fix(NODE-6420): support options for aggregationcursor/findcursor.explain() (#52)

Author: baileympearson

.eslintrc.json

@@ -9,8 +9,14 @@
     "node": true,
     "es6": true
   },
-  "plugins": ["prettier", "@typescript-eslint"],
-  "extends": ["eslint:recommended", "plugin:prettier/recommended"],
+  "plugins": [
+    "prettier",
+    "@typescript-eslint"
+  ],
+  "extends": [
+    "eslint:recommended",
+    "plugin:prettier/recommended"
+  ],
   "rules": {
     "strict": "error",
     "prettier/prettier": "error",
@@ -24,6 +30,9 @@
       }
     ],
     "no-implicit-coercion": "error",
-    "@typescript-eslint/strict-boolean-expressions": "error"
+    "@typescript-eslint/strict-boolean-expressions": "error",
+    "no-unused-vars": ["error", {
+      "argsIgnorePattern": "^_"
+    }]
   }
-}
+}

src/legacy_wrappers/cursors.js

@@ -25,15 +25,18 @@ module.exports.makeLegacyFindCursor = function (baseClass) {
       return maybeCallback(super.count(options), callback);
     }
 
-    explain(verbosity, callback) {
+    explain(verbosity, options, callback) {
       callback =
         typeof callback === 'function'
           ? callback
-          : typeof verbosity === 'function'
-            ? verbosity
-            : undefined;
+          : typeof options === 'function'
+            ? options
+            : typeof verbosity === 'function'
+              ? verbosity
+              : undefined;
+      options = typeof options !== 'function' ? options : undefined;
       verbosity = typeof verbosity !== 'function' ? verbosity : undefined;
-      return maybeCallback(super.explain(verbosity), callback);
+      return maybeCallback(super.explain(verbosity, options), callback);
     }
 
     close(options, callback) {
@@ -180,15 +183,18 @@ module.exports.makeLegacyAggregationCursor = function (baseClass) {
   }
 
   class LegacyAggregationCursor extends baseClass {
-    explain(verbosity, callback) {
+    explain(verbosity, options, callback) {
       callback =
         typeof callback === 'function'
           ? callback
-          : typeof verbosity === 'function'
-            ? verbosity
-            : undefined;
+          : typeof options === 'function'
+            ? options
+            : typeof verbosity === 'function'
+              ? verbosity
+              : undefined;
+      options = typeof options !== 'function' ? options : undefined;
       verbosity = typeof verbosity !== 'function' ? verbosity : undefined;
-      return maybeCallback(super.explain(verbosity), callback);
+      return maybeCallback(super.explain(verbosity, options), callback);
     }
 
     close(options, callback) {

test/tools/api.js

@@ -38,7 +38,7 @@ const api = [
   { className: 'Admin', method: 'serverStatus', returnType: 'Promise<Document>' },
   { className: 'Admin', method: 'validateCollection', returnType: 'Promise<Document>' },
 
-  { className: 'AggregationCursor', method: 'explain', returnType: 'Promise<Document>' },
+  { className: 'AggregationCursor', method: 'explain', returnType: 'Promise<Document>', possibleCallbackPositions: [1, 2, 3] },
   { className: 'AggregationCursor', method: 'clone', returnType: 'AggregationCursor', notAsync: true },
 
   { className: 'FindCursor', method: 'clone', returnType: 'FindCursor', notAsync: true },
@@ -115,7 +115,7 @@ const api = [
   { className: 'Db', method: 'watch', returnType: 'ChangeStream', notAsync: true },
 
   { className: 'FindCursor', method: 'count', returnType: 'Promise<number>' },
-  { className: 'FindCursor', method: 'explain', returnType: 'Promise<Document>' },
+  { className: 'FindCursor', method: 'explain', returnType: 'Promise<Document>', possibleCallbackPositions: [1,2,3] },
 
   { className: 'GridFSBucket', method: 'delete', returnType: 'Promise<void>', possibleCallbackPositions: [1, 2] },
   { className: 'GridFSBucket', method: 'drop', returnType: 'Promise<void>', possibleCallbackPositions: [1, 2] },