RUST-717 Send hint as part of deletes array in delete operation

Author: saghm

src/operation/delete/mod.rs

@@ -8,7 +8,7 @@ use crate::{
     collation::Collation,
     error::{convert_bulk_errors, Result},
     operation::{append_options, Operation, Retryability, WriteResponseBody},
-    options::{DeleteOptions, WriteConcern},
+    options::{DeleteOptions, Hint, WriteConcern},
     results::DeleteResult,
 };
 
@@ -19,6 +19,7 @@ pub(crate) struct Delete {
     limit: u32,
     options: Option<DeleteOptions>,
     collation: Option<Collation>,
+    hint: Option<Hint>,
 }
 
 impl Delete {
@@ -46,6 +47,7 @@ impl Delete {
             filter,
             limit: limit.unwrap_or(0), // 0 = no limit
             collation: options.as_mut().and_then(|opts| opts.collation.take()),
+            hint: options.as_mut().and_then(|opts| opts.hint.take()),
             options,
         }
     }
@@ -65,6 +67,10 @@ impl Operation for Delete {
             delete.insert("collation", bson::to_bson(&collation)?);
         }
 
+        if let Some(ref hint) = self.hint {
+            delete.insert("hint", bson::to_bson(&hint)?);
+        }
+
         let mut body = doc! {
             Self::NAME: self.ns.coll.clone(),
             "deletes": [delete],

src/test/coll.rs

@@ -611,12 +611,15 @@ async fn delete_hint_test(options: Option<DeleteOptions>, name: &str) {
     let events = client.get_command_started_events(&["delete"]);
     assert_eq!(events.len(), 1);
 
-    let event_hint = events[0].command.get("hint").cloned();
+    let event_hint = events[0].command.get_array("deletes").unwrap()[0]
+        .as_document()
+        .unwrap()
+        .get("hint");
     let expected_hint = match options {
         Some(options) => options.hint.map(|hint| hint.to_bson()),
         None => None,
     };
-    assert_eq!(event_hint, expected_hint);
+    assert_eq!(event_hint, expected_hint.as_ref());
 }
 
 #[cfg_attr(feature = "tokio-runtime", tokio::test)]