Still buggy findgteprime, fix from Eric Joanis <joanis@cs.toronto.edu>.

p4raw-id: //depot/perl@8128

2 files changed, 21 insertions, 7 deletions

diff --git a/lib/Tie/SubstrHash.pm b/lib/Tie/SubstrHash.pm
index 3b92bd1cee..afe5d8dc25 100644
--- a/lib/Tie/SubstrHash.pm
+++ b/lib/Tie/SubstrHash.pm
@@ -186,19 +186,21 @@ sub ceil {
 sub findgteprime { # find the smallest prime integer greater than or equal to
     use integer;
 
+# It may be sufficient (and more efficient, IF IT IS CORRECT) to use
+# $max = 1 + int sqrt $num and calculate it once only, but is it correct?
+
     my $num = ceil(shift);
     return 2 if $num <= 2;
 
     $num++ unless $num % 2;
 
-    my $max = int sqrt $num;
-
   NUM:
     for (;; $num += 2) {
-	for ($i = 3; $i <= $max; $i += 2) {
-	    next NUM unless $num % $i;
-	}
-	return $num;
+        my $max = int sqrt $num;
+        for ($i = 3; $i <= $max; $i += 2) {
+            next NUM unless $num % $i;
+        }
+        return $num;
     }
 }
 
diff --git a/t/lib/tie-substrhash.t b/t/lib/tie-substrhash.t
index d21ca0ab1b..8256db7b58 100644
--- a/t/lib/tie-substrhash.t
+++ b/t/lib/tie-substrhash.t
@@ -7,7 +7,7 @@ BEGIN {
     push @INC, '../lib';
 }    
 
-print "1..16\n";
+print "1..20\n";
 
 use strict;
 
@@ -97,3 +97,15 @@ print "ok 15\n";
 print "not " unless Tie::SubstrHash::findgteprime(13.000001) == 17;
 print "ok 16\n";
 
+print "not " unless Tie::SubstrHash::findgteprime(114) == 127;
+print "ok 17\n";
+
+print "not " unless Tie::SubstrHash::findgteprime(1000) == 1009;
+print "ok 18\n";
+
+print "not " unless Tie::SubstrHash::findgteprime(1024) == 1031;
+print "ok 19\n";
+
+print "not " unless Tie::SubstrHash::findgteprime(10000) == 10007;
+print "ok 20\n";
+