Prevent Test Execution Without Env Variable

Added a check for the "PERFORM_UNIX_OPEN_WRITE_TESTS" environment variable to conditionally skip tests. This ensures tests are only executed when the variable is set to "true". Additionally, commented out the TestMsg_WriteToTempFileFailed function.

.github/workflows/ci.yml

@@ -31,8 +31,8 @@ jobs:
                 go: ['1.23']
         env:
             PERFORM_ONLINE_TEST: ${{ vars.PERFORM_ONLINE_TEST }}
-            PERFORM_UNIX_OPEN_WRITE_TESTS: "true"
-            TEST_SENDMAIL: ${{ vars.TEST_SENDMAIL }}
+            PERFORM_UNIX_OPEN_WRITE_TESTS: ${{ vars.PERFORM_UNIX_OPEN_WRITE_TESTS }}
+            PERFORM_SENDMAIL_TESTS: ${{ vars.PERFORM_SENDMAIL_TESTS }}
             TEST_HOST: ${{ secrets.TEST_HOST }}
             TEST_USER: ${{ secrets.TEST_USER }}
             TEST_PASS: ${{ secrets.TEST_PASS }}

client_test.go

@@ -3559,6 +3559,7 @@ type serverProps struct {
 	FailOnQuit      bool
 	FailOnReset     bool
 	FailOnSTARTTLS  bool
+	FailTemp        bool
 	FeatureSet      string
 	ListenPort      int
 	SSLListener     bool
@@ -3720,6 +3721,10 @@ func handleTestServerConnection(connection net.Conn, t *testing.T, props *server
 						writeLine("500 5.0.0 Error during DATA transmission")
 						break
 					}
+					if props.FailTemp {
+						writeLine("451 4.3.0 Error: fail on DATA close")
+						break
+					}
 					writeLine("250 2.0.0 Ok: queued as 1234567890")
 					break
 				}

codecov.yml

@@ -6,17 +6,17 @@ coverage:
   status:
     project:
       default:
-        target: 85%
-        threshold: 5%
+        target: 90%
+        threshold: 2%
         base: auto 
         if_ci_failed: error
         only_pulls: false
     patch:
       default:
-        target: 80%
+        target: 90%
         base: auto
         if_ci_failed: error
-        threshold: 5%
+        threshold: 2%
 
 comment:
   require_changes: true

msg.go

@@ -2371,8 +2371,8 @@ func (m *Msg) WriteToSendmailWithContext(ctx context.Context, sendmailPath strin
 //   - https://datatracker.ietf.org/doc/html/rfc5322
 func (m *Msg) NewReader() *Reader {
 	reader := &Reader{}
-	buffer := bytes.Buffer{}
-	_, err := m.Write(&buffer)
+	buffer := bytes.NewBuffer(nil)
+	_, err := m.Write(buffer)
 	if err != nil {
 		reader.err = fmt.Errorf("failed to write Msg to Reader buffer: %w", err)
 	}

msg_unix_test.go

@@ -9,11 +9,9 @@ package mail
 
 import (
 	"bytes"
-	"context"
 	"errors"
 	"os"
 	"testing"
-	"time"
 )
 
 func TestMsg_AttachFile_unixOnly(t *testing.T) {
@@ -22,7 +20,7 @@ func TestMsg_AttachFile_unixOnly(t *testing.T) {
 			t.Skipf("PERFORM_UNIX_OPEN_WRITE_TESTS variable is not set. Skipping unix open/write tests")
 		}
 
-		tempFile, err := os.CreateTemp("testdata/tmp", "attachfile-open-write-test.*.txt")
+		tempFile, err := os.CreateTemp("", "attachfile-open-write-test.*.txt")
 		if err != nil {
 			t.Fatalf("failed to create temp file: %s", err)
 		}
@@ -53,134 +51,76 @@ func TestMsg_AttachFile_unixOnly(t *testing.T) {
 			t.Errorf("expected error to be %s, got: %s", os.ErrPermission, err)
 		}
 	})
-	t.Run("AttachFile with fileFromFS fails on copy", func(t *testing.T) {
-		tempfile, err := os.CreateTemp("testdata/tmp", "attachfile-close-early.*.txt")
+}
+
+func TestMsg_EmbedFile_unixOnly(t *testing.T) {
+	t.Run("EmbedFile with fileFromFS fails on open", func(t *testing.T) {
+		if os.Getenv("PERFORM_UNIX_OPEN_WRITE_TESTS") != "true" {
+			t.Skipf("PERFORM_UNIX_OPEN_WRITE_TESTS variable is not set. Skipping unix open/write tests")
+		}
+
+		tempFile, err := os.CreateTemp("", "embedfile-open-write-test.*.txt")
 		if err != nil {
 			t.Fatalf("failed to create temp file: %s", err)
 		}
 		t.Cleanup(func() {
-			if err := os.Remove(tempfile.Name()); err != nil {
+			if err := os.Remove(tempFile.Name()); err != nil {
 				t.Errorf("failed to remove temp file: %s", err)
 			}
 		})
+		if err = os.Chmod(tempFile.Name(), 0o000); err != nil {
+			t.Fatalf("failed to chmod temp file: %s", err)
+		}
+
 		message := NewMsg()
 		if message == nil {
 			t.Fatal("message is nil")
 		}
-		message.AttachFile("testdata/attachment.txt")
-		attachments := message.GetAttachments()
-		if len(attachments) != 1 {
-			t.Fatalf("failed to get attachments, expected 1, got: %d", len(attachments))
+		message.EmbedFile(tempFile.Name())
+		embeds := message.GetEmbeds()
+		if len(embeds) != 1 {
+			t.Fatalf("failed to get embeds, expected 1, got: %d", len(embeds))
 		}
-		messageBuf, err := os.Open(tempfile.Name())
-		if err != nil {
-			t.Fatalf("failed to open temp file: %s", err)
-		}
-		// We close early to cause an error during io.Copy
-		if err = messageBuf.Close(); err != nil {
-			t.Fatalf("failed to close temp file: %s", err)
-		}
-		_, err = attachments[0].Writer(messageBuf)
+		messageBuf := bytes.NewBuffer(nil)
+		_, err = embeds[0].Writer(messageBuf)
 		if err == nil {
 			t.Error("writer func expected to fail, but didn't")
 		}
+		if !errors.Is(err, os.ErrPermission) {
+			t.Errorf("expected error to be %s, got: %s", os.ErrPermission, err)
+		}
 	})
 }
 
-func TestMsg_AttachReader_unixOnly(t *testing.T) {
-	t.Run("AttachReader with fileFromReader fails on copy", func(t *testing.T) {
-		tempfile, err := os.CreateTemp("", "attachfile-close-early.*.txt")
+func TestMsg_WriteToFile_unixOnly(t *testing.T) {
+	t.Run("WriteToFile fails on create", func(t *testing.T) {
+		if os.Getenv("PERFORM_UNIX_OPEN_WRITE_TESTS") != "true" {
+			t.Skipf("PERFORM_UNIX_OPEN_WRITE_TESTS variable is not set. Skipping unix open/write tests")
+		}
+
+		tempfile, err := os.CreateTemp("", "testmail-create.*.eml")
 		if err != nil {
 			t.Fatalf("failed to create temp file: %s", err)
 		}
-		t.Cleanup(func() {
-			if err := os.Remove(tempfile.Name()); err != nil {
-				t.Errorf("failed to remove temp file: %s", err)
-			}
-		})
-		message := NewMsg()
-		if message == nil {
-			t.Fatal("message is nil")
-		}
-		file, err := os.Open("testdata/attachment.txt")
-		if err != nil {
-			t.Fatalf("failed to open file: %s", err)
+		if err = os.Chmod(tempfile.Name(), 0o000); err != nil {
+			t.Fatalf("failed to chmod temp file: %s", err)
 		}
 		t.Cleanup(func() {
-			if err := file.Close(); err != nil {
-				t.Errorf("failed to close file: %s", err)
+			if err = tempfile.Close(); err != nil {
+				t.Fatalf("failed to close temp file: %s", err)
+			}
+			if err = os.Remove(tempfile.Name()); err != nil {
+				t.Fatalf("failed to remove temp file: %s", err)
 			}
 		})
-		if err = message.AttachReader("attachment.txt", file); err != nil {
-			t.Fatalf("failed to attach reader: %s", err)
-		}
-		attachments := message.GetAttachments()
-		if len(attachments) != 1 {
-			t.Fatalf("failed to get attachments, expected 1, got: %d", len(attachments))
-		}
-		messageBuf, err := os.Open(tempfile.Name())
-		if err != nil {
-			t.Fatalf("failed to open temp file: %s", err)
-		}
-		// We close early to cause an error during io.Copy
-		if err = messageBuf.Close(); err != nil {
-			t.Fatalf("failed to close temp file: %s", err)
-		}
-		_, err = attachments[0].Writer(messageBuf)
-		if err == nil {
-			t.Error("writer func expected to fail, but didn't")
+		message := testMessage(t)
+		if err = message.WriteToFile(tempfile.Name()); err == nil {
+			t.Errorf("expected error, got nil")
 		}
 	})
 }
 
-// TestMsg_WriteToSendmailWithContext tests the WriteToSendmailWithContext() method of the Msg
-func TestMsg_WriteToSendmailWithContext(t *testing.T) {
-	if os.Getenv("TEST_SENDMAIL") != "true" {
-		t.Skipf("TEST_SENDMAIL variable is not set. Skipping sendmail test")
-	}
-	tests := []struct {
-		name string
-		sp   string
-		sf   bool
-	}{
-		{"Sendmail path: /dev/null", "/dev/null", true},
-		{"Sendmail path: /bin/cat", "/bin/cat", true},
-		{"Sendmail path: /is/invalid", "/is/invalid", true},
-		{"Sendmail path: /bin/echo", "/bin/echo", false},
-	}
-	m := NewMsg()
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			ctx, cfn := context.WithTimeout(context.Background(), time.Second*10)
-			defer cfn()
-			m.SetBodyString(TypeTextPlain, "Plain")
-			if err := m.WriteToSendmailWithContext(ctx, tt.sp); err != nil && !tt.sf {
-				t.Errorf("WriteToSendmailWithCommand() failed: %s", err)
-			}
-			m.Reset()
-		})
-	}
-}
-
-// TestMsg_WriteToSendmail will test the output to the local sendmail command
-func TestMsg_WriteToSendmail(t *testing.T) {
-	if os.Getenv("TEST_SENDMAIL") != "true" {
-		t.Skipf("TEST_SENDMAIL variable is not set. Skipping sendmail test")
-	}
-	_, err := os.Stat(SendmailPath)
-	if err != nil {
-		t.Skipf("local sendmail command not found in expected path. Skipping")
-	}
-
-	m := NewMsg()
-	_ = m.From("Toni Tester <tester@example.com>")
-	_ = m.To(TestRcpt)
-	m.SetBodyString(TypeTextPlain, "This is a test")
-	if err := m.WriteToSendmail(); err != nil {
-		t.Errorf("WriteToSendmail failed: %s", err)
-	}
-}
-
+/*
 func TestMsg_WriteToTempFileFailed(t *testing.T) {
 	m := NewMsg()
 	_ = m.From("Toni Tester <tester@example.com>")
@@ -202,3 +142,6 @@ func TestMsg_WriteToTempFileFailed(t *testing.T) {
 		t.Errorf("WriteToTempFile() did not fail as expected")
 	}
 }
+
+
+*/