Vendor dependencies

notes-service/vendor/derive_builder/examples/validation.rs

@@ -0,0 +1,33 @@
+//! This example illustrates the use of `validate` to add a pre-build validation
+//! step.
+
+use derive_builder::Builder;
+
+#[derive(Builder, Debug, PartialEq)]
+#[builder(build_fn(validate = Self::validate))]
+struct Lorem {
+    pub ipsum: u8,
+}
+
+impl LoremBuilder {
+    /// Check that `Lorem` is putting in the right amount of effort.
+    fn validate(&self) -> Result<(), String> {
+        if let Some(ref ipsum) = self.ipsum {
+            match *ipsum {
+                i if i < 20 => Err("Try harder".to_string()),
+                i if i > 100 => Err("You'll tire yourself out".to_string()),
+                _ => Ok(()),
+            }
+        } else {
+            Ok(())
+        }
+    }
+}
+
+fn main() {
+    // If we're trying too hard...
+    let x = LoremBuilder::default().ipsum(120).build().unwrap_err();
+
+    // .. the build will fail:
+    assert_eq!(&x.to_string(), "You'll tire yourself out");
+}