fix(createCollection): Db.createCollection should pass readConcern to new collection

lib/core/sessions.js

@@ -651,10 +651,10 @@ function applySession(session, command, options) {
       session.transaction.transition(TxnState.NO_TRANSACTION);
     }
 
-    // TODO: the following should only be applied to read operation per spec.
     // for causal consistency
     if (session.supports.causalConsistency && session.operationTime) {
       command.readConcern = command.readConcern || {};
+      console.log('this is the command!! : ', command);
       Object.assign(command.readConcern, { afterClusterTime: session.operationTime });
     }
 

lib/db.js

@@ -505,7 +505,9 @@ Db.prototype.createCollection = deprecateOptions(
     if (typeof options === 'function') (callback = options), (options = {});
     options = options || {};
     options.promiseLibrary = options.promiseLibrary || this.s.promiseLibrary;
-
+    options.readConcern = options.readConcern
+      ? new ReadConcern(options.readConcern.level)
+      : this.readConcern;
     const createCollectionOperation = new CreateCollectionOperation(this, name, options);
 
     return executeOperation(this.s.topology, createCollectionOperation, callback);

test/functional/readconcern_tests.js

@@ -37,6 +37,10 @@ describe('ReadConcern', function() {
         var collection = db.collection('readConcernCollection');
         // Validate readConcern
         test.deepEqual({ level: 'local' }, collection.s.readConcern);
+        // create a collection using createCollection
+        var createdCollection = db.createCollection('readConcernCollection');
+        // validate readConcern
+        test.deepEqual({ level: 'local' }, createdCollection.s.readConcern);
         // Perform a find using the readConcern
         listener.on('started', function(event) {
           if (event.commandName === 'find') started.push(event);

test/functional/view_tests.js

@@ -61,7 +61,8 @@ describe('Views', function() {
             expect(commandResult).to.eql({
               create: 'test',
               viewOn: 'users',
-              pipeline: [{ $match: {} }]
+              pipeline: [{ $match: {} }],
+              readConcern: {}
             });
 
             client.close();