Merge pull request #217 from Lucretiel:error-traits

Add trait implementations to ParseQuantityError.

src/lib.rs

@@ -621,6 +621,8 @@ pub mod fmt {
 
 /// Unicode string slice manipulation for quantities.
 pub mod str {
+    use crate::lib::fmt::{self, Display, Formatter};
+
     /// Represents an error encountered while parsing a string into a `Quantity`.
     #[allow(missing_copy_implementations)]
     #[derive(Clone, Debug, Eq, PartialEq)]
@@ -641,4 +643,19 @@ pub mod str {
         /// unit name (description) is correct.
         UnknownUnit,
     }
+
+    impl Display for ParseQuantityError {
+        fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+            use ParseQuantityError::*;
+
+            match *self {
+                NoSeparator => write!(f, "no space between quantity and units"),
+                ValueParseError => write!(f, "error parsing unit quantity"),
+                UnknownUnit => write!(f, "unrecognized unit of measure"),
+            }
+        }
+    }
+
+    #[cfg(feature = "std")]
+    impl crate::lib::error::Error for ParseQuantityError {}
 }

src/tests/asserts.rs

@@ -17,6 +17,12 @@ assert_impl_all!(DisplayStyle:
 assert_not_impl_any!(DisplayStyle:
     Binary, Display, Eq, Hash, LowerExp, LowerHex, Ord, Octal, PartialEq, PartialOrd, UpperExp,
     UpperHex);
+#[rustfmt::skip]
+assert_impl_all!(ParseQuantityError:
+    Clone, Debug, Display, Eq, PartialEq, Send, Sync, Unpin);
+#[rustfmt::skip]
+assert_not_impl_any!(ParseQuantityError:
+    Binary, Copy, Hash, LowerExp, LowerHex, Ord, Octal, PartialOrd, UpperExp, UpperHex);
 
 storage_types! {
     types: Float;