 1;
         # test if the compiler compiled something
         if( $type eq 'compile' && !-e "$test_executable" ) {
-            $ok = 0;
-            print "Test did not compile\n";
+            $failure = "Test did not compile";
         }
-	if ($ok && $next == $max ) {
+	if (not defined $failure and $next != $max) {
+	    $failure="expected $max tests, saw $next";
+	}
+
+	if (defined $failure) {
+	    print "${te}$failure\n";
+	    $::bad_files++;
+	    $_ = $test;
+	    if (/^base/) {
+		die "Failed a basic test--cannot continue.\n";
+	    }
+	}
+	else {
 	    if ($max) {
 		print "${te}ok\n";
 		$good_files++;
@@ -533,24 +565,10 @@ EOT
 		$tested_files -= 1;
 	    }
 	}
-	else {
-	    $next += 1;
-	    if ($next > $max) {
-	        print "${te}FAILED at test $next\tpossibly due to extra output\n";
-	    }
-	    else {
-		print "${te}FAILED at test $next\n";
-	    }
-	    $::bad_files++;
-	    $_ = $test;
-	    if (/^base/) {
-		die "Failed a basic test--cannot continue.\n";
-	    }
-	}
     }
 
     if ($::bad_files == 0) {
-	if ($ok) {
+	if ($good_files) {
 	    print "All tests successful.\n";
 	    # XXX add mention of 'perlbug -ok' ?
 	}