[interchange] Tag import-fields: make error handling more robust

commit ff51f5720164b94d02369791d139a38430f7e235
Author: Jon Jensen <[email protected]>
Date:   Wed Nov 1 18:56:30 2017 -0600

    Tag import-fields: make error handling more robust
    
    Some database types' set_slice do not eval, and thus do not reliably
    set $@ so we should clear it first.
    
    Include $@ if it is set. This is still messy, because an unrelated eval
    in set_slice or something it calls could leave a bogus error, but without
    rewriting every set_slice completely, this is the best we can do.
    
    The set_slice method returns undef on failure or a new key on success,
    so check for that instead.

 code/UI_Tag/import_fields.coretag |   21 +++++++++++++--------
 1 files changed, 13 insertions(+), 8 deletions(-)
---
diff --git a/code/UI_Tag/import_fields.coretag b/code/UI_Tag/import_fields.coretag
index 11848e8..b7cedf9 100644
--- a/code/UI_Tag/import_fields.coretag
+++ b/code/UI_Tag/import_fields.coretag
@@ -1,4 +1,4 @@
-# Copyright 2002-2007 Interchange Development Group and others
+# Copyright 2002-2009 Interchange Development Group and others
 # 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -7,7 +7,7 @@
 
 UserTag import_fields Order   table
 UserTag import_fields addAttr
-UserTag import_fields Version $Revision: 1.15 $
+UserTag import_fields Version 1.16
 UserTag import_fields Routine <<EOR
 sub {
 	my($table, $opt) = @_;
@@ -421,13 +421,18 @@ EOF
 			}
 		}
 
-		$db->set_slice($k, \%hash) if @names;
+		if (@names) {
+			undef $@;
+			my $key = $db->set_slice($k, \%hash);
+			unless ($key) {
+				my $msg_raw = "error on update";
+				$msg_raw .= ": $@" if $@;
+				my $msg = ::errmsg($msg_raw);
+				::logError($msg);
+				$out .= $msg;
+			}
+		}
 
-		if($@) {
-   			my $msg = ::errmsg("error on update: %s", $@);
-			::logError($msg);
-   			$out .= $msg;
-   		}
 		$count++;
 	}