Return Error instead of CommandError

This patch changes all public functions to return the Error enum instead
of the CommandError enum.  This breaks the tests which will be fixed
with the next patch.

This patch also adds a placeholder variant Error::CommandError and a
placeholder enum CommandError to make the transition to a new
nitrokey-test version easier.

1 files changed, 11 insertions, 0 deletions

diff --git a/src/error.rs b/src/error.rs
index 89c4c82..3f60af2 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -9,6 +9,8 @@ use std::result;
 pub enum Error {
     /// An error reported by the Nitrokey device in the response packet.
     CommandError(CommandError),
+    /// Placeholder for testing.
+    CommunicationError(CommunicationError),
 }
 
 impl From<CommandError> for Error {
@@ -21,6 +23,7 @@ impl error::Error for Error {
     fn source(&self) -> Option<&(dyn error::Error + 'static)> {
         match *self {
             Error::CommandError(ref err) => Some(err),
+            Error::CommunicationError(_) => None,
         }
     }
 }
@@ -29,6 +32,7 @@ impl fmt::Display for Error {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match *self {
             Error::CommandError(ref err) => write!(f, "Command error: {}", err),
+            Error::CommunicationError(_) => write!(f, "Placeholder"),
         }
     }
 }
@@ -78,6 +82,13 @@ pub enum CommandError {
     RngError,
 }
 
+/// Placeholder for testing.
+#[derive(Debug)]
+pub enum CommunicationError {
+    /// Placeholder for testing.
+    NotConnected,
+}
+
 impl CommandError {
     fn as_str(&self) -> borrow::Cow<'static, str> {
         match *self {