fix: Added missing validator key save when recovering from mnemonic (#9638)

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This PR adds a missing save inside the `InitializeNodeValidatorFilesFromMnemonic` method. 
Without it when using `gaiad init <name> --recover` no `priv_validator_key.json` file is created.

Closes: #XXXX

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- [ ] added a changelog entry to `CHANGELOG.md`
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CHANGELOG.md

@@ -76,7 +76,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (types) [\#9627](https://github.com/cosmos/cosmos-sdk/pull/9627) Fix nil pointer panic on `NewBigIntFromInt`
 * (x/genutil) [\#9574](https://github.com/cosmos/cosmos-sdk/pull/9575) Actually use the `gentx` client tx flags (like `--keyring-dir`)
 * (x/distribution) [\#9599](https://github.com/cosmos/cosmos-sdk/pull/9599) Withdraw rewards event now includes a value attribute even if there are 0 rewards (due to situations like 100% commission).
-
+* (x/genutil) [\#9638](https://github.com/cosmos/cosmos-sdk/pull/9638) Added missing validator key save when recovering from mnemonic
 
 ## [v0.43.0-rc0](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.43.0-rc0) - 2021-06-25
 

x/genutil/utils.go

@@ -54,7 +54,7 @@ func InitializeNodeValidatorFiles(config *cfg.Config) (nodeID string, valPubKey
 	return InitializeNodeValidatorFilesFromMnemonic(config, "")
 }
 
-// InitializeNodeValidatorFiles creates private validator and p2p configuration files using the given mnemonic.
+// InitializeNodeValidatorFilesFromMnemonic creates private validator and p2p configuration files using the given mnemonic.
 // If no valid mnemonic is given, a random one will be used instead.
 func InitializeNodeValidatorFilesFromMnemonic(config *cfg.Config, mnemonic string) (nodeID string, valPubKey cryptotypes.PubKey, err error) {
 	if len(mnemonic) > 0 && !bip39.IsMnemonicValid(mnemonic) {
@@ -84,6 +84,7 @@ func InitializeNodeValidatorFilesFromMnemonic(config *cfg.Config, mnemonic strin
 	} else {
 		privKey := tmed25519.GenPrivKeyFromSecret([]byte(mnemonic))
 		filePV = privval.NewFilePV(privKey, pvKeyFile, pvStateFile)
+		filePV.Save()
 	}
 
 	tmValPubKey, err := filePV.GetPubKey()

x/genutil/utils_test.go

@@ -2,6 +2,8 @@ package genutil
 
 import (
 	"encoding/json"
+	tmed25519 "github.com/tendermint/tendermint/crypto/ed25519"
+	"github.com/tendermint/tendermint/privval"
 	"os"
 	"path/filepath"
 	"testing"
@@ -57,6 +59,13 @@ func TestInitializeNodeValidatorFilesFromMnemonic(t *testing.T) {
 				require.Error(t, err)
 			} else {
 				require.NoError(t, err)
+
+				if tt.mnemonic != "" {
+					actualPVFile := privval.LoadFilePV(cfg.PrivValidatorKeyFile(), cfg.PrivValidatorStateFile())
+					expectedPrivateKey := tmed25519.GenPrivKeyFromSecret([]byte(tt.mnemonic))
+					expectedFile := privval.NewFilePV(expectedPrivateKey, cfg.PrivValidatorKeyFile(), cfg.PrivValidatorStateFile())
+					require.Equal(t, expectedFile, actualPVFile)
+				}
 			}
 		})
 	}