Gci: update the way to call Run()

Signed-off-by: Xiang Dai <[email protected]>

Author: daixiang0

go.mod

@@ -6,7 +6,7 @@ require (
 	github.com/Djarvur/go-err113 v0.0.0-20200511133814-5174e21577d5
 	github.com/OpenPeeDeeP/depguard v1.0.1
 	github.com/bombsimon/wsl/v3 v3.1.0
-	github.com/daixiang0/gci v0.2.2
+	github.com/daixiang0/gci v0.2.3
 	github.com/denis-tingajkin/go-header v0.3.1
 	github.com/fatih/color v1.9.0
 	github.com/go-critic/go-critic v0.5.2

pkg/golinters/gci.go

@@ -1,10 +1,13 @@
 package golinters
 
 import (
+	"bytes"
+	"fmt"
 	"sync"
 
 	"github.com/daixiang0/gci/pkg/gci"
 	"github.com/pkg/errors"
+	"github.com/shazow/go-diff/difflib"
 	"golang.org/x/tools/go/analysis"
 
 	"github.com/golangci/golangci-lint/pkg/golinters/goanalysis"
@@ -16,6 +19,7 @@ const gciName = "gci"
 func NewGci() *goanalysis.Linter {
 	var mu sync.Mutex
 	var resIssues []goanalysis.Issue
+	differ := difflib.New()
 
 	analyzer := &analysis.Analyzer{
 		Name: gciName,
@@ -43,13 +47,17 @@ func NewGci() *goanalysis.Linter {
 			var issues []goanalysis.Issue
 
 			for _, f := range fileNames {
-				diff, err := gci.Run(f, &gci.FlagSet{LocalFlag: localFlag})
+				source, result, err := gci.Run(f, &gci.FlagSet{LocalFlag: localFlag})
 				if err != nil {
 					return nil, err
 				}
-				if diff == nil {
+				if bytes.Equal(source, result) {
 					continue
 				}
+				err = differ.Diff(&out, bytes.NewReader(source), bytes.NewReader(result))
+				if err != nil {
+					return nil, fmt.Errorf("can't get gci diff output: %v", err)
+				}
 
 				is, err := extractIssuesFromPatch(string(diff), lintCtx.Log, lintCtx, gciName)
 				if err != nil {