Smarter handling of revlog key errors
Use RevlogError for reporting exceptions
Catch and report RevlogError exceptions at the command parser
#!/bin/sh
hg init
echo a > a
hg add a
hg commit -m "test" -d "0 0"
hg history
hg tag -d "0 0" "bleah"
hg history
echo foo >> .hgtags
hg tag -d "0 0" "bleah2" || echo "failed"