Are the blocks mined by a wallet shown as transaction?

Question

How can one be sure that a wallet address has mined 1 or more xmr blocks?
Do they show as transactions or is there any way to confirm?
I ran a wallet with monero wallet cli and upon running show_transfers commands it returned nothing
Does this guarantee this wallet has never mined any block or done any transaction?
(Pardon my naivety I am totally new to xmr)

Answer 1

They do show as transactions. Special types of transaction with a dummy input (since noone's actually spending any monero) and one or more outputs (usually just one, pre-rct coinbase transactions have more than one).

Example on testnet:

Height 1635197, txid <0e74095b092051a9742a36a09b6a550137132504579101062ddb2e973f837344>, 2.822135419737, idx 0/0
Height 1635198, txid <fced7485c1ee265132c5a910986b2c48b123f0c58609f61a107e7db73e4b71d8>, 2.822130036941, idx 0/0
Height 1635199, txid <775200145a2cd4891334c6181e07b9f1227b2213eb04265dc77b188210c8bdf0>, 2.822124654155, idx 0/0

These are all new blocks. With show_transfers, they show as "block" type rather than "in":

 1635197  block  40 blks       2021-01-19 14:20:31       2.822135419737 0e74095b092051a9742a36a09b6a550137132504579101062ddb2e973f837344 0000000000000000 0.000000000000 9yvGzysbcaWPHNjzkdKTMy5E7uvf85eNtZmuDQ3FLJrq3TeMy9cEaEi5CK7FqXNboWKHBvLGAxHFB5gq8KpSxmgJPah9MJc:2.822135419737 0 - 
 1635198  block  41 blks       2021-01-19 14:20:55       2.822130036941 fced7485c1ee265132c5a910986b2c48b123f0c58609f61a107e7db73e4b71d8 0000000000000000 0.000000000000 9yvGzysbcaWPHNjzkdKTMy5E7uvf85eNtZmuDQ3FLJrq3TeMy9cEaEi5CK7FqXNboWKHBvLGAxHFB5gq8KpSxmgJPah9MJc:2.822130036941 0 - 
 1635199  block  42 blks       2021-01-19 14:20:55       2.822124654155 775200145a2cd4891334c6181e07b9f1227b2213eb04265dc77b188210c8bdf0 0000000000000000 0.000000000000 9yvGzysbcaWPHNjzkdKTMy5E7uvf85eNtZmuDQ3FLJrq3TeMy9cEaEi5CK7FqXNboWKHBvLGAxHFB5gq8KpSxmgJPah9MJc:2.822124654155 0 - 

If show_transfers shows nothing, this is either because your wallet has not sent/received anything, or because it has not scanned the chain (or only part of the chain).