wallet: do not store deployed contract script inside Contract account field

[AliceInHunterland]

Close #3348

[AnnaShaleva]

The logic of this PR is correct. TestSignMultisigTx fails because contract's witness (an empty one, actually) is not added to the parameter context and parameter context is not aware of contract witnesses while building the resulting tx witnesses:

neo-go/pkg/smartcontract/context/context.go

Lines 65 to 83 in 0b136c1

	// GetCompleteTransaction clears transaction witnesses (if any) and refills them with
	// signatures from the parameter context.
	func (c *ParameterContext) GetCompleteTransaction() (*transaction.Transaction, error) {
	tx, ok := c.Verifiable.(*transaction.Transaction)
	if !ok {
	return nil, errors.New("verifiable item is not a transaction")
	}
	if len(tx.Scripts) > 0 {
	tx.Scripts = tx.Scripts[:0]
	}
	for i := range tx.Signers {
	w, err := c.GetWitness(tx.Signers[i].Account)
	if err != nil {
	return nil, fmt.Errorf("can't create witness for signer #%d: %w", i, err)
	}
	tx.Scripts = append(tx.Scripts, *w)
	}
	return tx, nil
	}

@roman-khimov, currently we can't use neo-go wallet sign with contract accounts. We have #2670 for those contracts that have verify method with arguments. Do you think we need to support at least an empty case of verify method right now in neo-go wallet sign? We also need parameter context to still be compatible with the C# behaviour, thus need to check how C# node handles contract witness case in parameter context.

[AnnaShaleva]

contract's witness (an empty one, actually) is not added to the parameter context and parameter context is not aware of contract witnesses while building the resulting tx witnesses

That's not correct, everything is OK with this code, it can properly handle contract witness.

@AliceInHunterland, you need to explicitly set account's script to null when importing contract account, otherwise an old value of some real signature account's script will be used:

anna@kiwi:~/Documents/GitProjects/nspcc-dev/neo-go$ git diff
diff --git a/cli/wallet/wallet.go b/cli/wallet/wallet.go
index 12691683..116d5280 100644
--- a/cli/wallet/wallet.go
+++ b/cli/wallet/wallet.go
@@ -651,6 +651,7 @@ func importDeployed(ctx *cli.Context) error {
                return cli.NewExitError("contract has no `verify` method with boolean return", 1)
        }
        acc.Address = address.Uint160ToString(cs.Hash)
+       acc.Contract.Script = nil
        acc.Contract.Parameters = acc.Contract.Parameters[:0]
        for _, p := range md.Parameters {
                acc.Contract.Parameters = append(acc.Contract.Parameters, wallet.ContractParam{

[AnnaShaleva]

@AliceInHunterland, add this line, add some comment about it and adjust the commit message.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.16%. Comparing base (3c471f0) to head (bb2d060).

❗ Current head bb2d060 differs from pull request most recent head b4fdf8c

Please upload reports for the commit b4fdf8c to get more accurate results.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3470      +/-   ##
==========================================
+ Coverage   86.12%   86.16%   +0.04%     
==========================================
  Files         331      331              
  Lines       38476    38476              
==========================================
+ Hits        33137    33153      +16     
+ Misses       3809     3798      -11     
+ Partials     1530     1525       -5     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.