feat(x/gov): add MsgSubmitProposal SetMsgs method (backport #17387) (#17388)

Co-authored-by: Julien Robert <[email protected]>

Author: mergify[bot]

CHANGELOG.md

@@ -39,6 +39,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Improvements
 
+* (x/gov) [#17387](https://github.com/cosmos/cosmos-sdk/pull/17387) Add `MsgSubmitProposal` `SetMsgs` method. 
 * (x/gov) [#17354](https://github.com/cosmos/cosmos-sdk/issues/17354) Emit `VoterAddr` in `proposal_vote` event.
 * (x/genutil) [#17296](https://github.com/cosmos/cosmos-sdk/pull/17296) Add `MigrateHandler` to allow reuse migrate genesis related function.
     * In v0.46, v0.47 this function is additive to the `genesis migrate` command. However in v0.50+, adding custom migrations to the `genesis migrate` command is directly possible.

x/gov/types/v1/msgs.go

@@ -40,6 +40,18 @@ func (m *MsgSubmitProposal) GetMsgs() ([]sdk.Msg, error) {
 	return sdktx.GetMsgs(m.Messages, "sdk.MsgProposal")
 }
 
+// SetMsgs packs sdk.Msg's into m.Messages Any's
+// NOTE: this will overwrite any existing messages
+func (m *MsgSubmitProposal) SetMsgs(msgs []sdk.Msg) error {
+	anys, err := sdktx.SetMsgs(msgs)
+	if err != nil {
+		return err
+	}
+
+	m.Messages = anys
+	return nil
+}
+
 // Route implements Msg
 func (m MsgSubmitProposal) Route() string { return types.RouterKey }