replace errors.go with github.com/pkg/errors (2/2) (#3890)

* init of (2/2) common errors

* Remove instances of cmn.Error (2/2)

- Replace usage of cmnError and errorWrap
- ref #3862

Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>

* comment wording

* simplify IsErrXXX functions

* log panic along with stopping the MConnection

lite/proxy/errors.go

@@ -1,7 +1,7 @@
 package proxy
 
 import (
-	cmn "github.com/tendermint/tendermint/libs/common"
+	"github.com/pkg/errors"
 )
 
 type errNoData struct{}
@@ -12,13 +12,10 @@ func (e errNoData) Error() string {
 
 // IsErrNoData checks whether an error is due to a query returning empty data
 func IsErrNoData(err error) bool {
-	if err_, ok := err.(cmn.Error); ok {
-		_, ok := err_.Data().(errNoData)
-		return ok
-	}
-	return false
+	_, ok := errors.Cause(err).(errNoData)
+	return ok
 }
 
 func ErrNoData() error {
-	return cmn.ErrorWrap(errNoData{}, "")
+	return errors.Wrap(errNoData{}, "")
 }

lite/proxy/query.go

@@ -4,9 +4,10 @@ import (
 	"fmt"
 	"strings"
 
-	cmn "github.com/tendermint/tendermint/libs/common"
+	"github.com/pkg/errors"
 
 	"github.com/tendermint/tendermint/crypto/merkle"
+	cmn "github.com/tendermint/tendermint/libs/common"
 	"github.com/tendermint/tendermint/lite"
 	lerr "github.com/tendermint/tendermint/lite/errors"
 	rpcclient "github.com/tendermint/tendermint/rpc/client"
@@ -83,7 +84,7 @@ func GetWithProofOptions(prt *merkle.ProofRuntime, path string, key []byte, opts
 		kp = kp.AppendKey(resp.Key, merkle.KeyEncodingURL)
 		err = prt.VerifyValue(resp.Proof, signedHeader.AppHash, kp.String(), resp.Value)
 		if err != nil {
-			return nil, cmn.ErrorWrap(err, "Couldn't verify value proof")
+			return nil, errors.Wrap(err, "Couldn't verify value proof")
 		}
 		return &ctypes.ResultABCIQuery{Response: resp}, nil
 	} else {
@@ -92,7 +93,7 @@ func GetWithProofOptions(prt *merkle.ProofRuntime, path string, key []byte, opts
 		// XXX How do we encode the key into a string...
 		err = prt.VerifyAbsence(resp.Proof, signedHeader.AppHash, string(resp.Key))
 		if err != nil {
-			return nil, cmn.ErrorWrap(err, "Couldn't verify absence proof")
+			return nil, errors.Wrap(err, "Couldn't verify absence proof")
 		}
 		return &ctypes.ResultABCIQuery{Response: resp}, nil
 	}

lite/proxy/verifier.go

@@ -1,7 +1,8 @@
 package proxy
 
 import (
-	cmn "github.com/tendermint/tendermint/libs/common"
+	"github.com/pkg/errors"
+
 	log "github.com/tendermint/tendermint/libs/log"
 	"github.com/tendermint/tendermint/lite"
 	lclient "github.com/tendermint/tendermint/lite/client"
@@ -29,11 +30,11 @@ func NewVerifier(chainID, rootDir string, client lclient.SignStatusClient, logge
 		logger.Info("lite/proxy/NewVerifier found no trusted full commit, initializing from source from height 1...")
 		fc, err := source.LatestFullCommit(chainID, 1, 1)
 		if err != nil {
-			return nil, cmn.ErrorWrap(err, "fetching source full commit @ height 1")
+			return nil, errors.Wrap(err, "fetching source full commit @ height 1")
 		}
 		err = trust.SaveFullCommit(fc)
 		if err != nil {
-			return nil, cmn.ErrorWrap(err, "saving full commit to trusted")
+			return nil, errors.Wrap(err, "saving full commit to trusted")
 		}
 	}