ref: Use different error message for empty strings in schema processing

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## Unreleased
+
+**Features**:
+
+- Use different error message for empty strings in schema processing. ([#2151](https://github.com/getsentry/relay/pull/2151))
+
 ## 23.5.1
 
 **Bug Fixes**:

relay-general/src/store/schema.rs

@@ -13,7 +13,7 @@ impl Processor for SchemaProcessor {
         state: &ProcessingState<'_>,
     ) -> ProcessingResult {
         value_trim_whitespace(value, meta, state);
-        verify_value_nonempty(value, meta, state)?;
+        verify_value_nonempty_string(value, meta, state)?;
         verify_value_characters(value, meta, state)?;
         Ok(())
     }
@@ -84,6 +84,22 @@ where
     }
 }
 
+fn verify_value_nonempty_string<T>(
+    value: &mut T,
+    meta: &mut Meta,
+    state: &ProcessingState<'_>,
+) -> ProcessingResult
+where
+    T: Empty,
+{
+    if state.attrs().nonempty && value.is_empty() {
+        meta.add_error(Error::nonempty_string());
+        Err(ProcessingAction::DeleteValueHard)
+    } else {
+        Ok(())
+    }
+}
+
 fn verify_value_characters(
     value: &mut str,
     meta: &mut Meta,
@@ -113,7 +129,7 @@ mod tests {
     };
     use crate::types::{Annotated, Array, Error, ErrorKind, Object};
 
-    fn assert_nonempty_base<T>()
+    fn assert_nonempty_base<T>(expected_error: &str)
     where
         T: Default + PartialEq + crate::processor::ProcessValue,
     {
@@ -133,25 +149,25 @@ mod tests {
         assert_eq!(
             wrapper,
             Annotated::new(Foo {
-                bar: Annotated::from_error(Error::expected("a non-empty value"), None),
+                bar: Annotated::from_error(Error::expected(expected_error), None),
                 bar2: Annotated::new(T::default())
             })
         );
     }
 
     #[test]
     fn test_nonempty_string() {
-        assert_nonempty_base::<String>();
+        assert_nonempty_base::<String>("a non-empty string");
     }
 
     #[test]
     fn test_nonempty_array() {
-        assert_nonempty_base::<Array<u64>>();
+        assert_nonempty_base::<Array<u64>>("a non-empty value");
     }
 
     #[test]
     fn test_nonempty_object() {
-        assert_nonempty_base::<Object<u64>>();
+        assert_nonempty_base::<Object<u64>>("a non-empty value");
     }
 
     #[test]

relay-general/src/types/meta.rs

@@ -314,6 +314,12 @@ impl Error {
         Error::invalid("expected a non-empty value")
     }
 
+    /// Creates an error that describes an expected non-empty string.
+    pub fn nonempty_string() -> Self {
+        // TODO: Replace `invalid_data` this with an explicity error constant for empty values
+        Error::invalid("expected a non-empty string")
+    }
+
     /// Returns the kind of this error.
     pub fn kind(&self) -> &ErrorKind {
         &self.kind