Avoid panics when Unwrap/Cause return nil errors

Co-authored-by: Marcelo Vanzin <marcelo.vanzin@includedhealth.com>

encoder_test.go

@@ -272,11 +272,12 @@ func TestEncodeEntry(t *testing.T) {
 			//          .cause.0.cause.0=joined 1
 			//                  .cause.1=joined 2
 			//          .cause.1=fmt error
+			//  ↳ nil_cause_error=Error has nil cause
 			//  ↳ stacktrace=github.com/thessem/zap-prettyconsole.TestEncodeEntry
 			//                       /<some_file>:<line_number>
 			//               testing.tRunner
 			//                       /<some_file>:<line_number>
-			expected: "\x1b[90m4:33PM\x1b[0m\x1b[31m \x1b[0m\x1b[31mERR\x1b[0m\x1b[31m \x1b[0m\x1b[1m\x1b[31m>\x1b[0m\x1b[0m\x1b[31m \x1b[0mtest message\n\x1b[31m  ↳ error\x1b[0m\x1b[31m=\x1b[0merror with context\n          \x1b[31m.cause\x1b[0m\x1b[31m=\x1b[0mcause 1\n\x1b[31m  ↳ error\x1b[0m\x1b[31m=\x1b[0merrors with context\n          \x1b[31m.cause.0\x1b[0m\x1b[31m=\x1b[0mcause 1\n          \x1b[31m.cause.1\x1b[0m\x1b[31m=\x1b[0mcause 2\n\x1b[31m  ↳ error\x1b[0m\x1b[31m.cause.0\x1b[0m\x1b[31m=\x1b[0mjoined cause 1\n         \x1b[31m.cause.1\x1b[0m\x1b[31m=\x1b[0mjoined cause 2\n\x1b[31m  ↳ error\x1b[0m\x1b[31m=\x1b[0mJoined and fmt\n          \x1b[31m.cause.0\x1b[0m\x1b[31m.cause.0\x1b[0m\x1b[31m=\x1b[0mjoined 1\n                  \x1b[31m.cause.1\x1b[0m\x1b[31m=\x1b[0mjoined 2\n          \x1b[31m.cause.1\x1b[0m\x1b[31m=\x1b[0mfmt error\n\x1b[31m  ↳ \x1b[0m\x1b[31mstacktrace=\x1b[0mgithub.com/thessem/zap-prettyconsole.TestEncodeEntry\n               \t/<some_file>:<line_number>\n               testing.tRunner\n               \t/<some_file>:<line_number>\n",
+			expected: "\x1b[90m4:33PM\x1b[0m\x1b[31m \x1b[0m\x1b[31mERR\x1b[0m\x1b[31m \x1b[0m\x1b[1m\x1b[31m>\x1b[0m\x1b[0m\x1b[31m \x1b[0mtest message\n\x1b[31m  ↳ error\x1b[0m\x1b[31m=\x1b[0merror with context\n          \x1b[31m.cause\x1b[0m\x1b[31m=\x1b[0mcause 1\n\x1b[31m  ↳ error\x1b[0m\x1b[31m=\x1b[0merrors with context\n          \x1b[31m.cause.0\x1b[0m\x1b[31m=\x1b[0mcause 1\n          \x1b[31m.cause.1\x1b[0m\x1b[31m=\x1b[0mcause 2\n\x1b[31m  ↳ error\x1b[0m\x1b[31m.cause.0\x1b[0m\x1b[31m=\x1b[0mjoined cause 1\n         \x1b[31m.cause.1\x1b[0m\x1b[31m=\x1b[0mjoined cause 2\n\x1b[31m  ↳ error\x1b[0m\x1b[31m=\x1b[0mJoined and fmt\n          \x1b[31m.cause.0\x1b[0m\x1b[31m.cause.0\x1b[0m\x1b[31m=\x1b[0mjoined 1\n                  \x1b[31m.cause.1\x1b[0m\x1b[31m=\x1b[0mjoined 2\n          \x1b[31m.cause.1\x1b[0m\x1b[31m=\x1b[0mfmt error\n\x1b[31m  ↳ nil_cause_error\x1b[0m\x1b[31m=\x1b[0mError has nil cause\n\x1b[31m  ↳ \x1b[0m\x1b[31mstacktrace=\x1b[0mgithub.com/thessem/zap-prettyconsole.TestEncodeEntry\n               \t/<some_file>:<line_number>\n               testing.tRunner\n               \t/<some_file>:<line_number>\n",
 			ent: zapcore.Entry{
 				Level:   zapcore.ErrorLevel,
 				Message: "test message",
@@ -289,6 +290,8 @@ func TestEncodeEntry(t *testing.T) {
 				zap.Error(fmt.Errorf("errors with context: %w, %w", errors.New("cause 1"), errors.New("cause 2"))),
 				zap.Error(errors.Join(errors.New("joined cause 1"), errors.New("joined cause 2"))),
 				zap.Error(fmt.Errorf("Joined and fmt: %w and %w", errors.Join(fmt.Errorf("joined 1"), fmt.Errorf("joined 2")), fmt.Errorf("fmt error"))),
+				zap.NamedError("nil_cause_error", nilCauseError{}),
+				zap.NamedError("nill_error", nil),
 			},
 		},
 	}
@@ -345,6 +348,16 @@ func (t *testPanicError) Error() string {
 	}
 }
 
+type nilCauseError struct{}
+
+func (nilCauseError) Error() string {
+	return "Error has nil cause"
+}
+
+func (nilCauseError) Cause() error {
+	return nil
+}
+
 type testArray []interface{}
 
 func (t testArray) MarshalLogArray(encoder zapcore.ArrayEncoder) error {

error.go

@@ -86,6 +86,9 @@ func (e *prettyConsoleEncoder) encodeError(key string, err error) (retErr error)
 	// Write causes recursively
 	skipDetail := false
 	for i, ei := range causes {
+		if ei == nil {
+			continue
+		}
 		if len(causes) > 1 {
 			key = "cause." + strconv.Itoa(i)
 		} else {

go.sum

@@ -1,20 +1,12 @@
 github.com/Code-Hex/dd v1.1.0 h1:VEtTThnS9l7WhpKUIpdcWaf0B8Vp0LeeSEsxA1DZseI=
 github.com/Code-Hex/dd v1.1.0/go.mod h1:VaMyo/YjTJ3d4qm/bgtrUkT2w+aYwJ07Y7eCWyrJr1w=
-github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/google/go-cmp v0.5.7 h1:81/ik6ipDQS2aGcBfIN5dHDB36BwrStyeAQquSYCV4o=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
-github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
-github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
-github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
-github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
 github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
@@ -24,6 +16,5 @@ go.uber.org/zap v1.27.0 h1:aJMhYGrd5QSmlpLMr2MftRKl7t8J8PTZPA732ud/XR8=
 go.uber.org/zap v1.27.0/go.mod h1:GB2qFLM7cTU87MWRP2mPIjqfIDnGu+VIO4V/SdhGo2E=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=