From a73b3f5e971a4473f1a6defd4f5a4ece3ac7b1b2 Mon Sep 17 00:00:00 2001
From: Ethan Frey <ethanfrey@users.noreply.github.com>
Date: Mon, 5 Aug 2019 20:17:37 +0200
Subject: [PATCH] Merge PR #4849: Result from error

---
 types/errors.go      | 32 ++++++++++++++++++++++++++++----
 types/errors_test.go | 42 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 70 insertions(+), 4 deletions(-)

diff --git a/types/errors.go b/types/errors.go
index e5c3b1a26b80..7a7a0d4a9dcd 100644
--- a/types/errors.go
+++ b/types/errors.go
@@ -7,9 +7,11 @@ import (
 	"strings"
 
 	"github.com/pkg/errors"
-	cmn "github.com/tendermint/tendermint/libs/common"
 
 	abci "github.com/tendermint/tendermint/abci/types"
+	cmn "github.com/tendermint/tendermint/libs/common"
+
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 )
 
 // CodeType - ABCI code identifier within codespace
@@ -248,10 +250,14 @@ func (err *sdkError) Code() CodeType {
 // Implements ABCIError.
 func (err *sdkError) ABCILog() string {
 	errMsg := err.cmnError.Error()
+	return encodeErrorLog(err.codespace, err.code, errMsg)
+}
+
+func encodeErrorLog(codespace CodespaceType, code CodeType, msg string) string {
 	jsonErr := humanReadableError{
-		Codespace: err.codespace,
-		Code:      err.code,
-		Message:   errMsg,
+		Codespace: codespace,
+		Code:      code,
+		Message:   msg,
 	}
 
 	var buff bytes.Buffer
@@ -282,6 +288,24 @@ func (err *sdkError) QueryResult() abci.ResponseQuery {
 	}
 }
 
+// ResultFromError will return err.Result() if it implements sdk.Error
+// Otherwise, it will use the reflecton from types/error to determine
+// the code, codespace, and log.
+//
+// This is intended to provide a bridge to allow both error types
+// to live side-by-side.
+func ResultFromError(err error) Result {
+	if sdk, ok := err.(Error); ok {
+		return sdk.Result()
+	}
+	space, code, log := sdkerrors.ABCIInfo(err, false)
+	return Result{
+		Codespace: CodespaceType(space),
+		Code:      CodeType(code),
+		Log:       encodeErrorLog(CodespaceType(space), CodeType(code), log),
+	}
+}
+
 //----------------------------------------
 // REST error utilities
 
diff --git a/types/errors_test.go b/types/errors_test.go
index 52de6e14f6a5..0a6df2d3c2c2 100644
--- a/types/errors_test.go
+++ b/types/errors_test.go
@@ -5,6 +5,8 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/require"
+
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 )
 
 var codeTypes = []CodeType{
@@ -93,3 +95,43 @@ func TestAppendMsgToErr(t *testing.T) {
 			fmt.Sprintf("Should have formatted the error message of ABCI Log. tc #%d", i))
 	}
 }
+
+func TestResultFromError(t *testing.T) {
+	cases := map[string]struct {
+		err    error
+		expect Result
+	}{
+		"sdk.Error": {
+			err: ErrUnauthorized("not owner"),
+			expect: Result{
+				Codespace: CodespaceRoot,
+				Code:      CodeUnauthorized,
+				Log:       `{"codespace":"sdk","code":4,"message":"not owner"}`,
+			},
+		},
+		"types/errors": {
+			err: sdkerrors.Wrap(sdkerrors.ErrUnauthorized, "not owner"),
+			expect: Result{
+				Codespace: CodespaceRoot,
+				Code:      CodeUnauthorized,
+				Log:       `{"codespace":"sdk","code":4,"message":"not owner: unauthorized"}`,
+			},
+		},
+		"stdlib errors": {
+			err: fmt.Errorf("not owner"),
+			expect: Result{
+				Codespace: CodespaceType("undefined"),
+				Code:      CodeInternal,
+				// note that we redact the internal errors in the new package to not leak eg. panics
+				Log: `{"codespace":"undefined","code":1,"message":"internal error"}`,
+			},
+		},
+	}
+
+	for name, tc := range cases {
+		t.Run(name, func(t *testing.T) {
+			res := ResultFromError(tc.err)
+			require.Equal(t, tc.expect, res)
+		})
+	}
+}