wip, test: add tests for only-entity queries

db/src/engine.rs

@@ -57,9 +57,10 @@ pub fn execute(
                         && matches!(pattern.attribute, PatternQueryComponent::Discard)
                         && matches!(pattern.value, PatternQueryComponent::Discard) =>
                 {
-                    Ok(InnerQueryResult::Entities(
-                        entries.into_iter().map(|e| e.entity).collect(),
-                    ))
+                    let mut result: Vec<Vec<u8>> = entries.into_iter().map(|e| e.entity).collect();
+                    result.sort_unstable();
+                    result.dedup();
+                    Ok(InnerQueryResult::Entities(result))
                 }
                 QueryPart::Matches(pattern)
                     if matches!(pattern.entity, PatternQueryComponent::Discard)

db/src/lib.rs

@@ -547,6 +547,16 @@ mod test {
         let result = connection.query::<Vec<Entry>>(query).unwrap();
         assert_eq!(result.len(), 0);
 
+        // Test only-queries
+        let query = format!(r#"(matches ? ? ?)"#).parse().unwrap();
+        let result = connection.query::<Vec<Address>>(query).unwrap();
+        assert_eq!(result.len(), 2);
+
+        let query = format!(r#"(matches ? _ _)"#).parse().unwrap();
+        let result = connection.query::<Vec<Address>>(query).unwrap();
+        println!("{:?}", result);
+        assert_eq!(result.len(), 1);
+
         // Test IN queries for entities
         let other_entity = Address::Uuid(uuid::Uuid::new_v4());
         upend_insert_val!(connection, random_entity, ATTR_LABEL, "BAZQUX").unwrap();