Making --error-on-invalid-index the default behavior

[zubeyr94]

Hello, currently the default behavior in pg_repack is to repack tables even if tables have invalid indexes on them. Users can force pg_repack to error when there are invalid indexes on tables before they are repacked by providing -error-on-invalid-index parameter on pg_repack 1.5.0 and later versions.

However, repacking tables with invalid indexes would cause the index to be corrupted. As a safety feature it would make sense to make --error-on-invalid-index the default behavior and there could be an option like --warn-on-invalid-index or --no-error-on-invalid-index for users who want to keep the old behavior.

[MasahikoSawada]

However, repacking tables with invalid indexes would cause the index to be corrupted. As a safety feature it would make sense to make --error-on-invalid-index the default behavior

What do exactly mean by safety feature? It's right that invalid indexes could corrupted after repacking a table, but invalid indexes are not used unless they are reindexed.