Merge PR cosmos#4792: panic on non-registered store

* panic on non-registered store

* add pending

* cl

* Delete _4792-bpanic-on-retr

.pending/improvements/store/_4792-panic-non-regi

@@ -0,0 +1 @@
+#4792 panic on non-registered store

go.mod

@@ -6,6 +6,7 @@ require (
 	github.com/btcsuite/btcd v0.0.0-20190115013929-ed77733ec07d
 	github.com/cosmos/go-bip39 v0.0.0-20180618194314-52158e4697b8
 	github.com/cosmos/ledger-cosmos-go v0.10.3
+	github.com/cosmos/tools/cmd/clog v0.0.0-20190722180430-ea942c183cba // indirect
 	github.com/fortytw2/leaktest v1.3.0 // indirect
 	github.com/gogo/protobuf v1.2.1
 	github.com/golang/mock v1.3.1-0.20190508161146-9fa652df1129

go.sum

@@ -33,6 +33,8 @@ github.com/cosmos/ledger-cosmos-go v0.10.3 h1:Qhi5yTR5Pg1CaTpd00pxlGwNl4sFRdtK1J
 github.com/cosmos/ledger-cosmos-go v0.10.3/go.mod h1:J8//BsAGTo3OC/vDLjMRFLW6q0WAaXvHnVc7ZmE8iUY=
 github.com/cosmos/ledger-go v0.9.2 h1:Nnao/dLwaVTk1Q5U9THldpUMMXU94BOTWPddSmVB6pI=
 github.com/cosmos/ledger-go v0.9.2/go.mod h1:oZJ2hHAZROdlHiwTg4t7kP+GKIIkBT+o6c9QWFanOyI=
+github.com/cosmos/tools/cmd/clog v0.0.0-20190722180430-ea942c183cba h1:YhVnGzBkE2TvfBW5fAYBdNVK/3bwTPYVbMaOIGRHFRY=
+github.com/cosmos/tools/cmd/clog v0.0.0-20190722180430-ea942c183cba/go.mod h1:TdPuAVaU2rc6K24ejr/AnGznt9Fd2qjtMoRrTO4uFrI=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=
 github.com/davecgh/go-spew v0.0.0-20171005155431-ecdeabc65495/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

store/cachemulti/store.go

@@ -1,6 +1,7 @@
 package cachemulti
 
 import (
+	"fmt"
 	"io"
 
 	dbm "github.com/tendermint/tendermint/libs/db"
@@ -140,5 +141,9 @@ func (cms Store) GetStore(key types.StoreKey) types.Store {
 
 // GetKVStore returns an underlying KVStore by key.
 func (cms Store) GetKVStore(key types.StoreKey) types.KVStore {
-	return cms.stores[key].(types.KVStore)
+	store := cms.stores[key]
+	if key == nil {
+		panic(fmt.Sprintf("kv store with key %v has not been registered in stores", key))
+	}
+	return store.(types.KVStore)
 }