ci: improve error checking (errcheck linter) (#11195)

## Description

Implements part of #7258

Check some of currently unchecked errors.

- [x] baseapp
- [x] client
- [x] codec
- [x] crypto
- [x] server
- [x] simapp
- [ ] snapshots
- [ ] store
- [x] testutil
- [ ] types
- [ ] modules

---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

simapp/export.go

@@ -2,6 +2,7 @@ package simapp
 
 import (
 	"encoding/json"
+	"fmt"
 	"log"
 
 	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
@@ -125,8 +126,16 @@ func (app *SimApp) prepForZeroHeightGenesis(ctx sdk.Context, jailAllowedAddrs []
 		if err != nil {
 			panic(err)
 		}
-		app.DistrKeeper.Hooks().BeforeDelegationCreated(ctx, delAddr, valAddr)
-		app.DistrKeeper.Hooks().AfterDelegationModified(ctx, delAddr, valAddr)
+
+		if err := app.DistrKeeper.Hooks().BeforeDelegationCreated(ctx, delAddr, valAddr); err != nil {
+			// never called as BeforeDelegationCreated always returns nil
+			panic(fmt.Errorf("error while incrementing period: %w", err))
+		}
+
+		if err := app.DistrKeeper.Hooks().AfterDelegationModified(ctx, delAddr, valAddr); err != nil {
+			// never called as AfterDelegationModified always returns nil
+			panic(fmt.Errorf("error while creating a new delegation period record: %w", err))
+		}
 	}
 
 	// reset context height
@@ -174,7 +183,10 @@ func (app *SimApp) prepForZeroHeightGenesis(ctx sdk.Context, jailAllowedAddrs []
 		counter++
 	}
 
-	iter.Close()
+	if err := iter.Close(); err != nil {
+		app.Logger().Error("error while closing the key-value store reverse prefix iterator: ", err)
+		return
+	}
 
 	_, err := app.StakingKeeper.ApplyAndReturnValidatorSetUpdates(ctx)
 	if err != nil {

simapp/sim_bench_test.go

@@ -5,6 +5,7 @@ import (
 	"os"
 	"testing"
 
+	"github.com/stretchr/testify/require"
 	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
 
 	simtypes "github.com/cosmos/cosmos-sdk/types/simulation"
@@ -25,11 +26,8 @@ func BenchmarkFullAppSimulation(b *testing.B) {
 	}
 
 	defer func() {
-		db.Close()
-		err = os.RemoveAll(dir)
-		if err != nil {
-			b.Fatal(err)
-		}
+		require.NoError(b, db.Close())
+		require.NoError(b, os.RemoveAll(dir))
 	}()
 
 	app := NewSimApp(logger, db, nil, true, map[int64]bool{}, DefaultNodeHome, FlagPeriodValue, MakeTestEncodingConfig(), EmptyAppOptions{}, interBlockCacheOpt())
@@ -75,11 +73,8 @@ func BenchmarkInvariants(b *testing.B) {
 	config.AllInvariants = false
 
 	defer func() {
-		db.Close()
-		err = os.RemoveAll(dir)
-		if err != nil {
-			b.Fatal(err)
-		}
+		require.NoError(b, db.Close())
+		require.NoError(b, os.RemoveAll(dir))
 	}()
 
 	app := NewSimApp(logger, db, nil, true, map[int64]bool{}, DefaultNodeHome, FlagPeriodValue, MakeTestEncodingConfig(), EmptyAppOptions{}, interBlockCacheOpt())

simapp/sim_test.go

@@ -66,7 +66,7 @@ func TestFullAppSimulation(t *testing.T) {
 	require.NoError(t, err, "simulation setup failed")
 
 	defer func() {
-		db.Close()
+		require.NoError(t, db.Close())
 		require.NoError(t, os.RemoveAll(dir))
 	}()
 
@@ -104,7 +104,7 @@ func TestAppImportExport(t *testing.T) {
 	require.NoError(t, err, "simulation setup failed")
 
 	defer func() {
-		db.Close()
+		require.NoError(t, db.Close())
 		require.NoError(t, os.RemoveAll(dir))
 	}()
 
@@ -144,7 +144,7 @@ func TestAppImportExport(t *testing.T) {
 	require.NoError(t, err, "simulation setup failed")
 
 	defer func() {
-		newDB.Close()
+		require.NoError(t, newDB.Close())
 		require.NoError(t, os.RemoveAll(newDir))
 	}()
 
@@ -211,7 +211,7 @@ func TestAppSimulationAfterImport(t *testing.T) {
 	require.NoError(t, err, "simulation setup failed")
 
 	defer func() {
-		db.Close()
+		require.NoError(t, db.Close())
 		require.NoError(t, os.RemoveAll(dir))
 	}()
 
@@ -256,7 +256,7 @@ func TestAppSimulationAfterImport(t *testing.T) {
 	require.NoError(t, err, "simulation setup failed")
 
 	defer func() {
-		newDB.Close()
+		require.NoError(t, newDB.Close())
 		require.NoError(t, os.RemoveAll(newDir))
 	}()
 

simapp/simd/cmd/testnet.go

@@ -519,9 +519,13 @@ func startTestnet(cmd *cobra.Command, args startArgs) error {
 		return err
 	}
 
-	testnet.WaitForHeight(1)
+	if _, err := testnet.WaitForHeight(1); err != nil {
+		return err
+	}
 	cmd.Println("press the Enter Key to terminate")
-	fmt.Scanln() // wait for Enter Key
+	if _, err := fmt.Scanln(); err != nil { // wait for Enter Key
+		return err
+	}
 	testnet.Cleanup()
 
 	return nil