Allow a comma-separated list of local prefixes, like goimports

main.go

@@ -13,7 +13,7 @@ var (
 	doWrite = flag.Bool("w", false, "doWrite result to (source) file instead of stdout")
 	doDiff  = flag.Bool("d", false, "display diffs instead of rewriting files")
 
-	localFlag string
+	localFlag []string
 
 	exitCode = 0
 )
@@ -27,9 +27,11 @@ func report(err error) {
 }
 
 func parseFlags() []string {
-	flag.StringVar(&localFlag, "local", "", "put imports beginning with this string after 3rd-party packages, only support one string")
+	var localFlagStr string
+	flag.StringVar(&localFlagStr, "local", "", "put imports beginning with this string after 3rd-party packages; comma-separated list")
 
 	flag.Parse()
+	localFlag = gci.ParseLocalFlag(localFlagStr)
 	return flag.Args()
 }
 

pkg/gci/gci.go

@@ -32,7 +32,7 @@ import (
 )
 
 type FlagSet struct {
-	LocalFlag       string
+	LocalFlag       []string
 	DoWrite, DoDiff *bool
 }
 
@@ -42,7 +42,15 @@ type pkg struct {
 	alias   map[string]string
 }
 
-func newPkg(data [][]byte, localFlag string) *pkg {
+// ParseLocalFlag takes a comma-separated list of
+// package-name-prefixes (as passed to the "-local" flag), and splits
+// it in to a list.  This is different than strings.Split in that it
+// handles the empty string and empty entries in the list.
+func ParseLocalFlag(str string) []string {
+	return strings.FieldsFunc(str, func(c rune) bool { return c == ',' })
+}
+
+func newPkg(data [][]byte, localFlag []string) *pkg {
 	listMap := make(map[int][]string)
 	commentMap := make(map[string]string)
 	aliasMap := make(map[string]string)
@@ -156,11 +164,13 @@ func getPkgInfo(line string, comment bool) (string, string, string) {
 	}
 }
 
-func getPkgType(line, localFlag string) int {
+func getPkgType(line string, localFlag []string) int {
 	pkgName := strings.Trim(line, "\"\\`")
 
-	if localFlag != "" && strings.HasPrefix(pkgName, localFlag) {
-		return local
+	for _, localPkg := range localFlag {
+		if strings.HasPrefix(pkgName, localPkg) {
+			return local
+		}
 	}
 
 	if isStandardPackage(pkgName) {

pkg/gci/gci_test.go

@@ -15,31 +15,47 @@ func TestGetPkgType(t *testing.T) {
 		{Line: `"foo/pkg/bar"`, LocalFlag: "foo", ExpectedResult: local},
 		{Line: `"foo/pkg/bar"`, LocalFlag: "bar", ExpectedResult: remote},
 		{Line: `"foo/pkg/bar"`, LocalFlag: "github.com/foo/bar", ExpectedResult: remote},
+		{Line: `"foo/pkg/bar"`, LocalFlag: "github.com/foo", ExpectedResult: remote},
+		{Line: `"foo/pkg/bar"`, LocalFlag: "github.com/bar", ExpectedResult: remote},
+		{Line: `"foo/pkg/bar"`, LocalFlag: "github.com/foo,github.com/bar", ExpectedResult: remote},
+		{Line: `"foo/pkg/bar"`, LocalFlag: "github.com/foo,,github.com/bar", ExpectedResult: remote},
 
 		{Line: `"github.com/foo/bar"`, LocalFlag: "", ExpectedResult: remote},
 		{Line: `"github.com/foo/bar"`, LocalFlag: "foo", ExpectedResult: remote},
 		{Line: `"github.com/foo/bar"`, LocalFlag: "bar", ExpectedResult: remote},
 		{Line: `"github.com/foo/bar"`, LocalFlag: "github.com/foo/bar", ExpectedResult: local},
+		{Line: `"github.com/foo/bar"`, LocalFlag: "github.com/foo", ExpectedResult: local},
+		{Line: `"github.com/foo/bar"`, LocalFlag: "github.com/bar", ExpectedResult: remote},
+		{Line: `"github.com/foo/bar"`, LocalFlag: "github.com/foo,github.com/bar", ExpectedResult: local},
+		{Line: `"github.com/foo/bar"`, LocalFlag: "github.com/foo,,github.com/bar", ExpectedResult: local},
 
 		{Line: `"context"`, LocalFlag: "", ExpectedResult: standard},
 		{Line: `"context"`, LocalFlag: "context", ExpectedResult: local},
 		{Line: `"context"`, LocalFlag: "foo", ExpectedResult: standard},
 		{Line: `"context"`, LocalFlag: "bar", ExpectedResult: standard},
 		{Line: `"context"`, LocalFlag: "github.com/foo/bar", ExpectedResult: standard},
+		{Line: `"context"`, LocalFlag: "github.com/foo", ExpectedResult: standard},
+		{Line: `"context"`, LocalFlag: "github.com/bar", ExpectedResult: standard},
+		{Line: `"context"`, LocalFlag: "github.com/foo,github.com/bar", ExpectedResult: standard},
+		{Line: `"context"`, LocalFlag: "github.com/foo,,github.com/bar", ExpectedResult: standard},
 
 		{Line: `"os/signal"`, LocalFlag: "", ExpectedResult: standard},
 		{Line: `"os/signal"`, LocalFlag: "os/signal", ExpectedResult: local},
 		{Line: `"os/signal"`, LocalFlag: "foo", ExpectedResult: standard},
 		{Line: `"os/signal"`, LocalFlag: "bar", ExpectedResult: standard},
 		{Line: `"os/signal"`, LocalFlag: "github.com/foo/bar", ExpectedResult: standard},
+		{Line: `"os/signal"`, LocalFlag: "github.com/foo", ExpectedResult: standard},
+		{Line: `"os/signal"`, LocalFlag: "github.com/bar", ExpectedResult: standard},
+		{Line: `"os/signal"`, LocalFlag: "github.com/foo,github.com/bar", ExpectedResult: standard},
+		{Line: `"os/signal"`, LocalFlag: "github.com/foo,,github.com/bar", ExpectedResult: standard},
 	}
 
 	for _, tc := range testCases {
 		tc := tc
 		t.Run(fmt.Sprintf("%s:%s", tc.Line, tc.LocalFlag), func(t *testing.T) {
 			t.Parallel()
 
-			result := getPkgType(tc.Line, tc.LocalFlag)
+			result := getPkgType(tc.Line, ParseLocalFlag(tc.LocalFlag))
 			if got, want := result, tc.ExpectedResult; got != want {
 				t.Errorf("bad result: %d, expected: %d", got, want)
 			}