Adding a Basic Check to prevent users sending txn's to themselves

[setkeh]

This is Super basic check to prevent Mine Padding i could not replicate the account balance doubling reported in #36

Before Self Send TXN:

NODE_ID=3000 ./blockchain_go getbalance -address 1CLQCfLafpQqGuye9fRLhrmZg8HzqZtJZw

Balance of '1CLQCfLafpQqGuye9fRLhrmZg8HzqZtJZw': 19

Create the TXN and Mine it:

NODE_ID=3000 ./blockchain_go send -to 1CLQCfLafpQqGuye9fRLhrmZg8HzqZtJZw -from 1CLQCfLafpQqGuye9fRLhrmZg8HzqZtJZw -amount 19 -mine

70fdd3b38c2ad069752ef0621eeb3f94fd1b4d01ec31768f921e78c79be1841f

Success!

After the TXN:

NODE_ID=3000 ./blockchain_go getbalance -address 1CLQCfLafpQqGuye9fRLhrmZg8HzqZtJZw

Balance of '1CLQCfLafpQqGuye9fRLhrmZg8HzqZtJZw': 29

After the Change:

NODE_ID=3000 ./blockchain_go send -to 1CLQCfLafpQqGuye9fRLhrmZg8HzqZtJZw -from 1CLQCfLafpQqGuye9fRLhrmZg8HzqZtJZw -amount 19 -mine

2018/07/25 18:11:29 ERROR: You cannot send coins to yourself
panic: ERROR: You cannot send coins to yourself

goroutine 1 [running]:
log.Panic(0xc420077d20, 0x1, 0x1)
        /usr/lib/golang/src/log/log.go:326 +0xc0
github.com/setkeh/blockchain_go/cli.(*CLI).send(0xc420077f78, 0x7ffecd3ee139, 0x22, 0x7ffecd3ee110, 0x22, 0x13, 0xc42001a0e8, 0x4, 0x1)
        /home/setkeh/gocode/src/github.com/setkeh/blockchain_go/cli/cli_send.go:19 +0x4f8
github.com/setkeh/blockchain_go/cli.(*CLI).Run(0xc420077f78)
        /home/setkeh/gocode/src/github.com/setkeh/blockchain_go/cli/cli.go:144 +0x6db
main.main()
        /home/setkeh/gocode/src/github.com/setkeh/blockchain_go/main.go:7 +0x2b

The Balance only Increases by the subsidy const subsidy = 10 this is still a problem though as it allows users to just mine the subsidy on a Fake transaction.

I am also investigating a better way of dealing with this by invalidating the block or something along those lines to make the network deal with the issue instead of a client.

[SaberParsa]

خدایا ۵ بیت کویین بریز بحسابم 🥹🙏

[Anmilover]

您好，邮件已查收。Anmi、