Refactor io::Error into custom Error enum

1 files changed, 54 insertions, 1 deletions

diff --git a/src/lib.rs b/src/lib.rs
index b51a3cc..422252b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -79,7 +79,60 @@
 /// [`Backend`]: trait.Backend.html
 pub mod backends;
 
-use std::io::Result;
+use std::io;
+use std::process;
+use std::result;
+use std::str;
+use std::string;
+
+/// A result returned by `dialog`.
+pub type Result<T> = result::Result<T, Error>;
+
+/// An error returned by `dialog`.
+#[derive(Debug)]
+pub enum Error {
+    /// A general error with an error message.
+    Error(String),
+    /// An input or output error.
+    IoError(io::Error),
+    /// An UTF-8 error.
+    Utf8Error(str::Utf8Error),
+}
+
+impl From<&str> for Error {
+    fn from(string: &str) -> Error {
+        Error::Error(string.to_string())
+    }
+}
+
+impl From<io::Error> for Error {
+    fn from(error: io::Error) -> Error {
+        Error::IoError(error)
+    }
+}
+
+impl From<str::Utf8Error> for Error {
+    fn from(error: str::Utf8Error) -> Error {
+        Error::Utf8Error(error)
+    }
+}
+
+impl From<string::FromUtf8Error> for Error {
+    fn from(error: string::FromUtf8Error) -> Error {
+        Error::Utf8Error(error.utf8_error())
+    }
+}
+
+impl From<(&str, process::ExitStatus)> for Error {
+    fn from(data: (&str, process::ExitStatus)) -> Error {
+        let (command, status) = data;
+        let msg = match status.code() {
+            Some(code) => format!("Command {} failed with exit status {}", command, code),
+            None => format!("Command {} was terminated by a signal", command),
+        };
+        Error::Error(msg)
+    }
+}
 
 /// A dialog box that can be shown using a backend.
 ///