1 files changed, 37 insertions, 0 deletions
diff --git a/vendor/derive_builder/src/error.rs b/vendor/derive_builder/src/error.rs
new file mode 100644
index 000000000..3e1fb4eba
--- /dev/null
+++ b/vendor/derive_builder/src/error.rs
@@ -0,0 +1,37 @@
+#[cfg(feature = "std")]
+use std::{error::Error, fmt};
+
+#[cfg(not(feature = "std"))]
+use core::fmt;
+
+/// Runtime error when a `build()` method is called and one or more required fields
+/// do not have a value.
+#[derive(Debug, Clone)]
+pub struct UninitializedFieldError(&'static str);
+
+impl UninitializedFieldError {
+    /// Create a new `UnitializedFieldError` for the specified field name.
+    pub fn new(field_name: &'static str) -> Self {
+        UninitializedFieldError(field_name)
+    }
+
+    /// Get the name of the first-declared field that wasn't initialized
+    pub fn field_name(&self) -> &'static str {
+        self.0
+    }
+}
+
+impl fmt::Display for UninitializedFieldError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "Field not initialized: {}", self.0)
+    }
+}
+
+#[cfg(feature = "std")]
+impl Error for UninitializedFieldError {}
+
+impl From<&'static str> for UninitializedFieldError {
+    fn from(field_name: &'static str) -> Self {
+        Self::new(field_name)
+    }
+}