Enhance LocalModule when no go sources found in project root

pkg/gci/gci_test.go

@@ -63,28 +63,58 @@ func readConfig(t *testing.T, configPath string) *config.Config {
 }
 
 func TestRunWithLocalModule(t *testing.T) {
-	moduleDir := filepath.Join("testdata", "module")
-	// files with a corresponding '*.out.go' file containing the expected
-	// result of formatting
-	testedFiles := []string{
-		"main.go",
-		filepath.Join("internal", "foo", "lib.go"),
+	tests := []struct {
+		name      string
+		moduleDir string
+		// files with a corresponding '*.out.go' file containing the expected
+		// result of formatting
+		testedFiles []string
+	}{
+		{
+			name:      `default module test case`,
+			moduleDir: filepath.Join("testdata", "module"),
+			testedFiles: []string{
+				"main.go",
+				filepath.Join("internal", "foo", "lib.go"),
+			},
+		},
+		{
+			name:      `canonical module without go sources in root dir`,
+			moduleDir: filepath.Join("testdata", "module_canonical"),
+			testedFiles: []string{
+				filepath.Join("cmd", "client", "main.go"),
+				filepath.Join("cmd", "server", "main.go"),
+				filepath.Join("internal", "foo", "lib.go"),
+			},
+		},
+		{
+			name:      `non-canonical module without go sources in root dir`,
+			moduleDir: filepath.Join("testdata", "module_noncanonical"),
+			testedFiles: []string{
+				filepath.Join("cmd", "client", "main.go"),
+				filepath.Join("cmd", "server", "main.go"),
+				filepath.Join("internal", "foo", "lib.go"),
+			},
+		},
 	}
-
-	// run subtests for expected module loading behaviour
-	chdir(t, moduleDir)
-	cfg := readConfig(t, "config.yaml")
-
-	for _, path := range testedFiles {
-		t.Run(path, func(t *testing.T) {
-			// *.go -> *.out.go
-			expected, err := os.ReadFile(strings.TrimSuffix(path, ".go") + ".out.go")
-			require.NoError(t, err)
-
-			_, got, err := LoadFormatGoFile(io.File{path}, *cfg)
-
-			require.NoError(t, err)
-			require.Equal(t, string(expected), string(got))
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// run subtests for expected module loading behaviour
+			chdir(t, tt.moduleDir)
+			cfg := readConfig(t, "config.yaml")
+
+			for _, path := range tt.testedFiles {
+				t.Run(path, func(t *testing.T) {
+					// *.go -> *.out.go
+					expected, err := os.ReadFile(strings.TrimSuffix(path, ".go") + ".out.go")
+					require.NoError(t, err)
+
+					_, got, err := LoadFormatGoFile(io.File{path}, *cfg)
+
+					require.NoError(t, err)
+					require.Equal(t, string(expected), string(got))
+				})
+			}
 		})
 	}
 }
@@ -100,6 +130,8 @@ func TestRunWithLocalModuleWithPackageLoadFailure(t *testing.T) {
 }
 
 func TestRunWithLocalModuleWithModuleLookupError(t *testing.T) {
+	t.Skipf("In fact there is no error when no go files found in the project root")
+
 	dir := t.TempDir()
 	// error from trying to list packages under module with no go files
 	configContent := "sections:\n  - LocalModule\n"

pkg/gci/testdata/module_canonical/.gitattributes

@@ -0,0 +1,4 @@
+# try and stop git running on Windows from converting line endings from
+# in all Go files under this directory. This is to avoid inconsistent test
+# results when `gci` strips "\r" characters
+**/*.go eol=lf

pkg/gci/testdata/module_canonical/cmd/client/main.go

@@ -0,0 +1,9 @@
+package main
+
+import (
+	"example.com/service/internal"
+	"example.com/service/internal/bar"
+	"example.com/service/internal/foo"
+	"golang.org/x/net"
+	"log"
+)

pkg/gci/testdata/module_canonical/cmd/client/main.out.go

@@ -0,0 +1,11 @@
+package main
+
+import (
+	"log"
+
+	"golang.org/x/net"
+
+	"example.com/service/internal"
+	"example.com/service/internal/bar"
+	"example.com/service/internal/foo"
+)

pkg/gci/testdata/module_canonical/cmd/server/main.go

@@ -0,0 +1,9 @@
+package main
+
+import (
+	"example.com/service/internal"
+	"example.com/service/internal/bar"
+	"example.com/service/internal/foo"
+	"golang.org/x/net"
+	"log"
+)

pkg/gci/testdata/module_canonical/cmd/server/main.out.go

@@ -0,0 +1,11 @@
+package main
+
+import (
+	"log"
+
+	"golang.org/x/net"
+
+	"example.com/service/internal"
+	"example.com/service/internal/bar"
+	"example.com/service/internal/foo"
+)

pkg/gci/testdata/module_canonical/config.yaml

@@ -0,0 +1,4 @@
+sections:
+  - Standard
+  - Default
+  - LocalModule

pkg/gci/testdata/module_canonical/go.mod

@@ -0,0 +1,3 @@
+module example.com/service
+
+go 1.20

pkg/gci/testdata/module_canonical/internal/bar/lib.go

@@ -0,0 +1 @@
+package bar

pkg/gci/testdata/module_canonical/internal/foo/lib.go

@@ -0,0 +1,6 @@
+package foo
+
+import (
+	"example.com/service/internal/bar"
+	"log"
+)

pkg/gci/testdata/module_canonical/internal/foo/lib.out.go

@@ -0,0 +1,7 @@
+package foo
+
+import (
+	"log"
+
+	"example.com/service/internal/bar"
+)

pkg/gci/testdata/module_canonical/internal/lib.go

@@ -0,0 +1 @@
+package internal

pkg/gci/testdata/module_noncanonical/.gitattributes

@@ -0,0 +1,4 @@
+# try and stop git running on Windows from converting line endings from
+# in all Go files under this directory. This is to avoid inconsistent test
+# results when `gci` strips "\r" characters
+**/*.go eol=lf

pkg/gci/testdata/module_noncanonical/cmd/client/main.go

@@ -0,0 +1,9 @@
+package main
+
+import (
+	"golang.org/x/net"
+	"log"
+	"service/internal"
+	"service/internal/bar"
+	"service/internal/foo"
+)

pkg/gci/testdata/module_noncanonical/cmd/client/main.out.go

@@ -0,0 +1,11 @@
+package main
+
+import (
+	"log"
+
+	"golang.org/x/net"
+
+	"service/internal"
+	"service/internal/bar"
+	"service/internal/foo"
+)

pkg/gci/testdata/module_noncanonical/cmd/server/main.go

@@ -0,0 +1,9 @@
+package main
+
+import (
+	"golang.org/x/net"
+	"log"
+	"service/internal"
+	"service/internal/bar"
+	"service/internal/foo"
+)

pkg/gci/testdata/module_noncanonical/cmd/server/main.out.go

@@ -0,0 +1,11 @@
+package main
+
+import (
+	"log"
+
+	"golang.org/x/net"
+
+	"service/internal"
+	"service/internal/bar"
+	"service/internal/foo"
+)

pkg/gci/testdata/module_noncanonical/config.yaml

@@ -0,0 +1,4 @@
+sections:
+  - Standard
+  - Default
+  - LocalModule

pkg/gci/testdata/module_noncanonical/go.mod

@@ -0,0 +1,3 @@
+module service
+
+go 1.20

pkg/gci/testdata/module_noncanonical/internal/bar/lib.go

@@ -0,0 +1 @@
+package bar

pkg/gci/testdata/module_noncanonical/internal/foo/lib.go

@@ -0,0 +1,6 @@
+package foo
+
+import (
+	"log"
+	"service/internal/bar"
+)

pkg/gci/testdata/module_noncanonical/internal/foo/lib.out.go

@@ -0,0 +1,7 @@
+package foo
+
+import (
+	"log"
+
+	"service/internal/bar"
+)

pkg/gci/testdata/module_noncanonical/internal/lib.go

@@ -0,0 +1 @@
+package internal

pkg/section/local_module.go

@@ -2,8 +2,10 @@ package section
 
 import (
 	"fmt"
+	"os"
 	"strings"
 
+	"golang.org/x/mod/modfile"
 	"golang.org/x/tools/go/packages"
 
 	"github.com/daixiang0/gci/pkg/parse"
@@ -47,7 +49,7 @@ func (m *LocalModule) Configure() error {
 }
 
 func findLocalModules() ([]string, error) {
-	packages, err := packages.Load(
+	pkgs, err := packages.Load(
 		// find the package in the current dir and load its module
 		// NeedFiles so there is some more info in package errors
 		&packages.Config{Mode: packages.NeedModule | packages.NeedFiles},
@@ -59,12 +61,21 @@ func findLocalModules() ([]string, error) {
 
 	uniqueModules := make(map[string]struct{})
 
-	for _, pkg := range packages {
-		if len(pkg.Errors) != 0 {
+	for _, pkg := range pkgs {
+		if len(pkg.Errors) != 0 && !errorsContainListError(pkg.Errors) {
 			return nil, fmt.Errorf("error reading local packages: %v", pkg.Errors)
 		}
 		if pkg.Module != nil {
 			uniqueModules[pkg.Module.Path] = struct{}{}
+		} else {
+			b, err := os.ReadFile("go.mod")
+			if err != nil {
+				return nil, fmt.Errorf("failed to read go.mod file directly: %v", err)
+			}
+
+			name := modfile.ModulePath(b)
+			uniqueModules[name] = struct{}{}
+
 		}
 	}
 
@@ -75,3 +86,13 @@ func findLocalModules() ([]string, error) {
 
 	return modPaths, nil
 }
+
+func errorsContainListError(errors []packages.Error) bool {
+	for _, v := range errors {
+		if v.Kind == packages.ListError {
+			return true
+		}
+	}
+
+	return false
+}