all: make use of stringslite.{HasPrefix, HasSuffix}

Just a code cleanup.

Change-Id: Ie887ab2c71de11b4844c4e6fd4e5aca3265ac3aa
Reviewed-on: https://go-review.googlesource.com/c/go/+/583216
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>

4 files changed, 12 insertions, 20 deletions

diff --git a/src/net/conf.go b/src/net/conf.go
index 20c81b95de..7499d49045 100644
--- a/src/net/conf.go
+++ b/src/net/conf.go
@@ -8,6 +8,7 @@ import (
 	"errors"
 	"internal/bytealg"
 	"internal/godebug"
+	"internal/stringslite"
 	"io/fs"
 	"os"
 	"runtime"
@@ -335,7 +336,7 @@ func (c *conf) lookupOrder(r *Resolver, hostname string) (ret hostLookupOrder, d
 	}
 
 	// Canonicalize the hostname by removing any trailing dot.
-	if stringsHasSuffix(hostname, ".") {
+	if stringslite.HasSuffix(hostname, ".") {
 		hostname = hostname[:len(hostname)-1]
 	}
 
@@ -396,7 +397,7 @@ func (c *conf) lookupOrder(r *Resolver, hostname string) (ret hostLookupOrder, d
 					return hostLookupCgo, dnsConf
 				}
 				continue
-			case hostname != "" && stringsHasPrefix(src.source, "mdns"):
+			case hostname != "" && stringslite.HasPrefix(src.source, "mdns"):
 				if stringsHasSuffixFold(hostname, ".local") {
 					// Per RFC 6762, the ".local" TLD is special. And
 					// because Go's native resolver doesn't do mDNS or
diff --git a/src/net/interface_plan9.go b/src/net/interface_plan9.go
index 92b2eed259..7c44566acf 100644
--- a/src/net/interface_plan9.go
+++ b/src/net/interface_plan9.go
@@ -7,6 +7,7 @@ package net
 import (
 	"errors"
 	"internal/itoa"
+	"internal/stringslite"
 	"os"
 )
 
@@ -70,7 +71,7 @@ func readInterface(i int) (*Interface, error) {
 	ifc.MTU = mtu
 
 	// Not a loopback device ("/dev/null") or packet interface (e.g. "pkt2")
-	if stringsHasPrefix(device, netdir+"/") {
+	if stringslite.HasPrefix(device, netdir+"/") {
 		deviceaddrf, err := open(device + "/addr")
 		if err != nil {
 			return nil, err
diff --git a/src/net/lookup_plan9.go b/src/net/lookup_plan9.go
index 588174b1fc..5c869374f6 100644
--- a/src/net/lookup_plan9.go
+++ b/src/net/lookup_plan9.go
@@ -9,6 +9,7 @@ import (
 	"errors"
 	"internal/bytealg"
 	"internal/itoa"
+	"internal/stringslite"
 	"io"
 	"os"
 )
@@ -107,10 +108,10 @@ func queryDNS(ctx context.Context, addr string, typ string) (res []string, err e
 }
 
 func handlePlan9DNSError(err error, name string) error {
-	if stringsHasSuffix(err.Error(), "dns: name does not exist") ||
-		stringsHasSuffix(err.Error(), "dns: resource does not exist; negrcode 0") ||
-		stringsHasSuffix(err.Error(), "dns: resource does not exist; negrcode") ||
-		stringsHasSuffix(err.Error(), "dns failure") {
+	if stringslite.HasSuffix(err.Error(), "dns: name does not exist") ||
+		stringslite.HasSuffix(err.Error(), "dns: resource does not exist; negrcode 0") ||
+		stringslite.HasSuffix(err.Error(), "dns: resource does not exist; negrcode") ||
+		stringslite.HasSuffix(err.Error(), "dns failure") {
 		err = errNoSuchHost
 	}
 	return newDNSError(err, name, "")
@@ -227,7 +228,7 @@ func (r *Resolver) lookupPort(ctx context.Context, network, service string) (por
 func (*Resolver) lookupPortWithNetwork(ctx context.Context, network, errNetwork, service string) (port int, err error) {
 	lines, err := queryCS(ctx, network, "127.0.0.1", toLower(service))
 	if err != nil {
-		if stringsHasSuffix(err.Error(), "can't translate service") {
+		if stringslite.HasSuffix(err.Error(), "can't translate service") {
 			return 0, &DNSError{Err: "unknown port", Name: errNetwork + "/" + service, IsNotFound: true}
 		}
 		return
@@ -256,7 +257,7 @@ func (r *Resolver) lookupCNAME(ctx context.Context, name string) (cname string,
 
 	lines, err := queryDNS(ctx, name, "cname")
 	if err != nil {
-		if stringsHasSuffix(err.Error(), "dns failure") || stringsHasSuffix(err.Error(), "resource does not exist; negrcode 0") {
+		if stringslite.HasSuffix(err.Error(), "dns failure") || stringslite.HasSuffix(err.Error(), "resource does not exist; negrcode 0") {
 			return absDomainName(name), nil
 		}
 		return "", handlePlan9DNSError(err, cname)
diff --git a/src/net/parse.go b/src/net/parse.go
index 29dffad43c..106a303dfa 100644
--- a/src/net/parse.go
+++ b/src/net/parse.go
@@ -251,23 +251,12 @@ func foreachField(x string, fn func(field string) error) error {
 	return nil
 }
 
-// stringsHasSuffix is strings.HasSuffix. It reports whether s ends in
-// suffix.
-func stringsHasSuffix(s, suffix string) bool {
-	return len(s) >= len(suffix) && s[len(s)-len(suffix):] == suffix
-}
-
 // stringsHasSuffixFold reports whether s ends in suffix,
 // ASCII-case-insensitively.
 func stringsHasSuffixFold(s, suffix string) bool {
 	return len(s) >= len(suffix) && stringsEqualFold(s[len(s)-len(suffix):], suffix)
 }
 
-// stringsHasPrefix is strings.HasPrefix. It reports whether s begins with prefix.
-func stringsHasPrefix(s, prefix string) bool {
-	return len(s) >= len(prefix) && s[:len(prefix)] == prefix
-}
-
 // stringsEqualFold is strings.EqualFold, ASCII only. It reports whether s and t
 // are equal, ASCII-case-insensitively.
 func stringsEqualFold(s, t string) bool {