README.md

@@ -52,7 +52,7 @@ Here are some highlights of go-mail's featureset:
 * [X] RFC5322 compliant mail address validation
 * [X] Support for common mail header field generation (Message-ID, Date, Bulk-Precedence, Priority, etc.)
 * [X] Concurrency-safe reusing the same SMTP connection to send multiple mails
-* [X] Support for attachments and inline embeds (from file system, `io.Reader`, `embed.FS` or `fs.FS`)
+* [X] Support for attachments and inline embeds (from file system, `io.Reader` or `embed.FS`)
 * [X] Support for different encodings
 * [X] Middleware support for 3rd-party libraries to alter mail messages
 * [X] Support sending mails via a local sendmail command

msg.go

@@ -12,7 +12,6 @@ import (
 	"fmt"
 	ht "html/template"
 	"io"
-	"io/fs"
 	"mime"
 	"net/mail"
 	"os"
@@ -1963,28 +1962,9 @@ func (m *Msg) AttachTextTemplate(
 //   - https://datatracker.ietf.org/doc/html/rfc2183
 func (m *Msg) AttachFromEmbedFS(name string, fs *embed.FS, opts ...FileOption) error {
 	if fs == nil {
-		return errors.New("embed.FS must not be nil")
+		return fmt.Errorf("embed.FS must not be nil")
 	}
-	return m.AttachFromIOFS(name, *fs, opts...)
+	file, err := fileFromEmbedFS(name, fs)
-}
-
-// AttachFromIOFS attaches a file from a generic file system to the message.
-//
-// This function retrieves a file by name from an fs.FS instance, processes it, and appends it to the
-// message's attachment collection. Additional file options can be provided for further customization.
-//
-// Parameters:
-//   - name: The name of the file to retrieve from the file system.
-//   - iofs: The file system (must not be nil).
-//   - opts: Optional file options to customize the attachment process.
-//
-// Returns:
-//   - An error if the file cannot be retrieved, the fs.FS is nil, or any other issue occurs.
-func (m *Msg) AttachFromIOFS(name string, iofs fs.FS, opts ...FileOption) error {
-	if iofs == nil {
-		return errors.New("fs.FS must not be nil")
-	}
-	file, err := fileFromIOFS(name, iofs)
 	if err != nil {
 		return err
 	}
@@ -2128,28 +2108,9 @@ func (m *Msg) EmbedTextTemplate(
 //   - https://datatracker.ietf.org/doc/html/rfc2183
 func (m *Msg) EmbedFromEmbedFS(name string, fs *embed.FS, opts ...FileOption) error {
 	if fs == nil {
-		return errors.New("embed.FS must not be nil")
+		return fmt.Errorf("embed.FS must not be nil")
 	}
-	return m.EmbedFromIOFS(name, *fs, opts...)
+	file, err := fileFromEmbedFS(name, fs)
-}
-
-// EmbedFromIOFS embeds a file from a generic file system into the message.
-//
-// This function retrieves a file by name from an fs.FS instance, processes it, and appends it to the
-// message's embed collection. Additional file options can be provided for further customization.
-//
-// Parameters:
-//   - name: The name of the file to retrieve from the file system.
-//   - iofs: The file system (must not be nil).
-//   - opts: Optional file options to customize the embedding process.
-//
-// Returns:
-//   - An error if the file cannot be retrieved, the fs.FS is nil, or any other issue occurs.
-func (m *Msg) EmbedFromIOFS(name string, iofs fs.FS, opts ...FileOption) error {
-	if iofs == nil {
-		return errors.New("fs.FS must not be nil")
-	}
-	file, err := fileFromIOFS(name, iofs)
 	if err != nil {
 		return err
 	}
@@ -2705,15 +2666,15 @@ func (m *Msg) addDefaultHeader() {
 	m.SetGenHeader(HeaderMIMEVersion, string(m.mimever))
 }
 
-// fileFromIOFS returns a File pointer from a given file in the provided fs.FS.
+// fileFromEmbedFS returns a File pointer from a given file in the provided embed.FS.
 //
-// This method retrieves a file from the provided io/fs (fs.FS) and returns a File structure
+// This method retrieves a file from the embedded filesystem (embed.FS) and returns a File structure
 // that can be used as an attachment or embed in the email message. The file's content is read when
 // writing to an io.Writer, and the file is identified by its base name.
 //
 // Parameters:
 //   - name: The name of the file to retrieve from the embedded filesystem.
-//   - fs: An instance that satisfies the fs.FS interface
+//   - fs: A pointer to the embed.FS from which the file will be opened.
 //
 // Returns:
 //   - A pointer to the File structure representing the embedded file.
@@ -2721,27 +2682,23 @@ func (m *Msg) addDefaultHeader() {
 //
 // References:
 //   - https://datatracker.ietf.org/doc/html/rfc2183
-func fileFromIOFS(name string, iofs fs.FS) (*File, error) {
+func fileFromEmbedFS(name string, fs *embed.FS) (*File, error) {
-	if iofs == nil {
+	_, err := fs.Open(name)
-		return nil, errors.New("fs.FS is nil")
-	}
-
-	_, err := iofs.Open(name)
 	if err != nil {
-		return nil, fmt.Errorf("failed to open file from fs.FS: %w", err)
+		return nil, fmt.Errorf("failed to open file from embed.FS: %w", err)
 	}
 	return &File{
 		Name:   filepath.Base(name),
 		Header: make(map[string][]string),
 		Writer: func(writer io.Writer) (int64, error) {
-			file, ferr := iofs.Open(name)
+			file, err := fs.Open(name)
-			if ferr != nil {
+			if err != nil {
-				return 0, fmt.Errorf("failed to open file from fs.FS: %w", ferr)
+				return 0, err
 			}
-			numBytes, ferr := io.Copy(writer, file)
+			numBytes, err := io.Copy(writer, file)
-			if ferr != nil {
+			if err != nil {
 				_ = file.Close()
-				return numBytes, fmt.Errorf("failed to copy file from fs.FS to io.Writer: %w", ferr)
+				return numBytes, fmt.Errorf("failed to copy file to io.Writer: %w", err)
 			}
 			return numBytes, file.Close()
 		},

msg_test.go

@@ -4970,75 +4970,6 @@ func TestMsg_AttachFromEmbedFS(t *testing.T) {
 	})
 }
 
-func TestMsg_AttachFromIOFS(t *testing.T) {
-	t.Run("AttachFromIOFS successful", func(t *testing.T) {
-		message := NewMsg()
-		if message == nil {
-			t.Fatal("message is nil")
-		}
-		if err := message.AttachFromIOFS("testdata/attachment.txt", efs,
-			WithFileName("attachment.txt")); err != nil {
-			t.Fatalf("failed to attach from embed FS: %s", err)
-		}
-		attachments := message.GetAttachments()
-		if len(attachments) != 1 {
-			t.Fatalf("failed to retrieve attachments list")
-		}
-		if attachments[0] == nil {
-			t.Fatal("expected attachment to be not nil")
-		}
-		if attachments[0].Name != "attachment.txt" {
-			t.Errorf("expected attachment name to be %s, got: %s", "attachment.txt", attachments[0].Name)
-		}
-		messageBuf := bytes.NewBuffer(nil)
-		_, err := attachments[0].Writer(messageBuf)
-		if err != nil {
-			t.Errorf("writer func failed: %s", err)
-		}
-		got := strings.TrimSpace(messageBuf.String())
-		if !strings.EqualFold(got, "This is a test attachment") {
-			t.Errorf("expected message body to be %s, got: %s", "This is a test attachment", got)
-		}
-	})
-	t.Run("AttachFromIOFS with invalid path", func(t *testing.T) {
-		message := NewMsg()
-		if message == nil {
-			t.Fatal("message is nil")
-		}
-		err := message.AttachFromIOFS("testdata/invalid.txt", efs, WithFileName("attachment.txt"))
-		if err == nil {
-			t.Fatal("expected error, got nil")
-		}
-	})
-	t.Run("AttachFromIOFS with nil embed FS", func(t *testing.T) {
-		message := NewMsg()
-		if message == nil {
-			t.Fatal("message is nil")
-		}
-		err := message.AttachFromIOFS("testdata/invalid.txt", nil, WithFileName("attachment.txt"))
-		if err == nil {
-			t.Fatal("expected error, got nil")
-		}
-	})
-	t.Run("AttachFromIOFS with fs.FS fails on copy", func(t *testing.T) {
-		message := NewMsg()
-		if message == nil {
-			t.Fatal("message is nil")
-		}
-		if err := message.AttachFromIOFS("testdata/attachment.txt", efs); err != nil {
-			t.Fatalf("failed to attach file from fs.FS: %s", err)
-		}
-		attachments := message.GetAttachments()
-		if len(attachments) != 1 {
-			t.Fatalf("failed to get attachments, expected 1, got: %d", len(attachments))
-		}
-		_, err := attachments[0].Writer(failReadWriteSeekCloser{})
-		if err == nil {
-			t.Error("writer func expected to fail, but didn't")
-		}
-	})
-}
-
 func TestMsg_EmbedFile(t *testing.T) {
 	t.Run("EmbedFile with file", func(t *testing.T) {
 		message := NewMsg()
@@ -5504,58 +5435,6 @@ func TestMsg_EmbedFromEmbedFS(t *testing.T) {
 	})
 }
 
-func TestMsg_EmbedFromIOFS(t *testing.T) {
-	t.Run("EmbedFromIOFS successful", func(t *testing.T) {
-		message := NewMsg()
-		if message == nil {
-			t.Fatal("message is nil")
-		}
-		if err := message.EmbedFromIOFS("testdata/embed.txt", efs,
-			WithFileName("embed.txt")); err != nil {
-			t.Fatalf("failed to embed from embed FS: %s", err)
-		}
-		embeds := message.GetEmbeds()
-		if len(embeds) != 1 {
-			t.Fatalf("failed to retrieve embeds list")
-		}
-		if embeds[0] == nil {
-			t.Fatal("expected embed to be not nil")
-		}
-		if embeds[0].Name != "embed.txt" {
-			t.Errorf("expected embed name to be %s, got: %s", "embed.txt", embeds[0].Name)
-		}
-		messageBuf := bytes.NewBuffer(nil)
-		_, err := embeds[0].Writer(messageBuf)
-		if err != nil {
-			t.Errorf("writer func failed: %s", err)
-		}
-		got := strings.TrimSpace(messageBuf.String())
-		if !strings.EqualFold(got, "This is a test embed") {
-			t.Errorf("expected message body to be %s, got: %s", "This is a test embed", got)
-		}
-	})
-	t.Run("EmbedFromIOFS with invalid path", func(t *testing.T) {
-		message := NewMsg()
-		if message == nil {
-			t.Fatal("message is nil")
-		}
-		err := message.EmbedFromIOFS("testdata/invalid.txt", efs, WithFileName("embed.txt"))
-		if err == nil {
-			t.Fatal("expected error, got nil")
-		}
-	})
-	t.Run("EmbedFromIOFS with nil embed FS", func(t *testing.T) {
-		message := NewMsg()
-		if message == nil {
-			t.Fatal("message is nil")
-		}
-		err := message.EmbedFromIOFS("testdata/invalid.txt", nil, WithFileName("embed.txt"))
-		if err == nil {
-			t.Fatal("expected error, got nil")
-		}
-	})
-}
-
 func TestMsg_Reset(t *testing.T) {
 	message := NewMsg()
 	if message == nil {
@@ -6561,15 +6440,6 @@ func TestMsg_addDefaultHeader(t *testing.T) {
 	})
 }
 
-func TestMsg_fileFromIOFS(t *testing.T) {
-	t.Run("file from fs.FS where fs is nil ", func(t *testing.T) {
-		_, err := fileFromIOFS("testfile.txt", nil)
-		if err == nil {
-			t.Fatal("expected error for fs.FS that is nil")
-		}
-	})
-}
-
 // uppercaseMiddleware is a middleware type that transforms the subject to uppercase.
 type uppercaseMiddleware struct{}