src: rename unexported errors by adding prefix err

By convention, use `err` as prefix for variables of type `error`.

Change-Id: I9401d5d47e994a27be245b2c8b1edd55cdd52db1
Reviewed-on: https://go-review.googlesource.com/c/go/+/467536
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>

6 files changed, 36 insertions, 36 deletions

diff --git a/src/encoding/binary/varint.go b/src/encoding/binary/varint.go
index 18e1ff1511..7b14fb2b63 100644
--- a/src/encoding/binary/varint.go
+++ b/src/encoding/binary/varint.go
@@ -123,7 +123,7 @@ func Varint(buf []byte) (int64, int) {
 	return x, n
 }
 
-var overflow = errors.New("binary: varint overflows a 64-bit integer")
+var errOverflow = errors.New("binary: varint overflows a 64-bit integer")
 
 // ReadUvarint reads an encoded unsigned integer from r and returns it as a uint64.
 // The error is EOF only if no bytes were read.
@@ -142,14 +142,14 @@ func ReadUvarint(r io.ByteReader) (uint64, error) {
 		}
 		if b < 0x80 {
 			if i == MaxVarintLen64-1 && b > 1 {
-				return x, overflow
+				return x, errOverflow
 			}
 			return x | uint64(b)<<s, nil
 		}
 		x |= uint64(b&0x7f) << s
 		s += 7
 	}
-	return x, overflow
+	return x, errOverflow
 }
 
 // ReadVarint reads an encoded signed integer from r and returns it as an int64.
diff --git a/src/encoding/binary/varint_test.go b/src/encoding/binary/varint_test.go
index a3caea8a43..5c3ea318c3 100644
--- a/src/encoding/binary/varint_test.go
+++ b/src/encoding/binary/varint_test.go
@@ -212,9 +212,9 @@ func testOverflow(t *testing.T, buf []byte, x0 uint64, n0 int, err0 error) {
 }
 
 func TestOverflow(t *testing.T) {
-	testOverflow(t, []byte{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x2}, 0, -10, overflow)
-	testOverflow(t, []byte{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x1, 0, 0}, 0, -11, overflow)
-	testOverflow(t, []byte{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}, 1<<64-1, -11, overflow) // 11 bytes, should overflow
+	testOverflow(t, []byte{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x2}, 0, -10, errOverflow)
+	testOverflow(t, []byte{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x1, 0, 0}, 0, -11, errOverflow)
+	testOverflow(t, []byte{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}, 1<<64-1, -11, errOverflow) // 11 bytes, should overflow
 }
 
 func TestNonCanonicalZero(t *testing.T) {
diff --git a/src/fmt/scan.go b/src/fmt/scan.go
index 2780b82de2..5dd0971642 100644
--- a/src/fmt/scan.go
+++ b/src/fmt/scan.go
@@ -462,8 +462,8 @@ func (s *ss) token(skipSpace bool, f func(rune) bool) []byte {
 	return s.buf
 }
 
-var complexError = errors.New("syntax error scanning complex number")
-var boolError = errors.New("syntax error scanning boolean")
+var errComplex = errors.New("syntax error scanning complex number")
+var errBool = errors.New("syntax error scanning boolean")
 
 func indexRune(s string, r rune) int {
 	for i, c := range s {
@@ -542,12 +542,12 @@ func (s *ss) scanBool(verb rune) bool {
 		return true
 	case 't', 'T':
 		if s.accept("rR") && (!s.accept("uU") || !s.accept("eE")) {
-			s.error(boolError)
+			s.error(errBool)
 		}
 		return true
 	case 'f', 'F':
 		if s.accept("aA") && (!s.accept("lL") || !s.accept("sS") || !s.accept("eE")) {
-			s.error(boolError)
+			s.error(errBool)
 		}
 		return false
 	}
@@ -747,16 +747,16 @@ func (s *ss) complexTokens() (real, imag string) {
 	s.buf = s.buf[:0]
 	// Must now have a sign.
 	if !s.accept("+-") {
-		s.error(complexError)
+		s.error(errComplex)
 	}
 	// Sign is now in buffer
 	imagSign := string(s.buf)
 	imag = s.floatToken()
 	if !s.accept("i") {
-		s.error(complexError)
+		s.error(errComplex)
 	}
 	if parens && !s.accept(")") {
-		s.error(complexError)
+		s.error(errComplex)
 	}
 	return real, imagSign + imag
 }
diff --git a/src/time/format.go b/src/time/format.go
index f94d68ee02..7fbeddb540 100644
--- a/src/time/format.go
+++ b/src/time/format.go
@@ -446,7 +446,7 @@ func appendInt(b []byte, x int, width int) []byte {
 }
 
 // Never printed, just needs to be non-nil for return by atoi.
-var atoiError = errors.New("time: invalid number")
+var errAtoi = errors.New("time: invalid number")
 
 // Duplicates functionality in strconv, but avoids dependency.
 func atoi[bytes []byte | string](s bytes) (x int, err error) {
@@ -458,7 +458,7 @@ func atoi[bytes []byte | string](s bytes) (x int, err error) {
 	q, rem, err := leadingInt(s)
 	x = int(q)
 	if err != nil || len(rem) > 0 {
-		return 0, atoiError
+		return 0, errAtoi
 	}
 	if neg {
 		x = -x
diff --git a/src/time/zoneinfo_plan9.go b/src/time/zoneinfo_plan9.go
index 5d432fe297..d13b623a37 100644
--- a/src/time/zoneinfo_plan9.go
+++ b/src/time/zoneinfo_plan9.go
@@ -56,7 +56,7 @@ func loadZoneDataPlan9(s string) (l *Location, err error) {
 		if len(f) == 2 && f[0] == "GMT" {
 			return UTC, nil
 		}
-		return nil, badData
+		return nil, errBadData
 	}
 
 	var zones [2]zone
@@ -64,14 +64,14 @@ func loadZoneDataPlan9(s string) (l *Location, err error) {
 	// standard timezone offset
 	o, err := atoi(f[1])
 	if err != nil {
-		return nil, badData
+		return nil, errBadData
 	}
 	zones[0] = zone{name: f[0], offset: o, isDST: false}
 
 	// alternate timezone offset
 	o, err = atoi(f[3])
 	if err != nil {
-		return nil, badData
+		return nil, errBadData
 	}
 	zones[1] = zone{name: f[2], offset: o, isDST: true}
 
@@ -85,7 +85,7 @@ func loadZoneDataPlan9(s string) (l *Location, err error) {
 		}
 		t, err := atoi(f[i])
 		if err != nil {
-			return nil, badData
+			return nil, errBadData
 		}
 		t -= zones[0].offset
 		tx = append(tx, zoneTrans{when: int64(t), index: uint8(zi)})
diff --git a/src/time/zoneinfo_read.go b/src/time/zoneinfo_read.go
index 90814ad36a..d8b35003a1 100644
--- a/src/time/zoneinfo_read.go
+++ b/src/time/zoneinfo_read.go
@@ -107,7 +107,7 @@ func byteString(p []byte) string {
 	return string(p)
 }
 
-var badData = errors.New("malformed time zone information")
+var errBadData = errors.New("malformed time zone information")
 
 // LoadLocationFromTZData returns a Location with the given name
 // initialized from the IANA Time Zone database-formatted data.
@@ -118,14 +118,14 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) {
 
 	// 4-byte magic "TZif"
 	if magic := d.read(4); string(magic) != "TZif" {
-		return nil, badData
+		return nil, errBadData
 	}
 
 	// 1-byte version, then 15 bytes of padding
 	var version int
 	var p []byte
 	if p = d.read(16); len(p) != 16 {
-		return nil, badData
+		return nil, errBadData
 	} else {
 		switch p[0] {
 		case 0:
@@ -135,7 +135,7 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) {
 		case '3':
 			version = 3
 		default:
-			return nil, badData
+			return nil, errBadData
 		}
 	}
 
@@ -158,10 +158,10 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) {
 	for i := 0; i < 6; i++ {
 		nn, ok := d.big4()
 		if !ok {
-			return nil, badData
+			return nil, errBadData
 		}
 		if uint32(int(nn)) != nn {
-			return nil, badData
+			return nil, errBadData
 		}
 		n[i] = int(nn)
 	}
@@ -191,10 +191,10 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) {
 		for i := 0; i < 6; i++ {
 			nn, ok := d.big4()
 			if !ok {
-				return nil, badData
+				return nil, errBadData
 			}
 			if uint32(int(nn)) != nn {
-				return nil, badData
+				return nil, errBadData
 			}
 			n[i] = int(nn)
 		}
@@ -229,7 +229,7 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) {
 	isutc := d.read(n[NUTCLocal])
 
 	if d.error { // ran out of data
-		return nil, badData
+		return nil, errBadData
 	}
 
 	var extend string
@@ -245,26 +245,26 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) {
 	if nzone == 0 {
 		// Reject tzdata files with no zones. There's nothing useful in them.
 		// This also avoids a panic later when we add and then use a fake transition (golang.org/issue/29437).
-		return nil, badData
+		return nil, errBadData
 	}
 	zones := make([]zone, nzone)
 	for i := range zones {
 		var ok bool
 		var n uint32
 		if n, ok = zonedata.big4(); !ok {
-			return nil, badData
+			return nil, errBadData
 		}
 		if uint32(int(n)) != n {
-			return nil, badData
+			return nil, errBadData
 		}
 		zones[i].offset = int(int32(n))
 		var b byte
 		if b, ok = zonedata.byte(); !ok {
-			return nil, badData
+			return nil, errBadData
 		}
 		zones[i].isDST = b != 0
 		if b, ok = zonedata.byte(); !ok || int(b) >= len(abbrev) {
-			return nil, badData
+			return nil, errBadData
 		}
 		zones[i].name = byteString(abbrev[b:])
 		if runtime.GOOS == "aix" && len(name) > 8 && (name[:8] == "Etc/GMT+" || name[:8] == "Etc/GMT-") {
@@ -283,20 +283,20 @@ func LoadLocationFromTZData(name string, data []byte) (*Location, error) {
 		var n int64
 		if !is64 {
 			if n4, ok := txtimes.big4(); !ok {
-				return nil, badData
+				return nil, errBadData
 			} else {
 				n = int64(int32(n4))
 			}
 		} else {
 			if n8, ok := txtimes.big8(); !ok {
-				return nil, badData
+				return nil, errBadData
 			} else {
 				n = int64(n8)
 			}
 		}
 		tx[i].when = n
 		if int(txzones[i]) >= len(zones) {
-			return nil, badData
+			return nil, errBadData
 		}
 		tx[i].index = txzones[i]
 		if i < len(isstd) {