fix: use filepath.Rel for cross-volume NZB/PAR2 output paths

pkg/postie/postie.go

@@ -255,8 +255,7 @@ func (p *Postie) postInParallel(
 		var par2OutputDir string
 		if p.par2Cfg.MaintainPar2Files != nil && *p.par2Cfg.MaintainPar2Files {
 			// Generate PAR2 files directly in output directory
-			dirPath := filepath.Dir(f.Path)
-			relativePath := strings.TrimPrefix(dirPath, rootDir)
+			relativePath := relativePathFrom(rootDir, f.Path)
 			par2OutputDir = filepath.Join(outputDir, relativePath)
 
 			slog.DebugContext(ctx, "Generating PAR2 files directly in output directory",
@@ -309,11 +308,10 @@ func (p *Postie) postInParallel(
 	}
 
 	// Generate single NZB file for all files
-	dirPath := filepath.Dir(f.Path)
-	dirPath = strings.TrimPrefix(dirPath, rootDir)
+	relativePath := relativePathFrom(rootDir, f.Path)
 
 	// Use the original filename as input for NZB generation
-	nzbPath := filepath.Join(outputDir, dirPath, filepath.Base(f.Path))
+	nzbPath := filepath.Join(outputDir, relativePath, filepath.Base(f.Path))
 	finalPath, err := nzbGen.Generate(nzbPath)
 	if err != nil {
 		return "", fmt.Errorf("error generating NZB file: %w", err)
@@ -366,8 +364,7 @@ func (p *Postie) post(
 		var par2OutputDir string
 		if p.par2Cfg.MaintainPar2Files != nil && *p.par2Cfg.MaintainPar2Files {
 			// Generate PAR2 files directly in output directory
-			dirPath := filepath.Dir(f.Path)
-			relativePath := strings.TrimPrefix(dirPath, rootDir)
+			relativePath := relativePathFrom(rootDir, f.Path)
 			par2OutputDir = filepath.Join(outputDir, relativePath)
 
 			slog.DebugContext(ctx, "Generating PAR2 files directly in output directory",
@@ -401,11 +398,10 @@ func (p *Postie) post(
 	}
 
 	// Generate single NZB file for all files
-	dirPath := filepath.Dir(f.Path)
-	dirPath = strings.TrimPrefix(dirPath, rootDir)
+	relativePath := relativePathFrom(rootDir, f.Path)
 
 	// Use the original filename as input for NZB generation
-	nzbPath := filepath.Join(outputDir, dirPath, filepath.Base(f.Path))
+	nzbPath := filepath.Join(outputDir, relativePath, filepath.Base(f.Path))
 	finalPath, err := nzbGen.Generate(nzbPath)
 	if err != nil {
 		return "", fmt.Errorf("error generating NZB file: %w", err)
@@ -747,3 +743,15 @@ func deriveFolderName(rootDir string, files []fileinfo.FileInfo) string {
 	}
 	return name
 }
+
+// relativePathFrom computes the relative path of filePath's directory from rootDir.
+// Falls back to empty string (placing output directly in outputDir) if paths
+// cannot be made relative (e.g. cross-volume on Windows).
+func relativePathFrom(rootDir, filePath string) string {
+	dirPath := filepath.Dir(filePath)
+	rel, err := filepath.Rel(rootDir, dirPath)
+	if err != nil || rel == "." {
+		return ""
+	}
+	return rel
+}

pkg/postie/postie_crossvolume_test.go

@@ -0,0 +1,127 @@
+package postie
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/javi11/postie/pkg/fileinfo"
+)
+
+// withinDir checks whether path is inside dir.
+func withinDir(path, dir string) bool {
+	cleanPath := filepath.Clean(path)
+	cleanDir := filepath.Clean(dir) + string(filepath.Separator)
+	return strings.HasPrefix(cleanPath, cleanDir)
+}
+
+// TestPostCrossVolumeNZBInOutputDir verifies that non-folder mode (post/postInParallel)
+// places the NZB in the output directory, not the watch (source) directory, even when
+// the two are on different volumes (no shared path prefix).
+func TestPostCrossVolumeNZBInOutputDir(t *testing.T) {
+	watchDir := t.TempDir()
+	outputDir := t.TempDir()
+
+	// Create a source file in the watch directory
+	srcFile := filepath.Join(watchDir, "movie.mkv")
+	if err := os.WriteFile(srcFile, []byte("content"), 0644); err != nil {
+		t.Fatalf("write source file: %v", err)
+	}
+
+	par2mock := &mockPar2Executor{}
+	p := newTestPostie(par2mock, true, false)
+
+	// post() is the sequential (waitForPar2=true) non-folder path
+	nzbPath, err := p.post(context.Background(), fileinfo.FileInfo{
+		Path: srcFile,
+		Size: 7,
+	}, watchDir, outputDir)
+	if err != nil {
+		t.Fatalf("post() returned error: %v", err)
+	}
+
+	// NZB must be inside the output directory
+	if !withinDir(nzbPath, outputDir) {
+		t.Errorf("NZB placed outside output dir:\n  nzbPath:   %s\n  outputDir: %s", nzbPath, outputDir)
+	}
+
+	// NZB must NOT be in the watch directory
+	if withinDir(nzbPath, watchDir) {
+		t.Errorf("NZB leaked into watch dir:\n  nzbPath:  %s\n  watchDir: %s", nzbPath, watchDir)
+	}
+
+	// Verify the file actually exists
+	if _, err := os.Stat(nzbPath); os.IsNotExist(err) {
+		t.Errorf("NZB file does not exist at %q", nzbPath)
+	}
+}
+
+// TestPostInParallelCrossVolumeNZBInOutputDir does the same check for the parallel path.
+func TestPostInParallelCrossVolumeNZBInOutputDir(t *testing.T) {
+	watchDir := t.TempDir()
+	outputDir := t.TempDir()
+
+	srcFile := filepath.Join(watchDir, "movie.mkv")
+	if err := os.WriteFile(srcFile, []byte("content"), 0644); err != nil {
+		t.Fatalf("write source file: %v", err)
+	}
+
+	par2mock := &mockPar2Executor{}
+	p := newTestPostie(par2mock, false, false)
+
+	nzbPath, err := p.postInParallel(context.Background(), fileinfo.FileInfo{
+		Path: srcFile,
+		Size: 7,
+	}, watchDir, outputDir)
+	if err != nil {
+		t.Fatalf("postInParallel() returned error: %v", err)
+	}
+
+	if !withinDir(nzbPath, outputDir) {
+		t.Errorf("NZB placed outside output dir:\n  nzbPath:   %s\n  outputDir: %s", nzbPath, outputDir)
+	}
+
+	if withinDir(nzbPath, watchDir) {
+		t.Errorf("NZB leaked into watch dir:\n  nzbPath:  %s\n  watchDir: %s", nzbPath, watchDir)
+	}
+
+	if _, err := os.Stat(nzbPath); os.IsNotExist(err) {
+		t.Errorf("NZB file does not exist at %q", nzbPath)
+	}
+}
+
+// TestPostCrossVolumeWithSubdirectory verifies that files in a subdirectory of the
+// watch folder maintain their relative path structure in the output directory.
+func TestPostCrossVolumeWithSubdirectory(t *testing.T) {
+	watchDir := t.TempDir()
+	outputDir := t.TempDir()
+
+	// Create a source file in a subdirectory of the watch folder
+	subDir := filepath.Join(watchDir, "subfolder")
+	if err := os.MkdirAll(subDir, 0755); err != nil {
+		t.Fatalf("mkdir subfolder: %v", err)
+	}
+	srcFile := filepath.Join(subDir, "movie.mkv")
+	if err := os.WriteFile(srcFile, []byte("content"), 0644); err != nil {
+		t.Fatalf("write source file: %v", err)
+	}
+
+	par2mock := &mockPar2Executor{}
+	p := newTestPostie(par2mock, true, false)
+
+	nzbPath, err := p.post(context.Background(), fileinfo.FileInfo{
+		Path: srcFile,
+		Size: 7,
+	}, watchDir, outputDir)
+	if err != nil {
+		t.Fatalf("post() returned error: %v", err)
+	}
+
+	// NZB should be in outputDir/subfolder/
+	expectedDir := filepath.Join(outputDir, "subfolder")
+	if filepath.Dir(nzbPath) != expectedDir {
+		t.Errorf("NZB not in expected subdirectory:\n  got:  %s\n  want: %s/", filepath.Dir(nzbPath), expectedDir)
+	}
+}

tests/e2e/helpers_test.go

@@ -111,6 +111,9 @@ func newChromedpCtx(t *testing.T) (context.Context, context.CancelFunc) {
 		chromedp.Flag("headless", true),
 		chromedp.NoSandbox,
 		chromedp.Flag("disable-gpu", true),
+		// Workaround for Chromium ThreadCache crash on newer Linux kernels
+		// (FATAL:scheduler_loop_quarantine_support.h Check failed: ThreadCache::IsValid)
+		chromedp.Flag("disable-features", "PartitionAlloc"),
 	)
 	allocCtx, allocCancel := chromedp.NewExecAllocator(context.Background(), opts...)
 	ctx, cancel := chromedp.NewContext(allocCtx)

tests/e2e/nntp_test.go

@@ -7,12 +7,15 @@ import (
 	"fmt"
 	"net"
 	"strings"
+	"sync"
 	"time"
 )
 
 type fakeNntpServer struct {
-	listener net.Listener
-	port     int
+	listener     net.Listener
+	port         int
+	mu           sync.Mutex
+	articleCount int
 }
 
 func startFakeNntpServer() (*fakeNntpServer, error) {
@@ -43,23 +46,49 @@ func (s *fakeNntpServer) handleConn(conn net.Conn) {
 	// RFC 3977 §5.1 greeting
 	fmt.Fprintf(conn, "200 Postie-test NNTP server ready\r\n")
 
-	scanner := bufio.NewScanner(conn)
-	for scanner.Scan() {
-		line := strings.ToUpper(strings.TrimSpace(scanner.Text()))
-		if line == "" {
+	reader := bufio.NewReader(conn)
+	for {
+		line, err := reader.ReadString('\n')
+		if err != nil {
+			return // connection closed
+		}
+		cmd := strings.ToUpper(strings.TrimSpace(line))
+		if cmd == "" {
 			continue
 		}
 		switch {
-		case strings.HasPrefix(line, "AUTHINFO USER"):
+		case strings.HasPrefix(cmd, "AUTHINFO USER"):
 			fmt.Fprintf(conn, "381 Enter password\r\n")
-		case strings.HasPrefix(line, "AUTHINFO PASS"):
+		case strings.HasPrefix(cmd, "AUTHINFO PASS"):
 			fmt.Fprintf(conn, "281 Authentication accepted\r\n")
-		case line == "CAPABILITIES":
+		case cmd == "CAPABILITIES":
 			fmt.Fprintf(conn, "101 Capability list:\r\nVERSION 2\r\nREADER\r\nPOST\r\nDATE\r\n.\r\n")
-		case line == "DATE":
+		case cmd == "DATE":
 			// nntppool sends DATE as its connectivity ping (RFC 3977 §7.1)
 			fmt.Fprintf(conn, "111 %s\r\n", time.Now().UTC().Format("20060102150405"))
-		case line == "QUIT":
+		case cmd == "POST":
+			// Phase 1: accept article
+			fmt.Fprintf(conn, "340 Send article\r\n")
+			// Phase 2: read article body until lone ".\r\n"
+			for {
+				bodyLine, err := reader.ReadString('\n')
+				if err != nil {
+					return
+				}
+				if strings.TrimRight(bodyLine, "\r\n") == "." {
+					break
+				}
+			}
+			// Extract Message-ID from the article for STAT verification
+			s.mu.Lock()
+			s.articleCount++
+			s.mu.Unlock()
+			fmt.Fprintf(conn, "240 Article posted\r\n")
+		case strings.HasPrefix(cmd, "STAT "):
+			// Post-check: always report article exists
+			msgID := strings.TrimSpace(line[5:])
+			fmt.Fprintf(conn, "223 0 %s\r\n", msgID)
+		case cmd == "QUIT":
 			fmt.Fprintf(conn, "205 closing connection\r\n")
 			return
 		default: