Introduce a clear all documents update

meilidb-core/src/store/docs_words.rs

@@ -26,6 +26,10 @@ impl DocsWords {
         self.docs_words.delete(writer, &document_id)
     }
 
+    pub fn clear(self, writer: &mut heed::RwTxn) -> ZResult<()> {
+        self.docs_words.clear(writer)
+    }
+
     pub fn doc_words(
         self,
         reader: &heed::RoTxn,

meilidb-core/src/store/documents_fields.rs

@@ -32,6 +32,10 @@ impl DocumentsFields {
         self.documents_fields.delete_range(writer, start..=end)
     }
 
+    pub fn clear(self, writer: &mut heed::RwTxn) -> ZResult<()> {
+        self.documents_fields.clear(writer)
+    }
+
     pub fn document_attribute<'txn>(
         self,
         reader: &'txn heed::RoTxn,

meilidb-core/src/store/documents_fields_counts.rs

@@ -32,6 +32,10 @@ impl DocumentsFieldsCounts {
             .delete_range(writer, start..=end)
     }
 
+    pub fn clear(self, writer: &mut heed::RwTxn) -> ZResult<()> {
+        self.documents_fields_counts.clear(writer)
+    }
+
     pub fn document_field_count(
         self,
         reader: &heed::RoTxn,

meilidb-core/src/store/mod.rs

@@ -166,6 +166,10 @@ impl Index {
         )
     }
 
+    pub fn clear_all(&self, writer: &mut heed::RwTxn) -> MResult<u64> {
+        update::push_clear_all(writer, self.updates, self.updates_results)
+    }
+
     pub fn synonyms_addition(&self) -> update::SynonymsAddition {
         update::SynonymsAddition::new(
             self.updates,