Ignore __MACOSX folder in tool archives when launching core install (#2162)

* Ignore  folder when installing packages

* Propose a small refactoring of the  func

* Add missing license header

Author: alessio-perugini

Diff for: arduino/resources/install.go

@@ -120,19 +120,16 @@ func findPackageRoot(parent *paths.Path) (*paths.Path, error) {
 	if err != nil {
 		return nil, fmt.Errorf(tr("reading package root dir: %s", err))
 	}
-	var root *paths.Path
-	for _, file := range files {
-		if !file.IsDir() {
-			continue
-		}
-		if root == nil {
-			root = file
-		} else {
-			return nil, fmt.Errorf(tr("no unique root dir in archive, found '%[1]s' and '%[2]s'", root, file))
-		}
-	}
-	if root == nil {
+
+	files.FilterDirs()
+	files.FilterOutPrefix("__MACOSX")
+
+	if len(files) == 0 {
 		return nil, fmt.Errorf(tr("files in archive must be placed in a subdirectory"))
 	}
-	return root, nil
+	if len(files) > 1 {
+		return nil, fmt.Errorf(tr("no unique root dir in archive, found '%[1]s' and '%[2]s'", files[0], files[1]))
+	}
+
+	return files[0], nil
 }

Diff for: arduino/resources/install_test.go

@@ -0,0 +1,90 @@
+// This file is part of arduino-cli.
+//
+// Copyright 2023 ARDUINO SA (http://www.arduino.cc/)
+//
+// This software is released under the GNU General Public License version 3,
+// which covers the main part of arduino-cli.
+// The terms of this license can be found at:
+// https://www.gnu.org/licenses/gpl-3.0.en.html
+//
+// You can be released from the requirements of the above licenses by purchasing
+// a commercial license. Buying such a license is mandatory if you want to
+// modify or otherwise use the software for commercial activities involving the
+// Arduino software without disclosing the source code of your own applications.
+// To purchase a commercial license, send an email to [email protected].
+
+package resources
+
+import (
+	"os"
+	"path"
+	"path/filepath"
+	"testing"
+
+	"github.com/arduino/go-paths-helper"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestInstallPlatform(t *testing.T) {
+	t.Run("ignore __MACOSX folder", func(t *testing.T) {
+		testFileName := "platform_with_root_and__MACOSX_folder.tar.bz2"
+		testFilePath := filepath.Join("testdata/valid", testFileName)
+
+		downloadDir, tempPath, destDir := paths.New(t.TempDir()), paths.New(t.TempDir()), paths.New(t.TempDir())
+
+		// copy testfile in the download dir
+		origin, err := os.ReadFile(testFilePath)
+		require.NoError(t, err)
+		require.NoError(t, os.WriteFile(path.Join(downloadDir.String(), testFileName), origin, 0644))
+
+		r := &DownloadResource{
+			ArchiveFileName: testFileName,
+			Checksum:        "SHA-256:600ad56b6260352e0b2cee786f60749e778e179252a0594ba542f0bd1f8adee5",
+			Size:            157,
+		}
+
+		require.NoError(t, r.Install(downloadDir, tempPath, destDir))
+	})
+
+	tests := []struct {
+		testName         string
+		downloadResource *DownloadResource
+		error            string
+	}{
+		{
+			testName: "multiple root folders not allowed",
+			downloadResource: &DownloadResource{
+				ArchiveFileName: "platform_with_multiple_root_folders.tar.bz2",
+				Checksum:        "SHA-256:8b3fc6253c5ac2f3ba684eba0d62bb8a4ee93469fa822f81e2cd7d1b959c4044",
+				Size:            148,
+			},
+			error: "no unique root dir in archive",
+		},
+		{
+			testName: "root folder not present",
+			downloadResource: &DownloadResource{
+				ArchiveFileName: "platform_without_root_folder.tar.bz2",
+				Checksum:        "SHA-256:bc00db9784e20f50d7a5fceccb6bd95ebff4a3e847aac88365b95a6851a24963",
+				Size:            177,
+			},
+			error: "files in archive must be placed in a subdirectory",
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.testName, func(t *testing.T) {
+			downloadDir, tempPath, destDir := paths.New(t.TempDir()), paths.New(t.TempDir()), paths.New(t.TempDir())
+			testFileName := test.downloadResource.ArchiveFileName
+			testFilePath := filepath.Join("testdata/invalid", testFileName)
+
+			// copy testfile in the download dir
+			origin, err := os.ReadFile(testFilePath)
+			require.NoError(t, err)
+			require.NoError(t, os.WriteFile(path.Join(downloadDir.String(), testFileName), origin, 0644))
+
+			err = test.downloadResource.Install(downloadDir, tempPath, destDir)
+			require.Error(t, err)
+			require.Contains(t, err.Error(), test.error)
+		})
+	}
+}