chore(core/02-client): remove the legacy handler for 02-client. (#6777)

* chore(core/02-client): remove the legacy handler for 02-client.

* chore: add to changelog, docs.

* Update docs/docs/05-migrations/13-v8-to-v9.md

Co-authored-by: Carlos Rodriguez <carlos@interchain.io>

---------

Co-authored-by: Carlos Rodriguez <carlos@interchain.io>

CHANGELOG.md

@@ -62,6 +62,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (23-commmitment) [\#6644](https://github.com/cosmos/ibc-go/pull/6644) Introduce commitment/v2 `MerklePath` to include `repeated bytes` in favour of `repeated string`. This supports using merkle path keys which include non UTF-8 encoded runes.
 * (23-commmitment) [\#6633](https://github.com/cosmos/ibc-go/pull/6633) MerklePath has been changed to use `repeated bytes` in favour of `repeated strings`.
 * (apps/27-interchain-accounts) [\#6749](https://github.com/cosmos/ibc-go/pull/6749) The ICA controller `NewIBCMiddleware` constructor function sets by default the auth module to nil.
+* (core/02-client) [\#6777](https://github.com/cosmos/ibc-go/pull/6777) The `NewClientProposalHandler` of `02-client` has been removed.
 
 ### State Machine Breaking
 

docs/docs/05-migrations/13-v8-to-v9.md

@@ -20,7 +20,15 @@ There are four sections based on the four potential user groups of this document
 
 ## Chains
 
-- No relevant changes were made in this release.
+Chains will need to remove the route for the legacy proposal handler for `02-client` from their `app/app.go`:
+
+```diff
+// app.go
+govRouter.AddRoute(govtypes.RouterKey, govv1beta1.ProposalHandler).
+-       AddRoute(paramproposal.RouterKey, params.NewParamChangeProposalHandler(app.ParamsKeeper)).
+-       AddRoute(ibcclienttypes.RouterKey, ibcclient.NewClientProposalHandler(app.IBCKeeper.ClientKeeper))
++       AddRoute(paramproposal.RouterKey, params.NewParamChangeProposalHandler(app.ParamsKeeper))
+```
 
 ## IBC Apps
 
@@ -114,6 +122,7 @@ The base application is then set by default to nil and thus authentication is as
 - `UnmarshalPacketData` now takes in the context, portID, and channelID. This allows the packet data to be unmarshaled based on the channel version.
 - `Router` reference has been removed from IBC core keeper: [#6138](https://github.com/cosmos/ibc-go/pull/6138). Please use `PortKeeper.Router` instead.
 - The function `CreateLocalhostClient` has been removed. The localhost client is now stateless. 
+- The function `NewClientProposalHandler` has been removed. [#6777](https://github.com/cosmos/ibc-go/pull/6777).
 
 ### 02-client
 

e2e/tests/core/02-client/client_test.go

@@ -160,86 +160,6 @@ func (s *ClientTestSuite) TestScheduleIBCUpgrade_Succeeds() {
 	})
 }
 
-func (s *ClientTestSuite) TestClientUpdateProposal_Succeeds() {
-	t := s.T()
-	ctx := context.TODO()
-
-	var (
-		pathName           string
-		subjectClientID    string
-		substituteClientID string
-		// set the trusting period to a value which will still be valid upon client creation, but invalid before the first update
-		badTrustingPeriod = time.Second * 10
-	)
-
-	testName := t.Name()
-	relayer := s.CreateDefaultPaths(testName)
-
-	t.Run("create substitute client with correct trusting period", func(t *testing.T) {
-		// TODO: update when client identifier created is accessible
-		// currently assumes first client is 07-tendermint-0
-		substituteClientID = clienttypes.FormatClientIdentifier(ibcexported.Tendermint, 0)
-
-		pathName = s.GetPaths(testName)[0]
-	})
-
-	chainA, chainB := s.GetChains()
-	chainAWallet := s.CreateUserOnChainA(ctx, testvalues.StartingTokenAmount)
-
-	t.Run("create subject client with bad trusting period", func(t *testing.T) {
-		createClientOptions := ibc.CreateClientOptions{
-			TrustingPeriod: badTrustingPeriod.String(),
-		}
-
-		s.SetupClients(ctx, relayer, createClientOptions)
-
-		// TODO: update when client identifier created is accessible
-		// currently assumes second client is 07-tendermint-1
-		subjectClientID = clienttypes.FormatClientIdentifier(ibcexported.Tendermint, 1)
-	})
-
-	time.Sleep(badTrustingPeriod)
-
-	t.Run("update substitute client", func(t *testing.T) {
-		s.UpdateClients(ctx, relayer, pathName)
-	})
-
-	s.Require().NoError(test.WaitForBlocks(ctx, 1, chainA, chainB), "failed to wait for blocks")
-
-	t.Run("check status of each client", func(t *testing.T) {
-		t.Run("substitute should be active", func(t *testing.T) {
-			status, err := query.ClientStatus(ctx, chainA, substituteClientID)
-			s.Require().NoError(err)
-			s.Require().Equal(ibcexported.Active.String(), status)
-		})
-
-		t.Run("subject should be expired", func(t *testing.T) {
-			status, err := query.ClientStatus(ctx, chainA, subjectClientID)
-			s.Require().NoError(err)
-			s.Require().Equal(ibcexported.Expired.String(), status)
-		})
-	})
-
-	t.Run("pass client update proposal", func(t *testing.T) {
-		proposal := clienttypes.NewClientUpdateProposal(ibctesting.Title, ibctesting.Description, subjectClientID, substituteClientID)
-		s.ExecuteAndPassGovV1Beta1Proposal(ctx, chainA, chainAWallet, proposal)
-	})
-
-	t.Run("check status of each client", func(t *testing.T) {
-		t.Run("substitute should be active", func(t *testing.T) {
-			status, err := query.ClientStatus(ctx, chainA, substituteClientID)
-			s.Require().NoError(err)
-			s.Require().Equal(ibcexported.Active.String(), status)
-		})
-
-		t.Run("subject should be active", func(t *testing.T) {
-			status, err := query.ClientStatus(ctx, chainA, subjectClientID)
-			s.Require().NoError(err)
-			s.Require().Equal(ibcexported.Active.String(), status)
-		})
-	})
-}
-
 // TestRecoverClient_Succeeds tests that a governance proposal to recover a client using a MsgRecoverClient is successful.
 func (s *ClientTestSuite) TestRecoverClient_Succeeds() {
 	t := s.T()

modules/light-clients/08-wasm/testing/simapp/app.go

@@ -129,7 +129,6 @@ import (
 	ibctransferkeeper "github.com/cosmos/ibc-go/v8/modules/apps/transfer/keeper"
 	ibctransfertypes "github.com/cosmos/ibc-go/v8/modules/apps/transfer/types"
 	ibc "github.com/cosmos/ibc-go/v8/modules/core"
-	ibcclient "github.com/cosmos/ibc-go/v8/modules/core/02-client"
 	ibcclienttypes "github.com/cosmos/ibc-go/v8/modules/core/02-client/types"
 	ibcconnectiontypes "github.com/cosmos/ibc-go/v8/modules/core/03-connection/types"
 	porttypes "github.com/cosmos/ibc-go/v8/modules/core/05-port/types"
@@ -425,8 +424,7 @@ func NewSimApp(
 	// See: https://docs.cosmos.network/main/modules/gov#proposal-messages
 	govRouter := govv1beta1.NewRouter()
 	govRouter.AddRoute(govtypes.RouterKey, govv1beta1.ProposalHandler).
-		AddRoute(paramproposal.RouterKey, params.NewParamChangeProposalHandler(app.ParamsKeeper)).
-		AddRoute(ibcclienttypes.RouterKey, ibcclient.NewClientProposalHandler(app.IBCKeeper.ClientKeeper))
+		AddRoute(paramproposal.RouterKey, params.NewParamChangeProposalHandler(app.ParamsKeeper))
 	govConfig := govtypes.DefaultConfig()
 	/*
 		Example of setting gov params:

testing/simapp/app.go

@@ -121,7 +121,6 @@ import (
 	ibctransferkeeper "github.com/cosmos/ibc-go/v8/modules/apps/transfer/keeper"
 	ibctransfertypes "github.com/cosmos/ibc-go/v8/modules/apps/transfer/types"
 	ibc "github.com/cosmos/ibc-go/v8/modules/core"
-	ibcclient "github.com/cosmos/ibc-go/v8/modules/core/02-client"
 	ibcclienttypes "github.com/cosmos/ibc-go/v8/modules/core/02-client/types"
 	ibcconnectiontypes "github.com/cosmos/ibc-go/v8/modules/core/03-connection/types"
 	porttypes "github.com/cosmos/ibc-go/v8/modules/core/05-port/types"
@@ -416,8 +415,7 @@ func NewSimApp(
 	// See: https://docs.cosmos.network/main/modules/gov#proposal-messages
 	govRouter := govv1beta1.NewRouter()
 	govRouter.AddRoute(govtypes.RouterKey, govv1beta1.ProposalHandler).
-		AddRoute(paramproposal.RouterKey, params.NewParamChangeProposalHandler(app.ParamsKeeper)).
-		AddRoute(ibcclienttypes.RouterKey, ibcclient.NewClientProposalHandler(app.IBCKeeper.ClientKeeper))
+		AddRoute(paramproposal.RouterKey, params.NewParamChangeProposalHandler(app.ParamsKeeper))
 	govConfig := govtypes.DefaultConfig()
 	/*
 		Example of setting gov params: