v3.42.34: Add spf13/afero for filesystem abstraction

- New internal/fs package for testable filesystem operations
- In-memory filesystem support for unit testing without disk I/O
- Swappable global FS: SetFS(afero.NewMemMapFs())
- Wrapper functions: ReadFile, WriteFile, Mkdir, Walk, Glob, etc.
- Testing helpers: WithMemFs(), SetupTestDir()
- Comprehensive test suite demonstrating usage
- Upgraded afero from v1.10.0 to v1.15.0

internal/fs/fs_test.go

@@ -0,0 +1,191 @@
+package fs
+
+import (
+	"os"
+	"testing"
+
+	"github.com/spf13/afero"
+)
+
+func TestMemMapFs(t *testing.T) {
+	// Use in-memory filesystem for testing
+	WithMemFs(func(memFs afero.Fs) {
+		// Create a file
+		err := WriteFile("/test/file.txt", []byte("hello world"), 0644)
+		if err != nil {
+			t.Fatalf("WriteFile failed: %v", err)
+		}
+
+		// Read it back
+		content, err := ReadFile("/test/file.txt")
+		if err != nil {
+			t.Fatalf("ReadFile failed: %v", err)
+		}
+
+		if string(content) != "hello world" {
+			t.Errorf("expected 'hello world', got '%s'", string(content))
+		}
+
+		// Check existence
+		exists, err := Exists("/test/file.txt")
+		if err != nil {
+			t.Fatalf("Exists failed: %v", err)
+		}
+		if !exists {
+			t.Error("file should exist")
+		}
+
+		// Check non-existent file
+		exists, err = Exists("/nonexistent.txt")
+		if err != nil {
+			t.Fatalf("Exists failed: %v", err)
+		}
+		if exists {
+			t.Error("file should not exist")
+		}
+	})
+}
+
+func TestSetupTestDir(t *testing.T) {
+	// Create test directory structure
+	testFs := SetupTestDir(map[string]string{
+		"/backups/db1.dump":     "database 1 content",
+		"/backups/db2.dump":     "database 2 content",
+		"/config/settings.json": `{"key": "value"}`,
+	})
+
+	// Verify files exist
+	content, err := afero.ReadFile(testFs, "/backups/db1.dump")
+	if err != nil {
+		t.Fatalf("ReadFile failed: %v", err)
+	}
+	if string(content) != "database 1 content" {
+		t.Errorf("unexpected content: %s", string(content))
+	}
+
+	// Verify directory structure
+	files, err := afero.ReadDir(testFs, "/backups")
+	if err != nil {
+		t.Fatalf("ReadDir failed: %v", err)
+	}
+	if len(files) != 2 {
+		t.Errorf("expected 2 files, got %d", len(files))
+	}
+}
+
+func TestCopyFile(t *testing.T) {
+	WithMemFs(func(memFs afero.Fs) {
+		// Create source file
+		err := WriteFile("/source.txt", []byte("copy me"), 0644)
+		if err != nil {
+			t.Fatalf("WriteFile failed: %v", err)
+		}
+
+		// Copy file
+		err = CopyFile("/source.txt", "/dest.txt")
+		if err != nil {
+			t.Fatalf("CopyFile failed: %v", err)
+		}
+
+		// Verify copy
+		content, err := ReadFile("/dest.txt")
+		if err != nil {
+			t.Fatalf("ReadFile failed: %v", err)
+		}
+		if string(content) != "copy me" {
+			t.Errorf("unexpected content: %s", string(content))
+		}
+	})
+}
+
+func TestFileSize(t *testing.T) {
+	WithMemFs(func(memFs afero.Fs) {
+		data := []byte("12345678901234567890") // 20 bytes
+		err := WriteFile("/sized.txt", data, 0644)
+		if err != nil {
+			t.Fatalf("WriteFile failed: %v", err)
+		}
+
+		size, err := FileSize("/sized.txt")
+		if err != nil {
+			t.Fatalf("FileSize failed: %v", err)
+		}
+		if size != 20 {
+			t.Errorf("expected size 20, got %d", size)
+		}
+	})
+}
+
+func TestTempDir(t *testing.T) {
+	WithMemFs(func(memFs afero.Fs) {
+		// Create temp dir
+		dir, err := TempDir("", "test-")
+		if err != nil {
+			t.Fatalf("TempDir failed: %v", err)
+		}
+
+		// Verify it exists
+		isDir, err := IsDir(dir)
+		if err != nil {
+			t.Fatalf("IsDir failed: %v", err)
+		}
+		if !isDir {
+			t.Error("temp dir should be a directory")
+		}
+
+		// Verify it's empty
+		isEmpty, err := IsEmpty(dir)
+		if err != nil {
+			t.Fatalf("IsEmpty failed: %v", err)
+		}
+		if !isEmpty {
+			t.Error("temp dir should be empty")
+		}
+	})
+}
+
+func TestWalk(t *testing.T) {
+	WithMemFs(func(memFs afero.Fs) {
+		// Create directory structure
+		_ = MkdirAll("/root/a/b", 0755)
+		_ = WriteFile("/root/file1.txt", []byte("1"), 0644)
+		_ = WriteFile("/root/a/file2.txt", []byte("2"), 0644)
+		_ = WriteFile("/root/a/b/file3.txt", []byte("3"), 0644)
+
+		var files []string
+		err := Walk("/root", func(path string, info os.FileInfo, err error) error {
+			if err != nil {
+				return err
+			}
+			if !info.IsDir() {
+				files = append(files, path)
+			}
+			return nil
+		})
+
+		if err != nil {
+			t.Fatalf("Walk failed: %v", err)
+		}
+
+		if len(files) != 3 {
+			t.Errorf("expected 3 files, got %d: %v", len(files), files)
+		}
+	})
+}
+
+func TestGlob(t *testing.T) {
+	WithMemFs(func(memFs afero.Fs) {
+		_ = WriteFile("/data/backup1.dump", []byte("1"), 0644)
+		_ = WriteFile("/data/backup2.dump", []byte("2"), 0644)
+		_ = WriteFile("/data/config.json", []byte("{}"), 0644)
+
+		matches, err := Glob("/data/*.dump")
+		if err != nil {
+			t.Fatalf("Glob failed: %v", err)
+		}
+
+		if len(matches) != 2 {
+			t.Errorf("expected 2 matches, got %d: %v", len(matches), matches)
+		}
+	})
+}