rust/rhg/src/error.rs

--- a/rust/rhg/src/error.rs	Mon Jul 06 22:02:50 2020 -0400
+++ b/rust/rhg/src/error.rs	Fri Jun 05 09:01:35 2020 +0200
@@ -1,3 +1,60 @@
+use crate::exitcode;
+use crate::ui::UiError;
+use std::convert::From;
+
+/// The kind of command error
+#[derive(Debug, PartialEq)]
+pub enum CommandErrorKind {
+    /// The command finished without error
+    Ok,
+    /// The root of the repository cannot be found
+    RootNotFound,
+    /// The current directory cannot be found
+    CurrentDirNotFound,
+    /// The standard output stream cannot be written to
+    StdoutError,
+    /// The standard error stream cannot be written to
+    StderrError,
+}
+
+impl CommandErrorKind {
+    pub fn get_exit_code(&self) -> exitcode::ExitCode {
+        match self {
+            CommandErrorKind::Ok => exitcode::OK,
+            CommandErrorKind::RootNotFound => exitcode::ABORT,
+            CommandErrorKind::CurrentDirNotFound => exitcode::ABORT,
+            CommandErrorKind::StdoutError => exitcode::ABORT,
+            CommandErrorKind::StderrError => exitcode::ABORT,
+        }
+    }
+}
+
 /// The error type for the Command trait
 #[derive(Debug, PartialEq)]
-pub struct CommandError {}
+pub struct CommandError {
+    pub kind: CommandErrorKind,
+}
+
+impl CommandError {
+    /// Exist the process with the corresponding exit code.
+    pub fn exit(&self) -> () {
+        std::process::exit(self.kind.get_exit_code())
+    }
+}
+
+impl From<CommandErrorKind> for CommandError {
+    fn from(kind: CommandErrorKind) -> Self {
+        CommandError { kind }
+    }
+}
+
+impl From<UiError> for CommandError {
+    fn from(error: UiError) -> Self {
+        CommandError {
+            kind: match error {
+                UiError::StdoutError(_) => CommandErrorKind::StdoutError,
+                UiError::StderrError(_) => CommandErrorKind::StderrError,
+            },
+        }
+    }
+}