feat: add the documents fields repartition into stats

meilidb-data/tests/updates.rs

@@ -1,3 +1,5 @@
+#[macro_use] extern crate maplit;
+
 use std::sync::atomic::{AtomicBool, Ordering::Relaxed};
 use std::sync::Arc;
 
@@ -94,3 +96,67 @@ fn replace_document() {
     assert_eq!(docs.len(), 1);
     assert_eq!(index.document(None, docs[0].id).unwrap().as_ref(), Some(&doc2));
 }
+
+#[test]
+fn database_stats() {
+    let tmp_dir = tempfile::tempdir().unwrap();
+    let database = Database::open(&tmp_dir).unwrap();
+
+    let as_been_updated = Arc::new(AtomicBool::new(false));
+
+    let schema = simple_schema();
+    let index = database.create_index("hello", schema).unwrap();
+
+    let as_been_updated_clone = as_been_updated.clone();
+    index.set_update_callback(move |_| as_been_updated_clone.store(true, Relaxed));
+
+    let doc1 = json!({ "objectId": 123, "title": "hello" });
+
+    let mut addition = index.documents_addition();
+    addition.update_document(&doc1);
+    let update_id = addition.finalize().unwrap();
+    let status = index.update_status_blocking(update_id).unwrap();
+    assert!(as_been_updated.swap(false, Relaxed));
+    assert!(status.result.is_ok());
+    let stats = index.stats().unwrap();
+    let repartition = hashmap!{
+        "objectId".to_string() => 1u64,
+        "title".to_string() => 1u64,
+    };
+    assert_eq!(stats.number_of_documents, 1);
+    assert_eq!(stats.documents_fields_repartition, repartition);
+
+    let doc2 = json!({ "objectId": 456, "title": "world" });
+
+    let mut addition = index.documents_addition();
+    addition.update_document(&doc2);
+    let update_id = addition.finalize().unwrap();
+    let status = index.update_status_blocking(update_id).unwrap();
+    assert!(as_been_updated.swap(false, Relaxed));
+    assert!(status.result.is_ok());
+    let stats = index.stats().unwrap();
+    let repartition = hashmap!{
+        "objectId".to_string() => 2u64,
+        "title".to_string() => 2u64,
+    };
+    assert_eq!(stats.number_of_documents, 2);
+    assert_eq!(stats.documents_fields_repartition, repartition);
+
+
+    let doc3 = json!({ "objectId": 789 });
+
+    let mut addition = index.documents_addition();
+    addition.update_document(&doc3);
+    let update_id = addition.finalize().unwrap();
+    let status = index.update_status_blocking(update_id).unwrap();
+    assert!(as_been_updated.swap(false, Relaxed));
+    assert!(status.result.is_ok());
+    let stats = index.stats().unwrap();
+    let repartition = hashmap!{
+        "objectId".to_string() => 3u64,
+        "title".to_string() => 2u64,
+    };
+    assert_eq!(stats.number_of_documents, 3);
+    assert_eq!(stats.documents_fields_repartition, repartition);
+
+}