Skip imports ordering and formatting for generated files(by default).…

… Option for the feature is added (#90)

closes #81

README.md

@@ -52,6 +52,10 @@ goimports-reviser -rm-unused -set-alias -format ./...
 ### Options:
 ```text
 Usage of goimports-reviser:
+  -apply-to-generated-files
+        Apply imports sorting and formatting(if the option is set) to generated files. Generated file is a file with first comment which starts with comment '// Code generated'. Optional parameter.
+  -company-prefixes string
+        Company package prefixes which will be placed after 3rd-party group by default(if defined). Values should be comma-separated. Optional parameters.
   -format
         Option will perform additional formatting. Optional parameter.
   -imports-order string
@@ -62,9 +66,7 @@ Usage of goimports-reviser:
         project - your local project dependencies. 
         Optional parameter. (default "std,general,company,project")
   -list-diff
-    	Option will list-diff files whose formatting differs from goimports-reviser. Optional parameter.
-  -company-prefixes string
-        Company package prefixes which will be placed after 3rd-party group(if defined). Values should be comma-separated. Optional parameters.
+        Option will list files whose formatting differs from goimports-reviser. Optional parameter.
   -output string
         Can be "file", "write" or "stdout". Whether to write the formatted content back to the file or to stdout. When "write" together with "-list-diff" will list the file name and write back to the file. Optional parameter. (default "file")
   -project-name string
@@ -76,7 +78,7 @@ Usage of goimports-reviser:
   -set-alias
         Set alias for versioned package names, like 'github.com/go-pg/pg/v9'. In this case import will be set as 'pg "github.com/go-pg/pg/v9"'. Optional parameter.
   -set-exit-status
-    	set the exit status to 1 if a change is needed/made. Optional parameter.
+        set the exit status to 1 if a change is needed/made. Optional parameter.
   -use-cache
         Use cache to improve performance. Optional parameter.
 ```

main.go

@@ -12,7 +12,7 @@ import (
 	"path/filepath"
 	"strings"
 
-	"github.com/mitchellh/go-homedir"
+	homedir "github.com/mitchellh/go-homedir"
 	"github.com/pkg/errors"
 
 	"github.com/incu6us/goimports-reviser/v3/helper"
@@ -32,6 +32,7 @@ const (
 	setExitStatusArg       = "set-exit-status"
 	recursiveArg           = "recursive"
 	useCacheArg            = "use-cache"
+	applyToGeneratedFiles  = "apply-to-generated-files"
 
 	// Deprecated options
 	localArg    = "local"
@@ -45,14 +46,15 @@ var (
 	SourceURL string
 	GoVersion string
 
-	shouldShowVersion         *bool
-	shouldRemoveUnusedImports *bool
-	shouldSetAlias            *bool
-	shouldFormat              *bool
-	listFileName              *bool
-	setExitStatus             *bool
-	isRecursive               *bool
-	isUseCache                *bool
+	shouldShowVersion           *bool
+	shouldRemoveUnusedImports   *bool
+	shouldSetAlias              *bool
+	shouldFormat                *bool
+	shouldApplyToGeneratedFiles *bool
+	listFileName                *bool
+	setExitStatus               *bool
+	isRecursive                 *bool
+	isUseCache                  *bool
 )
 
 var (
@@ -95,7 +97,7 @@ func init() {
 		&output,
 		outputArg,
 		"file",
-		`Can be "file", "write" or "stdout". Whether to write the formatted content back to the file or to stdout. When "write" together with "-list" will list the file name and write back to the file. Optional parameter.`,
+		`Can be "file", "write" or "stdout". Whether to write the formatted content back to the file or to stdout. When "write" together with "-list-diff" will list the file name and write back to the file. Optional parameter.`,
 	)
 
 	flag.StringVar(
@@ -105,7 +107,7 @@ func init() {
 		`Your imports groups can be sorted in your way. 
 std - std import group; 
 general - libs for general purpose; 
-company - inter-org libs(if you set '-local'-option, then 4th group will be split separately. In other case, it will be the part of general purpose libs); 
+company - inter-org or your company libs(if you set '-company-prefixes'-option, then 4th group will be split separately. In other case, it will be the part of general purpose libs); 
 project - your local project dependencies. 
 Optional parameter.`,
 	)
@@ -153,6 +155,12 @@ Optional parameter.`,
 		"Use cache to improve performance. Optional parameter.",
 	)
 
+	shouldApplyToGeneratedFiles = flag.Bool(
+		applyToGeneratedFiles,
+		false,
+		"Apply imports sorting and formatting(if the option is set) to generated files. Generated file is a file with first comment which starts with comment '// Code generated'. Optional parameter.",
+	)
+
 	if Tag != "" {
 		shouldShowVersion = flag.Bool(
 			versionArg,
@@ -219,6 +227,10 @@ func main() {
 		options = append(options, reviser.WithCodeFormatting)
 	}
 
+	if shouldApplyToGeneratedFiles != nil && !*shouldApplyToGeneratedFiles {
+		options = append(options, reviser.WithSkipGeneratedFile)
+	}
+
 	if localPkgPrefixes != "" {
 		if companyPkgPrefixes != "" {
 			companyPkgPrefixes = localPkgPrefixes

reviser/file.go

@@ -28,6 +28,7 @@ type SourceFile struct {
 	shouldRemoveUnusedImports      bool
 	shouldUseAliasForVersionSuffix bool
 	shouldFormatCode               bool
+	shouldSkipAutoGenerated        bool
 	companyPackagePrefixes         []string
 	importsOrders                  ImportsOrders
 
@@ -70,6 +71,10 @@ func (f *SourceFile) Fix(options ...SourceFileOption) ([]byte, bool, error) {
 		return nil, false, err
 	}
 
+	if f.shouldSkipAutoGenerated && isFileAutoGenerate(pf) {
+		return originalContent, false, nil
+	}
+
 	importsWithMetadata, err := f.parseImports(pf)
 	if err != nil {
 		return nil, false, err
@@ -103,6 +108,20 @@ func (f *SourceFile) Fix(options ...SourceFileOption) ([]byte, bool, error) {
 	return formattedContent, !bytes.Equal(originalContent, formattedContent), nil
 }
 
+func isFileAutoGenerate(pf *ast.File) bool {
+	for _, comment := range pf.Comments {
+		for _, c := range comment.List {
+			if c.Slash == 1 && strings.HasPrefix(c.Text, "// Code generated") {
+				return true
+			}
+			if c.Slash > 1 {
+				return false
+			}
+		}
+	}
+	return false
+}
+
 func (f *SourceFile) formatDecls(file *ast.File) {
 	if !f.shouldFormatCode {
 		return

reviser/file_option.go

@@ -44,3 +44,10 @@ func WithImportsOrder(orders []ImportsOrder) SourceFileOption {
 		return nil
 	}
 }
+
+// WithSkipGeneratedFile will skip formatting and imports sorting for auto-generated file which starts with
+// comment on first line: `// Code generated`
+func WithSkipGeneratedFile(f *SourceFile) error {
+	f.shouldSkipAutoGenerated = true
+	return nil
+}

reviser/file_test.go

@@ -53,6 +53,45 @@ import (
 	"github.com/incu6us/goimports-reviser/testdata/innderpkg"
 )
 
+// nolint:gomnd
+`,
+			wantChange: true,
+			wantErr:    false,
+		},
+
+		{
+			name: "success with auto-generated",
+			args: args{
+				projectName: "github.com/incu6us/goimports-reviser",
+				filePath:    "./testdata/example.go",
+				fileContent: `// Code generated by some tool
+package testdata
+
+import (
+	"log"
+
+	"github.com/incu6us/goimports-reviser/testdata/innderpkg"
+
+	"bytes"
+
+	"github.com/pkg/errors"
+)
+
+// nolint:gomnd
+`,
+			},
+			want: `// Code generated by some tool
+package testdata
+
+import (
+	"bytes"
+	"log"
+
+	"github.com/pkg/errors"
+
+	"github.com/incu6us/goimports-reviser/testdata/innderpkg"
+)
+
 // nolint:gomnd
 `,
 			wantChange: true,
@@ -1404,3 +1443,77 @@ func test1() {}
 		})
 	}
 }
+
+func TestSourceFile_Fix_WithSkipGeneratedFile(t *testing.T) {
+	type args struct {
+		projectName string
+		filePath    string
+		fileContent string
+	}
+
+	tests := []struct {
+		name       string
+		args       args
+		want       string
+		wantChange bool
+		wantErr    bool
+	}{
+		{
+			name: "success with generated file",
+			args: args{
+				projectName: "github.com/incu6us/goimports-reviser",
+				filePath:    "./testdata/example.go",
+				fileContent: `// Code generated by some tool
+package testdata
+
+import (
+	"log"
+
+	"github.com/incu6us/goimports-reviser/testdata/innderpkg"
+
+	"bytes"
+
+	"github.com/pkg/errors"
+)
+
+// nolint:gomnd
+`,
+			},
+			want: `// Code generated by some tool
+package testdata
+
+import (
+	"log"
+
+	"github.com/incu6us/goimports-reviser/testdata/innderpkg"
+
+	"bytes"
+
+	"github.com/pkg/errors"
+)
+
+// nolint:gomnd
+`,
+			wantChange: false,
+			wantErr:    false,
+		},
+	}
+	for _, tt := range tests {
+		if tt.args.filePath != StandardInput && !strings.Contains(tt.args.filePath, "does-not-exist") {
+			if err := ioutil.WriteFile(tt.args.filePath, []byte(tt.args.fileContent), 0644); err != nil {
+				t.Errorf("write test file failed: %s", err)
+			}
+		}
+
+		t.Run(tt.name, func(t *testing.T) {
+			got, hasChange, err := NewSourceFile(tt.args.projectName, tt.args.filePath).Fix(WithSkipGeneratedFile)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("Fix() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+
+			assert.Equal(t, tt.wantChange, hasChange)
+			assert.Equal(t, tt.want, string(got))
+		})
+	}
+}