Implement Error for Errors.

For Dispaly, it's not the prettiest output imaginable,
since it just contains error codes.

But it's still better than nothing.

1 files changed, 28 insertions, 1 deletions

diff --git a/validator/src/types.rs b/validator/src/types.rs
index 5b96cfe..0a7c2fa 100644
--- a/validator/src/types.rs
+++ b/validator/src/types.rs
@@ -1,6 +1,6 @@
+use std::{self, fmt};
 use std::collections::HashMap;
 
-
 #[derive(Debug)]
 pub struct Errors(HashMap<String, Vec<String>>);
 
@@ -22,6 +22,33 @@ impl Errors {
     }
 }
 
+impl fmt::Display for Errors {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        write!(fmt, "Validation failed:\n")?;
+        for (field, errs) in &self.0 {
+            write!(fmt, "    {}: [", field)?;
+
+            let last = errs.len() - 1;
+            for (index, err) in errs.iter().enumerate() {
+                write!(fmt, "{}", err)?;
+                if index < last { write!(fmt, ", ")? }
+            }
+            write!(fmt, "]\n")?;
+        }
+        Ok(())
+    }
+}
+
+impl std::error::Error for Errors {
+    fn description(&self) -> &str {
+        "validation failed"
+    }
+
+    fn cause(&self) -> Option<&std::error::Error> {
+        None
+    }
+}
+
 pub trait Validate {
     fn validate(&self) -> Result<(), Errors>;
 }