golangci-lint: enable perfsprint linter

cli/compose/types/types.go:568:17: fmt.Sprintf can be replaced with faster strconv.FormatBool (perfsprint)
            return []byte(fmt.Sprintf("%v", e.External)), nil
                          ^
    cli/command/formatter/buildcache.go:174:9: fmt.Sprintf can be replaced with faster strconv.Itoa (perfsprint)
        return fmt.Sprintf("%d", c.v.UsageCount)
               ^
    cli/command/formatter/buildcache.go:178:9: fmt.Sprintf can be replaced with faster strconv.FormatBool (perfsprint)
        return fmt.Sprintf("%t", c.v.InUse)
               ^
    cli/command/formatter/buildcache.go:182:9: fmt.Sprintf can be replaced with faster strconv.FormatBool (perfsprint)
        return fmt.Sprintf("%t", c.v.Shared)
               ^
    cli/command/formatter/image.go:259:9: fmt.Sprintf can be replaced with faster strconv.FormatInt (perfsprint)
        return fmt.Sprintf("%d", c.i.Containers)
               ^
    cli/command/formatter/tabwriter/tabwriter_test.go:698:9: fmt.Sprintf can be replaced with faster strconv.Itoa (perfsprint)
            b.Run(fmt.Sprintf("%d", x), func(b *testing.B) {
                  ^
    cli/command/formatter/tabwriter/tabwriter_test.go:720:9: fmt.Sprintf can be replaced with faster strconv.Itoa (perfsprint)
            b.Run(fmt.Sprintf("%d", h), func(b *testing.B) {
                  ^
    cli/command/image/prune.go:62:31: fmt.Sprintf can be replaced with faster strconv.FormatBool (perfsprint)
        pruneFilters.Add("dangling", fmt.Sprintf("%v", !options.all))
                                     ^
    cli/command/network/formatter.go:92:9: fmt.Sprintf can be replaced with faster strconv.FormatBool (perfsprint)
        return fmt.Sprintf("%v", c.n.EnableIPv6)
               ^
    cli/command/network/formatter.go:96:9: fmt.Sprintf can be replaced with faster strconv.FormatBool (perfsprint)
        return fmt.Sprintf("%v", c.n.Internal)
               ^
    cli/command/service/formatter.go:745:9: fmt.Sprintf can be replaced with faster strconv.FormatUint (perfsprint)
            pub = fmt.Sprintf("%d", pr.pStart)
                  ^
    cli/command/service/formatter.go:750:9: fmt.Sprintf can be replaced with faster strconv.FormatUint (perfsprint)
            tgt = fmt.Sprintf("%d", pr.tStart)
                  ^
    cli/command/service/opts.go:49:10: fmt.Sprintf can be replaced with faster strconv.FormatUint (perfsprint)
            return fmt.Sprintf("%v", *i.value)
                   ^
    cli/compose/loader/loader.go:720:36: fmt.Sprint can be replaced with faster strconv.Itoa (perfsprint)
                    v, err := toServicePortConfigs(fmt.Sprint(value))
                                                   ^

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

.golangci.yml

@@ -16,6 +16,7 @@ linters:
     - misspell
     - nakedret
     - nilerr        # Detects code that returns nil even if it checks that the error is not nil.
+    - perfsprint    # Detects fmt.Sprintf uses that can be replaced with a faster alternative.
     - predeclared
     - revive
     - staticcheck

cli/command/formatter/buildcache.go

@@ -1,8 +1,8 @@
 package formatter
 
 import (
-	"fmt"
 	"sort"
+	"strconv"
 	"strings"
 	"time"
 
@@ -171,13 +171,13 @@ func (c *buildCacheContext) LastUsedSince() string {
 }
 
 func (c *buildCacheContext) UsageCount() string {
-	return fmt.Sprintf("%d", c.v.UsageCount)
+	return strconv.Itoa(c.v.UsageCount)
 }
 
 func (c *buildCacheContext) InUse() string {
-	return fmt.Sprintf("%t", c.v.InUse)
+	return strconv.FormatBool(c.v.InUse)
 }
 
 func (c *buildCacheContext) Shared() string {
-	return fmt.Sprintf("%t", c.v.Shared)
+	return strconv.FormatBool(c.v.Shared)
 }

cli/command/formatter/image.go

@@ -1,7 +1,7 @@
 package formatter
 
 import (
-	"fmt"
+	"strconv"
 	"time"
 
 	"github.com/distribution/reference"
@@ -256,7 +256,7 @@ func (c *imageContext) Containers() string {
 	if c.i.Containers == -1 {
 		return "N/A"
 	}
-	return fmt.Sprintf("%d", c.i.Containers)
+	return strconv.FormatInt(c.i.Containers, 10)
 }
 
 // VirtualSize shows the virtual size of the image and all of its parent

cli/command/formatter/tabwriter/tabwriter_test.go

@@ -8,6 +8,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"strconv"
 	"testing"
 )
 
@@ -695,7 +696,7 @@ func BenchmarkPyramid(b *testing.B) {
 	for _, x := range [...]int{10, 100, 1000} {
 		// Build a line with x cells.
 		line := bytes.Repeat([]byte("a\t"), x)
-		b.Run(fmt.Sprintf("%d", x), func(b *testing.B) {
+		b.Run(strconv.Itoa(x), func(b *testing.B) {
 			b.ReportAllocs()
 			for i := 0; i < b.N; i++ {
 				w := NewWriter(io.Discard, 4, 4, 1, ' ', 0) // no particular reason for these settings
@@ -717,7 +718,7 @@ func BenchmarkRagged(b *testing.B) {
 		lines[i] = bytes.Repeat([]byte("a\t"), w)
 	}
 	for _, h := range [...]int{10, 100, 1000} {
-		b.Run(fmt.Sprintf("%d", h), func(b *testing.B) {
+		b.Run(strconv.Itoa(h), func(b *testing.B) {
 			b.ReportAllocs()
 			for i := 0; i < b.N; i++ {
 				w := NewWriter(io.Discard, 4, 4, 1, ' ', 0) // no particular reason for these settings

cli/command/image/prune.go

@@ -3,6 +3,7 @@ package image
 import (
 	"context"
 	"fmt"
+	"strconv"
 	"strings"
 
 	"github.com/docker/cli/cli"
@@ -59,7 +60,7 @@ Are you sure you want to continue?`
 
 func runPrune(dockerCli command.Cli, options pruneOptions) (spaceReclaimed uint64, output string, err error) {
 	pruneFilters := options.filter.Value().Clone()
-	pruneFilters.Add("dangling", fmt.Sprintf("%v", !options.all))
+	pruneFilters.Add("dangling", strconv.FormatBool(!options.all))
 	pruneFilters = command.PruneFilters(dockerCli, pruneFilters)
 
 	warning := danglingWarning

cli/command/network/formatter.go

@@ -1,7 +1,7 @@
 package network
 
 import (
-	"fmt"
+	"strconv"
 	"strings"
 
 	"github.com/docker/cli/cli/command/formatter"
@@ -89,11 +89,11 @@ func (c *networkContext) Scope() string {
 }
 
 func (c *networkContext) IPv6() string {
-	return fmt.Sprintf("%v", c.n.EnableIPv6)
+	return strconv.FormatBool(c.n.EnableIPv6)
 }
 
 func (c *networkContext) Internal() string {
-	return fmt.Sprintf("%v", c.n.Internal)
+	return strconv.FormatBool(c.n.Internal)
 }
 
 func (c *networkContext) Labels() string {

cli/command/service/formatter.go

@@ -3,6 +3,7 @@ package service
 import (
 	"fmt"
 	"sort"
+	"strconv"
 	"strings"
 	"time"
 
@@ -742,12 +743,12 @@ func (pr portRange) String() string {
 	if pr.pEnd > pr.pStart {
 		pub = fmt.Sprintf("%d-%d", pr.pStart, pr.pEnd)
 	} else {
-		pub = fmt.Sprintf("%d", pr.pStart)
+		pub = strconv.FormatUint(uint64(pr.pStart), 10)
 	}
 	if pr.tEnd > pr.tStart {
 		tgt = fmt.Sprintf("%d-%d", pr.tStart, pr.tEnd)
 	} else {
-		tgt = fmt.Sprintf("%d", pr.tStart)
+		tgt = strconv.FormatUint(uint64(pr.tStart), 10)
 	}
 	return fmt.Sprintf("*:%s->%s/%s", pub, tgt, pr.protocol)
 }

cli/command/service/opts.go

@@ -46,7 +46,7 @@ func (i *Uint64Opt) Type() string {
 // String returns a string repr of this option
 func (i *Uint64Opt) String() string {
 	if i.value != nil {
-		return fmt.Sprintf("%v", *i.value)
+		return strconv.FormatUint(*i.value, 10)
 	}
 	return ""
 }

cli/compose/loader/loader.go

@@ -6,6 +6,7 @@ import (
 	"path/filepath"
 	"reflect"
 	"sort"
+	"strconv"
 	"strings"
 	"time"
 
@@ -717,7 +718,7 @@ var transformServicePort TransformerFunc = func(data interface{}) (interface{},
 		for _, entry := range entries {
 			switch value := entry.(type) {
 			case int:
-				v, err := toServicePortConfigs(fmt.Sprint(value))
+				v, err := toServicePortConfigs(strconv.Itoa(value))
 				if err != nil {
 					return data, err
 				}

cli/compose/types/types.go

@@ -3,6 +3,7 @@ package types
 import (
 	"encoding/json"
 	"fmt"
+	"strconv"
 	"time"
 )
 
@@ -565,7 +566,7 @@ func (e External) MarshalYAML() (interface{}, error) {
 // MarshalJSON makes External implement json.Marshaller
 func (e External) MarshalJSON() ([]byte, error) {
 	if e.Name == "" {
-		return []byte(fmt.Sprintf("%v", e.External)), nil
+		return []byte(strconv.FormatBool(e.External)), nil
 	}
 	return []byte(fmt.Sprintf(`{"name": %q}`, e.Name)), nil
 }