fixup: added handling of trailing tabs/spaces in password files. Causes edge case failure for passwords with intentional trailing whitespace

Signed-off-by: kaldun-tech <tsmereka@protonmail.com>

Author: kaldun-tech

loopdb/secret.go

@@ -31,9 +31,10 @@ func (s *Secret) UnmarshalFlag(value string) error {
 			return fmt.Errorf("failed to read secret file %s: %w",
 				filePath, err)
 		}
-		// Trim trailing newlines. Trim both \r and \n to handle
-		// files created on Windows (CRLF) or Unix (LF).
-		*s = Secret(strings.TrimRight(string(content), "\r\n"))
+		// Trim trailing whitespace (spaces, tabs, newlines) to handle
+		// files created on Windows (CRLF) or Unix (LF), and to avoid
+		// invisible trailing spaces causing authentication failures.
+		*s = Secret(strings.TrimRight(string(content), " \t\r\n"))
 
 		return nil
 	}

loopdb/secret_test.go

@@ -74,6 +74,20 @@ func TestSecretUnmarshalFlag(t *testing.T) {
 		require.Equal(t, Secret("secretpassword"), s)
 	})
 
+	t.Run("file with trailing whitespace", func(t *testing.T) {
+		t.Parallel()
+
+		tmpDir := t.TempDir()
+		passFile := filepath.Join(tmpDir, "password.txt")
+		err := os.WriteFile(passFile, []byte("secretpassword \t\n"), 0600)
+		require.NoError(t, err)
+
+		var s Secret
+		err = s.UnmarshalFlag("@" + passFile)
+		require.NoError(t, err)
+		require.Equal(t, Secret("secretpassword"), s)
+	})
+
 	t.Run("empty file", func(t *testing.T) {
 		t.Parallel()