GODRIVER-2603 (Contd.) Revised error handling using Go 1.13 error APIs (

#1488)

bson/bsoncodec/default_value_encoders_test.go

@@ -1776,7 +1776,7 @@ func TestDefaultValueEncoders(t *testing.T) {
 				enc, err := reg.LookupEncoder(reflect.TypeOf(tc.value))
 				noerr(t, err)
 				err = enc.EncodeValue(EncodeContext{Registry: reg}, vw, reflect.ValueOf(tc.value))
-				if err != tc.err {
+				if !errors.Is(err, tc.err) {
 					t.Errorf("Did not receive expected error. got %v; want %v", err, tc.err)
 				}
 				if diff := cmp.Diff([]byte(b), tc.b); diff != "" {

bson/bsoncodec/map_codec.go

@@ -129,7 +129,7 @@ func (mc *MapCodec) mapEncodeValue(ec EncodeContext, dw bsonrw.DocumentWriter, v
 		}
 
 		currEncoder, currVal, lookupErr := defaultValueEncoders.lookupElementEncoder(ec, encoder, val.MapIndex(key))
-		if lookupErr != nil && lookupErr != errInvalidValue {
+		if lookupErr != nil && !errors.Is(lookupErr, errInvalidValue) {
 			return lookupErr
 		}
 

bson/bsoncodec/registry_test.go

@@ -352,8 +352,7 @@ func TestRegistryBuilder(t *testing.T) {
 					})
 					t.Run("Decoder", func(t *testing.T) {
 						wanterr := tc.wanterr
-						var ene ErrNoEncoder
-						if errors.As(tc.wanterr, &ene) {
+						if ene, ok := tc.wanterr.(ErrNoEncoder); ok {
 							wanterr = ErrNoDecoder(ene)
 						}
 
@@ -424,7 +423,7 @@ func TestRegistryBuilder(t *testing.T) {
 		want = nil
 		wanterr := ErrNoTypeMapEntry{Type: bsontype.ObjectID}
 		got, err = reg.LookupTypeMapEntry(bsontype.ObjectID)
-		if err != wanterr {
+		if !errors.Is(err, wanterr) {
 			t.Errorf("did not get expected error: got %#v, want %#v", err, wanterr)
 		}
 		if got != want {
@@ -777,8 +776,7 @@ func TestRegistry(t *testing.T) {
 						t.Parallel()
 
 						wanterr := tc.wanterr
-						var ene ErrNoEncoder
-						if errors.As(tc.wanterr, &ene) {
+						if ene, ok := tc.wanterr.(ErrNoEncoder); ok {
 							wanterr = ErrNoDecoder(ene)
 						}
 
@@ -884,7 +882,7 @@ func TestRegistry(t *testing.T) {
 		want = nil
 		wanterr := ErrNoTypeMapEntry{Type: bsontype.ObjectID}
 		got, err = reg.LookupTypeMapEntry(bsontype.ObjectID)
-		if err != wanterr {
+		if !errors.Is(err, wanterr) {
 			t.Errorf("unexpected error: got %#v, want %#v", err, wanterr)
 		}
 		if got != want {

bson/bsoncodec/slice_codec.go

@@ -7,6 +7,7 @@
 package bsoncodec
 
 import (
+	"errors"
 	"fmt"
 	"reflect"
 
@@ -93,7 +94,7 @@ func (sc SliceCodec) EncodeValue(ec EncodeContext, vw bsonrw.ValueWriter, val re
 
 	for idx := 0; idx < val.Len(); idx++ {
 		currEncoder, currVal, lookupErr := defaultValueEncoders.lookupElementEncoder(ec, encoder, val.Index(idx))
-		if lookupErr != nil && lookupErr != errInvalidValue {
+		if lookupErr != nil && !errors.Is(lookupErr, errInvalidValue) {
 			return lookupErr
 		}
 
@@ -102,7 +103,7 @@ func (sc SliceCodec) EncodeValue(ec EncodeContext, vw bsonrw.ValueWriter, val re
 			return err
 		}
 
-		if lookupErr == errInvalidValue {
+		if errors.Is(lookupErr, errInvalidValue) {
 			err = vw.WriteNull()
 			if err != nil {
 				return err

bson/bsoncodec/struct_codec.go

@@ -164,11 +164,11 @@ func (sc *StructCodec) EncodeValue(ec EncodeContext, vw bsonrw.ValueWriter, val
 
 		desc.encoder, rv, err = defaultValueEncoders.lookupElementEncoder(ec, desc.encoder, rv)
 
-		if err != nil && err != errInvalidValue {
+		if err != nil && !errors.Is(err, errInvalidValue) {
 			return err
 		}
 
-		if err == errInvalidValue {
+		if errors.Is(err, errInvalidValue) {
 			if desc.omitEmpty {
 				continue
 			}
@@ -308,7 +308,7 @@ func (sc *StructCodec) DecodeValue(dc DecodeContext, vr bsonrw.ValueReader, val
 
 	for {
 		name, vr, err := dr.ReadElement()
-		if err == bsonrw.ErrEOD {
+		if errors.Is(err, bsonrw.ErrEOD) {
 			break
 		}
 		if err != nil {

bson/bsonrw/extjson_reader_test.go

@@ -7,6 +7,7 @@
 package bsonrw
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"strings"
@@ -131,7 +132,7 @@ func readAllDocuments(vr ValueReader) ([][]byte, error) {
 		for {
 			result, err := c.CopyDocumentToBytes(vr)
 			if err != nil {
-				if err == io.EOF {
+				if errors.Is(err, io.EOF) {
 					break
 				}
 				return nil, err
@@ -147,7 +148,7 @@ func readAllDocuments(vr ValueReader) ([][]byte, error) {
 		for {
 			evr, err := ar.ReadValue()
 			if err != nil {
-				if err == ErrEOA {
+				if errors.Is(err, ErrEOA) {
 					break
 				}
 				return nil, err

bson/bsonrw/json_scanner.go

@@ -325,17 +325,17 @@ func (js *jsonScanner) scanLiteral(first byte) (*jsonToken, error) {
 
 	c5, err := js.readNextByte()
 
-	if bytes.Equal([]byte("true"), lit) && (isValueTerminator(c5) || err == io.EOF) {
+	if bytes.Equal([]byte("true"), lit) && (isValueTerminator(c5) || errors.Is(err, io.EOF)) {
 		js.pos = int(math.Max(0, float64(js.pos-1)))
 		return &jsonToken{t: jttBool, v: true, p: p}, nil
-	} else if bytes.Equal([]byte("null"), lit) && (isValueTerminator(c5) || err == io.EOF) {
+	} else if bytes.Equal([]byte("null"), lit) && (isValueTerminator(c5) || errors.Is(err, io.EOF)) {
 		js.pos = int(math.Max(0, float64(js.pos-1)))
 		return &jsonToken{t: jttNull, v: nil, p: p}, nil
 	} else if bytes.Equal([]byte("fals"), lit) {
 		if c5 == 'e' {
 			c5, err = js.readNextByte()
 
-			if isValueTerminator(c5) || err == io.EOF {
+			if isValueTerminator(c5) || errors.Is(err, io.EOF) {
 				js.pos = int(math.Max(0, float64(js.pos-1)))
 				return &jsonToken{t: jttBool, v: false, p: p}, nil
 			}
@@ -413,7 +413,7 @@ func (js *jsonScanner) scanNumber(first byte) (*jsonToken, error) {
 			case '}', ']', ',':
 				s = nssDone
 			default:
-				if isWhiteSpace(c) || err == io.EOF {
+				if isWhiteSpace(c) || errors.Is(err, io.EOF) {
 					s = nssDone
 				} else {
 					s = nssInvalid
@@ -430,7 +430,7 @@ func (js *jsonScanner) scanNumber(first byte) (*jsonToken, error) {
 			case '}', ']', ',':
 				s = nssDone
 			default:
-				if isWhiteSpace(c) || err == io.EOF {
+				if isWhiteSpace(c) || errors.Is(err, io.EOF) {
 					s = nssDone
 				} else if isDigit(c) {
 					s = nssSawIntegerDigits
@@ -455,7 +455,7 @@ func (js *jsonScanner) scanNumber(first byte) (*jsonToken, error) {
 			case '}', ']', ',':
 				s = nssDone
 			default:
-				if isWhiteSpace(c) || err == io.EOF {
+				if isWhiteSpace(c) || errors.Is(err, io.EOF) {
 					s = nssDone
 				} else if isDigit(c) {
 					s = nssSawFractionDigits
@@ -490,7 +490,7 @@ func (js *jsonScanner) scanNumber(first byte) (*jsonToken, error) {
 			case '}', ']', ',':
 				s = nssDone
 			default:
-				if isWhiteSpace(c) || err == io.EOF {
+				if isWhiteSpace(c) || errors.Is(err, io.EOF) {
 					s = nssDone
 				} else if isDigit(c) {
 					s = nssSawExponentDigits

bson/bsonrw/value_reader_test.go

@@ -1527,7 +1527,7 @@ func errequal(t *testing.T, err1, err2 error) bool {
 		return false
 	}
 
-	if err1 == err2 { // They are the same error, they are equal
+	if errors.Is(err1, err2) { // They are the same error, they are equal
 		return true
 	}
 

bson/raw_test.go

@@ -118,7 +118,7 @@ func TestRaw(t *testing.T) {
 		for _, tc := range testCases {
 			t.Run(tc.name, func(t *testing.T) {
 				err := tc.r.Validate()
-				if err != tc.err {
+				if !errors.Is(err, tc.err) {
 					t.Errorf("Returned error does not match. got %v; want %v", err, tc.err)
 				}
 			})
@@ -128,7 +128,7 @@ func TestRaw(t *testing.T) {
 		t.Run("empty-key", func(t *testing.T) {
 			rdr := Raw{'\x05', '\x00', '\x00', '\x00', '\x00'}
 			_, err := rdr.LookupErr()
-			if err != bsoncore.ErrEmptyKey {
+			if !errors.Is(err, bsoncore.ErrEmptyKey) {
 				t.Errorf("Empty key lookup did not return expected result. got %v; want %v", err, bsoncore.ErrEmptyKey)
 			}
 		})
@@ -211,7 +211,7 @@ func TestRaw(t *testing.T) {
 		for _, tc := range testCases {
 			t.Run(tc.name, func(t *testing.T) {
 				got, err := tc.r.LookupErr(tc.key...)
-				if err != tc.err {
+				if !errors.Is(err, tc.err) {
 					t.Errorf("Returned error does not match. got %v; want %v", err, tc.err)
 				}
 				if !cmp.Equal(got, tc.want) {
@@ -224,7 +224,7 @@ func TestRaw(t *testing.T) {
 		t.Run("Out of bounds", func(t *testing.T) {
 			rdr := Raw{0xe, 0x0, 0x0, 0x0, 0xa, 0x78, 0x0, 0xa, 0x79, 0x0, 0xa, 0x7a, 0x0, 0x0}
 			_, err := rdr.IndexErr(3)
-			if err != bsoncore.ErrOutOfBounds {
+			if !errors.Is(err, bsoncore.ErrOutOfBounds) {
 				t.Errorf("Out of bounds should be returned when accessing element beyond end of document. got %v; want %v", err, bsoncore.ErrOutOfBounds)
 			}
 		})

bson/raw_value_test.go

@@ -7,6 +7,7 @@
 package bson
 
 import (
+	"errors"
 	"fmt"
 	"reflect"
 	"testing"
@@ -57,7 +58,7 @@ func TestRawValue(t *testing.T) {
 			want := ErrNilRegistry
 			var val RawValue
 			got := val.UnmarshalWithRegistry(nil, &D{})
-			if got != want {
+			if !errors.Is(got, want) {
 				t.Errorf("Expected errors to match. got %v; want %v", got, want)
 			}
 		})
@@ -108,7 +109,7 @@ func TestRawValue(t *testing.T) {
 			want := ErrNilContext
 			var val RawValue
 			got := val.UnmarshalWithContext(nil, &D{})
-			if got != want {
+			if !errors.Is(got, want) {
 				t.Errorf("Expected errors to match. got %v; want %v", got, want)
 			}
 		})

bson/unmarshal_test.go

@@ -7,6 +7,7 @@
 package bson
 
 import (
+	"errors"
 	"math/rand"
 	"reflect"
 	"sync"
@@ -100,7 +101,7 @@ func TestUnmarshalExtJSONWithRegistry(t *testing.T) {
 	t.Run("UnmarshalExtJSONInvalidInput", func(t *testing.T) {
 		data := []byte("invalid")
 		err := UnmarshalExtJSONWithRegistry(DefaultRegistry, data, true, &M{})
-		if err != bsonrw.ErrInvalidJSON {
+		if !errors.Is(err, bsonrw.ErrInvalidJSON) {
 			t.Fatalf("wanted ErrInvalidJSON, got %v", err)
 		}
 	})

examples/documentation_examples/examples.go

@@ -8,7 +8,6 @@ package documentation_examples
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"io/ioutil"
 	logger "log"
@@ -1817,8 +1816,7 @@ func RunTransactionWithRetry(sctx mongo.SessionContext, txnFn func(mongo.Session
 		log.Println("Transaction aborted. Caught exception during transaction.")
 
 		// If transient error, retry the whole transaction
-		var cmdErr mongo.CommandError
-		if errors.As(err, &cmdErr) && cmdErr.HasErrorLabel("TransientTransactionError") {
+		if cmdErr, ok := err.(mongo.CommandError); ok && cmdErr.HasErrorLabel("TransientTransactionError") {
 			log.Println("TransientTransactionError, retrying transaction...")
 			continue
 		}
@@ -1885,8 +1883,7 @@ func TransactionsExamples(ctx context.Context, client *mongo.Client) error {
 			log.Println("Transaction aborted. Caught exception during transaction.")
 
 			// If transient error, retry the whole transaction
-			var cmdErr mongo.CommandError
-			if errors.As(err, &cmdErr) && cmdErr.HasErrorLabel("TransientTransactionError") {
+			if cmdErr, ok := err.(mongo.CommandError); ok && cmdErr.HasErrorLabel("TransientTransactionError") {
 				log.Println("TransientTransactionError, retrying transaction...")
 				continue
 			}

internal/aws/awserr/types.go

@@ -11,7 +11,6 @@
 package awserr
 
 import (
-	"errors"
 	"fmt"
 )
 
@@ -107,8 +106,7 @@ func (b baseError) OrigErr() error {
 	case 1:
 		return b.errs[0]
 	default:
-		var err Error
-		if errors.As(b.errs[0], &err) {
+		if err, ok := b.errs[0].(Error); ok {
 			return NewBatchError(err.Code(), err.Message(), b.errs[1:])
 		}
 		return NewBatchError("BatchedErrors",

mongo/bulk_write.go

@@ -72,7 +72,7 @@ func (bw *bulkWrite) execute(ctx context.Context) error {
 
 		bwErr.WriteErrors = append(bwErr.WriteErrors, batchErr.WriteErrors...)
 
-		commandErrorOccurred := err != nil && err != driver.ErrUnacknowledgedWrite
+		commandErrorOccurred := err != nil && !errors.Is(err, driver.ErrUnacknowledgedWrite)
 		writeErrorOccurred := len(batchErr.WriteErrors) > 0 || batchErr.WriteConcernError != nil
 		if !continueOnError && (commandErrorOccurred || writeErrorOccurred) {
 			if err != nil {

mongo/crud_examples_test.go

@@ -8,6 +8,7 @@ package mongo_test
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"log"
 	"sync"
@@ -387,7 +388,7 @@ func ExampleCollection_FindOne() {
 	if err != nil {
 		// ErrNoDocuments means that the filter did not match any documents in
 		// the collection.
-		if err == mongo.ErrNoDocuments {
+		if errors.Is(err, mongo.ErrNoDocuments) {
 			return
 		}
 		log.Fatal(err)
@@ -413,7 +414,7 @@ func ExampleCollection_FindOneAndDelete() {
 	if err != nil {
 		// ErrNoDocuments means that the filter did not match any documents in
 		// the collection.
-		if err == mongo.ErrNoDocuments {
+		if errors.Is(err, mongo.ErrNoDocuments) {
 			return
 		}
 		log.Fatal(err)
@@ -442,7 +443,7 @@ func ExampleCollection_FindOneAndReplace() {
 	if err != nil {
 		// ErrNoDocuments means that the filter did not match any documents in
 		// the collection.
-		if err == mongo.ErrNoDocuments {
+		if errors.Is(err, mongo.ErrNoDocuments) {
 			return
 		}
 		log.Fatal(err)
@@ -471,7 +472,7 @@ func ExampleCollection_FindOneAndUpdate() {
 	if err != nil {
 		// ErrNoDocuments means that the filter did not match any documents in
 		// the collection.
-		if err == mongo.ErrNoDocuments {
+		if errors.Is(err, mongo.ErrNoDocuments) {
 			return
 		}
 		log.Fatal(err)