test: add test to make sure only writeErrors key has validation settings toggled

Author: Grace Chong

src/cmap/commands.ts

@@ -838,6 +838,9 @@ export class BinMsg {
     const promoteValues = options.promoteValues ?? this.opts.promoteValues;
     const promoteBuffers = options.promoteBuffers ?? this.opts.promoteBuffers;
     const bsonRegExp = options.bsonRegExp ?? this.opts.bsonRegExp;
+    if (options.validation && Object.keys(options.validation.utf8)[0] !== 'writeErrors') {
+      throw new Error('Can only toggle validation settings for writeErrors key');
+    }
     const validation = options.validation ?? { utf8: { writeErrors: false } };
 
     // Set up the options

test/unit/commands.test.ts

@@ -71,6 +71,18 @@ const invalidUtf8InOtherKeyJSON = {
 };
 
 describe('BinMsg', function () {
+  it('should throw error if trying to toggle validation settings for keys other than writeErrors', function () {
+    const binMsgInvalidUtf8ErrorMsg = new BinMsg(
+      Buffer.alloc(0),
+      msgHeader,
+      msgBodyInvalidUtf8WriteErrors
+    );
+    expect(() => binMsgInvalidUtf8ErrorMsg.parse({ validation: { utf8: { n: false } } })).to.throw(
+      Error,
+      'Can only toggle validation settings for writeErrors key'
+    );
+  });
+
   it('should not throw invalid utf8 error when validation disabled for writeErrors', function () {
     const binMsgInvalidUtf8ErrorMsg = new BinMsg(
       Buffer.alloc(0),