t/test.pl - assign caller() to separate vars in _where()

_where() is a heavily used, small subroutine within test.pl. It currently
assigns all eleven of caller()'s return values to array elements, then
uses only the second and third of these to construct a return string.

This commit changes the assignment to use separate variables, which ends
up being more efficient.

Benchmarking suggests that _where() is about 30% faster as a result.
The overhead of ok( ... ) calls is reduced by about 10%.

1 files changed, 2 insertions, 2 deletions

diff --git a/t/test.pl b/t/test.pl
index 2c4690834c..fdf7d594fa 100644
--- a/t/test.pl
+++ b/t/test.pl
@@ -274,8 +274,8 @@ sub _ok {
 }
 
 sub _where {
-    my @caller = caller($Level);
-    return "at $caller[1] line $caller[2]";
+    my (undef, $filename, $lineno) = caller($Level);
+    return "at $filename line $lineno";
 }
 
 # DON'T use this for matches. Use like() instead.