PYTHON-2179 Raise client-side error if an index hint is specified for an unacknowledged operation

Author: prashantmital

pymongo/collection.py

@@ -2933,6 +2933,9 @@ def _find_and_modify(session, sock_info, retryable_write):
                 if sock_info.max_wire_version < 8:
                     raise ConfigurationError(
                         'Must be connected to MongoDB 4.2+ to use hint.')
+                if not write_concern.acknowledged:
+                    raise ConfigurationError(
+                        'hint is unsupported for unacknowledged writes.')
                 cmd['hint'] = hint
             if (sock_info.max_wire_version >= 4 and
                     not write_concern.is_server_default):

test/crud/v2/unacknowledged-bulkWrite-delete-hint-clientError.json

@@ -0,0 +1,155 @@
+{
+  "data": [
+    {
+      "_id": 1,
+      "x": 11
+    },
+    {
+      "_id": 2,
+      "x": 22
+    },
+    {
+      "_id": 3,
+      "x": 33
+    },
+    {
+      "_id": 4,
+      "x": 44
+    }
+  ],
+  "collection_name": "BulkWrite_delete_hint",
+  "tests": [
+    {
+      "description": "Unacknowledged bulkWrite deleteOne with hints fails with client-side error",
+      "operations": [
+        {
+          "name": "bulkWrite",
+          "collectionOptions": {
+            "writeConcern": {
+              "w": 0
+            }
+          },
+          "arguments": {
+            "requests": [
+              {
+                "name": "deleteOne",
+                "arguments": {
+                  "filter": {
+                    "_id": 1
+                  },
+                  "hint": "_id_"
+                }
+              },
+              {
+                "name": "deleteOne",
+                "arguments": {
+                  "filter": {
+                    "_id": 2
+                  },
+                  "hint": {
+                    "_id": 1
+                  }
+                }
+              }
+            ],
+            "options": {
+              "ordered": true
+            }
+          },
+          "error": true
+        }
+      ],
+      "expectations": [],
+      "outcome": {
+        "collection": {
+          "data": [
+            {
+              "_id": 1,
+              "x": 11
+            },
+            {
+              "_id": 2,
+              "x": 22
+            },
+            {
+              "_id": 3,
+              "x": 33
+            },
+            {
+              "_id": 4,
+              "x": 44
+            }
+          ]
+        }
+      }
+    },
+    {
+      "description": "Unacknowledged bulkWrite deleteMany with hints fails with client-side error",
+      "operations": [
+        {
+          "name": "bulkWrite",
+          "collectionOptions": {
+            "writeConcern": {
+              "w": 0
+            }
+          },
+          "arguments": {
+            "requests": [
+              {
+                "name": "deleteMany",
+                "arguments": {
+                  "filter": {
+                    "_id": {
+                      "$lt": 3
+                    }
+                  },
+                  "hint": "_id_"
+                }
+              },
+              {
+                "name": "deleteMany",
+                "arguments": {
+                  "filter": {
+                    "_id": {
+                      "$gte": 4
+                    }
+                  },
+                  "hint": {
+                    "_id": 1
+                  }
+                }
+              }
+            ],
+            "options": {
+              "ordered": true
+            }
+          },
+          "error": true
+        }
+      ],
+      "expectations": [],
+      "outcome": {
+        "collection": {
+          "data": [
+            {
+              "_id": 1,
+              "x": 11
+            },
+            {
+              "_id": 2,
+              "x": 22
+            },
+            {
+              "_id": 3,
+              "x": 33
+            },
+            {
+              "_id": 4,
+              "x": 44
+            }
+          ]
+        }
+      }
+    }
+  ]
+}