fix: add test_keyword_presence() test

refactored/tests/test_in_memory.rs

@@ -818,3 +818,81 @@ async fn test_graph_compacting() {
         check_search_result(&res, &rob_keyword, &robert_doe_location);
     }
 }
+
+#[actix_rt::test]
+async fn test_keyword_presence() -> Result<(), Error<KvStoreError>> {
+    let mut indexed_value_to_keywords = HashMap::new();
+
+    // direct location robert doe
+    let robert_doe_location = Location::from("robert doe DB location");
+    indexed_value_to_keywords.insert(
+        IndexedValue::Data(robert_doe_location.clone()),
+        hashset_keywords(&["robert", "doe"]),
+    );
+
+    // direct location john doe
+    let john_doe_location = Location::from("john doe DB location");
+    indexed_value_to_keywords.insert(
+        IndexedValue::Data(john_doe_location.clone()),
+        hashset_keywords(&["john", "doe"]),
+    );
+
+    let mut findex = Findex::new(
+        EntryTable::setup(InMemoryEdx::setup()),
+        ChainTable::setup(InMemoryEdx::setup()),
+    );
+
+    let master_key = findex.keygen();
+    let label = Label::from("First label.");
+
+    let new_keywords = findex
+        .add(&master_key, &label, indexed_value_to_keywords)
+        .await?;
+
+    // the 3 keywords should not be present in the database
+    assert_eq!(new_keywords.len(), 3);
+    assert!(new_keywords.contains(&Keyword::from("robert")));
+    assert!(new_keywords.contains(&Keyword::from("doe")));
+    assert!(new_keywords.contains(&Keyword::from("john")));
+
+    // Now insert a Robert Smith
+    let mut indexed_value_to_keywords = HashMap::new();
+    let robert_smith_location = Location::from("robert smith DB location");
+    indexed_value_to_keywords.insert(
+        IndexedValue::Data(robert_smith_location),
+        hashset_keywords(&["robert", "smith"]),
+    );
+    let new_keywords = findex
+        .add(&master_key, &label, indexed_value_to_keywords)
+        .await?;
+    // robert should be present, but not smith
+    assert_eq!(new_keywords.len(), 1);
+    assert!(!new_keywords.contains(&Keyword::from("robert")));
+    assert!(new_keywords.contains(&Keyword::from("smith")));
+
+    // Delete Robert Smith and the junior keyword
+    let robert_smith_location = Location::from("robert smith DB location");
+    let mut indexed_value_to_keywords = HashMap::new();
+    indexed_value_to_keywords.insert(
+        IndexedValue::Data(robert_smith_location.clone()),
+        hashset_keywords(&["robert", "smith", "junior"]),
+    );
+    let new_keywords = findex
+        .delete(&master_key, &label, indexed_value_to_keywords.clone())
+        .await?;
+    // robert and smith should be present, but not junior
+    assert_eq!(new_keywords.len(), 1);
+    assert!(!new_keywords.contains(&Keyword::from("robert")));
+    assert!(!new_keywords.contains(&Keyword::from("smith")));
+    assert!(new_keywords.contains(&Keyword::from("junior")));
+
+    // however, the first delete create an entry for "junior,
+    // therefore deleting again will find it
+    let new_keywords = findex
+        .delete(&master_key, &label, indexed_value_to_keywords.clone())
+        .await?;
+    // all should be present
+    assert_eq!(new_keywords.len(), 0);
+
+    Ok(())
+}