1 files changed, 59 insertions, 0 deletions
diff --git a/vendor/hex/src/error.rs b/vendor/hex/src/error.rs
new file mode 100644
index 000000000..ff7a3b5c1
--- /dev/null
+++ b/vendor/hex/src/error.rs
@@ -0,0 +1,59 @@
+use core::fmt;
+
+/// The error type for decoding a hex string into `Vec<u8>` or `[u8; N]`.
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub enum FromHexError {
+    /// An invalid character was found. Valid ones are: `0...9`, `a...f`
+    /// or `A...F`.
+    InvalidHexCharacter { c: char, index: usize },
+
+    /// A hex string's length needs to be even, as two digits correspond to
+    /// one byte.
+    OddLength,
+
+    /// If the hex string is decoded into a fixed sized container, such as an
+    /// array, the hex string's length * 2 has to match the container's
+    /// length.
+    InvalidStringLength,
+}
+
+#[cfg(feature = "std")]
+impl std::error::Error for FromHexError {}
+
+impl fmt::Display for FromHexError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match *self {
+            FromHexError::InvalidHexCharacter { c, index } => {
+                write!(f, "Invalid character {:?} at position {}", c, index)
+            }
+            FromHexError::OddLength => write!(f, "Odd number of digits"),
+            FromHexError::InvalidStringLength => write!(f, "Invalid string length"),
+        }
+    }
+}
+
+#[cfg(test)]
+// this feature flag is here to suppress unused
+// warnings of `super::*` and `pretty_assertions::assert_eq`
+#[cfg(feature = "alloc")]
+mod tests {
+    use super::*;
+    #[cfg(feature = "alloc")]
+    use alloc::string::ToString;
+    use pretty_assertions::assert_eq;
+
+    #[test]
+    #[cfg(feature = "alloc")]
+    fn test_display() {
+        assert_eq!(
+            FromHexError::InvalidHexCharacter { c: '\n', index: 5 }.to_string(),
+            "Invalid character '\\n' at position 5"
+        );
+
+        assert_eq!(FromHexError::OddLength.to_string(), "Odd number of digits");
+        assert_eq!(
+            FromHexError::InvalidStringLength.to_string(),
+            "Invalid string length"
+        );
+    }
+}