Enforce more lint checks, fix findings (#492)

.golangci.yaml

@@ -1,19 +1,30 @@
 run:
   timeout: 5m
 
-linters:
-  enable:
-    - asciicheck
-    - gosec
-    - prealloc
-    - stylecheck
-    - unconvert
-    - unparam
-  disable:
-    - errcheck
-
 issues:
   exclude-rules:
     - path: test # Excludes /test, *_test.go etc.
       linters:
         - gosec
+
+linters:
+  enable:
+  - asciicheck
+  - deadcode
+  - depguard
+  - errorlint
+  - gofmt
+  - gosec
+  - goimports
+  - importas
+  - prealloc
+  - revive
+  - misspell
+  - stylecheck
+  - tparallel
+  - unconvert
+  - unparam
+  - whitespace
+
+  disable:
+  - errcheck

pkg/build/gobuild.go

@@ -148,7 +148,7 @@ func (g *gobuild) QualifyImport(importpath string) (string, error) {
 		var err error
 		importpath, err = g.qualifyLocalImport(importpath)
 		if err != nil {
-			return "", fmt.Errorf("qualifying local import %s: %v", importpath, err)
+			return "", fmt.Errorf("qualifying local import %s: %w", importpath, err)
 		}
 	}
 	if !strings.HasPrefix(importpath, StrictScheme) {
@@ -187,7 +187,7 @@ func getGoarm(platform v1.Platform) (string, error) {
 	vs := strings.TrimPrefix(platform.Variant, "v")
 	variant, err := strconv.Atoi(vs)
 	if err != nil {
-		return "", fmt.Errorf("cannot parse arm variant %q: %v", platform.Variant, err)
+		return "", fmt.Errorf("cannot parse arm variant %q: %w", platform.Variant, err)
 	}
 	if variant >= 5 {
 		// TODO(golang/go#29373): Allow for 8 in later go versions if this is fixed.
@@ -229,7 +229,7 @@ func build(ctx context.Context, ip string, dir string, platform v1.Platform, con
 
 	env, err := buildEnv(platform, os.Environ(), config.Env)
 	if err != nil {
-		return "", fmt.Errorf("could not create env for %s: %v", ip, err)
+		return "", fmt.Errorf("could not create env for %s: %w", ip, err)
 	}
 	cmd.Env = env
 
@@ -260,7 +260,7 @@ func buildEnv(platform v1.Platform, userEnv, configEnv []string) ([]string, erro
 	if strings.HasPrefix(platform.Architecture, "arm") && platform.Variant != "" {
 		goarm, err := getGoarm(platform)
 		if err != nil {
-			return nil, fmt.Errorf("goarm failure: %v", err)
+			return nil, fmt.Errorf("goarm failure: %w", err)
 		}
 		if goarm != "" {
 			env = append(env, "GOARM="+goarm)
@@ -318,7 +318,7 @@ func tarBinary(name, binary string, creationTime v1.Time, platform *v1.Platform)
 			Mode:    0555,
 			ModTime: creationTime.Time,
 		}); err != nil {
-			return nil, fmt.Errorf("writing dir %q: %v", dir, err)
+			return nil, fmt.Errorf("writing dir %q: %w", dir, err)
 		}
 	}
 
@@ -494,7 +494,7 @@ func (g *gobuild) tarKoData(ref reference, platform *v1.Platform) (*bytes.Buffer
 			Mode:    0555,
 			ModTime: creationTime.Time,
 		}); err != nil {
-			return nil, fmt.Errorf("writing dir %q: %v", dir, err)
+			return nil, fmt.Errorf("writing dir %q: %w", dir, err)
 		}
 	}
 

pkg/build/gobuild_test.go

@@ -19,6 +19,7 @@ package build
 import (
 	"archive/tar"
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -431,7 +432,7 @@ func validateImage(t *testing.T, img v1.Image, baseLayers int64, creationTime v1
 		}
 		defer r.Close()
 		tr := tar.NewReader(r)
-		if _, err := tr.Next(); err == io.EOF {
+		if _, err := tr.Next(); errors.Is(err, io.EOF) {
 			t.Errorf("Layer contained no files")
 		}
 	})
@@ -449,7 +450,7 @@ func validateImage(t *testing.T, img v1.Image, baseLayers int64, creationTime v1
 		tr := tar.NewReader(r)
 		for {
 			header, err := tr.Next()
-			if err == io.EOF {
+			if errors.Is(err, io.EOF) {
 				break
 			} else if err != nil {
 				t.Errorf("Next() = %v", err)

pkg/build/gobuilds.go

@@ -142,7 +142,7 @@ func relativePath(baseDir string, importpath string) (string, error) {
 	}
 	relPath, err := filepath.Rel(baseDir, importpath)
 	if err != nil {
-		return "", fmt.Errorf("cannot determine relative path of baseDir (%q) and local path (%q): %v", baseDir, importpath, err)
+		return "", fmt.Errorf("cannot determine relative path of baseDir (%q) and local path (%q): %w", baseDir, importpath, err)
 	}
 	if strings.HasPrefix(relPath, "..") {
 		// TODO Is this assumption correct?

pkg/build/strict.go

@@ -43,7 +43,6 @@ func (r reference) Path() string {
 func (r reference) String() string {
 	if r.IsStrict() {
 		return StrictScheme + r.Path()
-	} else {
-		return r.Path()
 	}
+	return r.Path()
 }

pkg/commands/apply.go

@@ -90,11 +90,11 @@ func addApply(topLevel *cobra.Command) {
 			bo.InsecureRegistry = po.InsecureRegistry
 			builder, err := makeBuilder(ctx, bo)
 			if err != nil {
-				return fmt.Errorf("error creating builder: %v", err)
+				return fmt.Errorf("error creating builder: %w", err)
 			}
 			publisher, err := makePublisher(po)
 			if err != nil {
-				return fmt.Errorf("error creating publisher: %v", err)
+				return fmt.Errorf("error creating publisher: %w", err)
 			}
 			defer publisher.Close()
 
@@ -121,7 +121,7 @@ func addApply(topLevel *cobra.Command) {
 			// Wire up kubectl stdin to resolveFilesToWriter.
 			stdin, err := kubectlCmd.StdinPipe()
 			if err != nil {
-				return fmt.Errorf("error piping to 'kubectl apply': %v", err)
+				return fmt.Errorf("error piping to 'kubectl apply': %w", err)
 			}
 
 			// Make sure builds are cancelled if kubectl apply fails.
@@ -144,7 +144,7 @@ func addApply(topLevel *cobra.Command) {
 			g.Go(func() error {
 				// Run it.
 				if err := kubectlCmd.Run(); err != nil {
-					return fmt.Errorf("error executing 'kubectl apply': %v", err)
+					return fmt.Errorf("error executing 'kubectl apply': %w", err)
 				}
 				return nil
 			})

pkg/commands/build.go

@@ -63,16 +63,16 @@ func addBuild(topLevel *cobra.Command) {
 			bo.InsecureRegistry = po.InsecureRegistry
 			builder, err := makeBuilder(ctx, bo)
 			if err != nil {
-				return fmt.Errorf("error creating builder: %v", err)
+				return fmt.Errorf("error creating builder: %w", err)
 			}
 			publisher, err := makePublisher(po)
 			if err != nil {
-				return fmt.Errorf("error creating publisher: %v", err)
+				return fmt.Errorf("error creating publisher: %w", err)
 			}
 			defer publisher.Close()
 			images, err := publishImages(ctx, args, publisher, builder)
 			if err != nil {
-				return fmt.Errorf("failed to publish images: %v", err)
+				return fmt.Errorf("failed to publish images: %w", err)
 			}
 			for _, img := range images {
 				fmt.Println(img)

pkg/commands/config.go

@@ -57,7 +57,7 @@ func getBaseImage(platform string, bo *options.BuildOptions) build.GetBase {
 		}
 		ref, err := name.ParseReference(baseImage, nameOpts...)
 		if err != nil {
-			return nil, nil, fmt.Errorf("parsing base image (%q): %v", baseImage, err)
+			return nil, nil, fmt.Errorf("parsing base image (%q): %w", baseImage, err)
 		}
 
 		// For ko.local, look in the daemon.
@@ -128,7 +128,7 @@ func getTimeFromEnv(env string) (*v1.Time, error) {
 
 	seconds, err := strconv.ParseInt(epoch, 10, 64)
 	if err != nil {
-		return nil, fmt.Errorf("the environment variable %s should be the number of seconds since January 1st 1970, 00:00 UTC, got: %v", env, err)
+		return nil, fmt.Errorf("the environment variable %s should be the number of seconds since January 1st 1970, 00:00 UTC, got: %w", env, err)
 	}
 	return &v1.Time{Time: time.Unix(seconds, 0)}, nil
 }

pkg/commands/create.go

@@ -75,11 +75,11 @@ func addCreate(topLevel *cobra.Command) {
 			bo.InsecureRegistry = po.InsecureRegistry
 			builder, err := makeBuilder(ctx, bo)
 			if err != nil {
-				return fmt.Errorf("error creating builder: %v", err)
+				return fmt.Errorf("error creating builder: %w", err)
 			}
 			publisher, err := makePublisher(po)
 			if err != nil {
-				return fmt.Errorf("error creating publisher: %v", err)
+				return fmt.Errorf("error creating publisher: %w", err)
 			}
 			defer publisher.Close()
 
@@ -106,7 +106,7 @@ func addCreate(topLevel *cobra.Command) {
 			// Wire up kubectl stdin to resolveFilesToWriter.
 			stdin, err := kubectlCmd.StdinPipe()
 			if err != nil {
-				return fmt.Errorf("error piping to 'kubectl create': %v", err)
+				return fmt.Errorf("error piping to 'kubectl create': %w", err)
 			}
 
 			// Make sure builds are cancelled if kubectl create fails.
@@ -129,7 +129,7 @@ func addCreate(topLevel *cobra.Command) {
 			g.Go(func() error {
 				// Run it.
 				if err := kubectlCmd.Run(); err != nil {
-					return fmt.Errorf("error executing 'kubectl create': %v", err)
+					return fmt.Errorf("error executing 'kubectl create': %w", err)
 				}
 				return nil
 			})

pkg/commands/deps.go

@@ -16,6 +16,7 @@ package commands
 
 import (
 	"archive/tar"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -80,7 +81,7 @@ If the image was not built using ko, or if it was built without embedding depend
 					// keep reading.
 				}
 				h, err := tr.Next()
-				if err == io.EOF {
+				if errors.Is(err, io.EOF) {
 					return fmt.Errorf("no ko-built executable named %q found", bin)
 				}
 				if err != nil {

pkg/commands/options/build.go

@@ -17,6 +17,7 @@ limitations under the License.
 package options
 
 import (
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -91,15 +92,15 @@ func (bo *BuildOptions) LoadConfig() error {
 	v.AddConfigPath(bo.WorkingDirectory)
 
 	if err := v.ReadInConfig(); err != nil {
-		if _, ok := err.(viper.ConfigFileNotFoundError); !ok {
-			return fmt.Errorf("error reading config file: %v", err)
+		if !errors.As(err, &viper.ConfigFileNotFoundError{}) {
+			return fmt.Errorf("error reading config file: %w", err)
 		}
 	}
 
 	if bo.BaseImage == "" {
 		ref := v.GetString("defaultBaseImage")
 		if _, err := name.ParseReference(ref); err != nil {
-			return fmt.Errorf("'defaultBaseImage': error parsing %q as image reference: %v", ref, err)
+			return fmt.Errorf("'defaultBaseImage': error parsing %q as image reference: %w", ref, err)
 		}
 		bo.BaseImage = ref
 	}
@@ -109,7 +110,7 @@ func (bo *BuildOptions) LoadConfig() error {
 		overrides := v.GetStringMapString("baseImageOverrides")
 		for key, value := range overrides {
 			if _, err := name.ParseReference(value); err != nil {
-				return fmt.Errorf("'baseImageOverrides': error parsing %q as image reference: %v", value, err)
+				return fmt.Errorf("'baseImageOverrides': error parsing %q as image reference: %w", value, err)
 			}
 			baseImageOverrides[key] = value
 		}
@@ -172,7 +173,7 @@ func createBuildConfigMap(workingDirectory string, configs []build.Config) (map[
 
 		pkgs, err := packages.Load(&packages.Config{Mode: packages.NeedName, Dir: baseDir}, localImportPath)
 		if err != nil {
-			return nil, fmt.Errorf("'builds': entry #%d does not contain a valid local import path (%s) for directory (%s): %v", i, localImportPath, baseDir, err)
+			return nil, fmt.Errorf("'builds': entry #%d does not contain a valid local import path (%s) for directory (%s): %w", i, localImportPath, baseDir, err)
 		}
 
 		if len(pkgs) != 1 {

pkg/commands/publisher.go

@@ -38,16 +38,16 @@ func publishImages(ctx context.Context, importpaths []string, pub publish.Interf
 			return nil, err
 		}
 		if err := b.IsSupportedReference(importpath); err != nil {
-			return nil, fmt.Errorf("importpath %q is not supported: %v", importpath, err)
+			return nil, fmt.Errorf("importpath %q is not supported: %w", importpath, err)
 		}
 
 		img, err := b.Build(ctx, importpath)
 		if err != nil {
-			return nil, fmt.Errorf("error building %q: %v", importpath, err)
+			return nil, fmt.Errorf("error building %q: %w", importpath, err)
 		}
 		ref, err := pub.Publish(ctx, img, importpath)
 		if err != nil {
-			return nil, fmt.Errorf("error publishing %s: %v", importpath, err)
+			return nil, fmt.Errorf("error publishing %s: %w", importpath, err)
 		}
 		imgs[importpath] = ref
 	}

pkg/commands/resolve.go

@@ -60,11 +60,11 @@ func addResolve(topLevel *cobra.Command) {
 			bo.InsecureRegistry = po.InsecureRegistry
 			builder, err := makeBuilder(ctx, bo)
 			if err != nil {
-				return fmt.Errorf("error creating builder: %v", err)
+				return fmt.Errorf("error creating builder: %w", err)
 			}
 			publisher, err := makePublisher(po)
 			if err != nil {
-				return fmt.Errorf("error creating publisher: %v", err)
+				return fmt.Errorf("error creating publisher: %w", err)
 			}
 			defer publisher.Close()
 			return resolveFilesToWriter(ctx, builder, publisher, fo, so, os.Stdout)