Breeze.js: error when assigning compound foreign key with GUID and integer values

Question

I'm encountering an error with Breeze.js version 1.4.12. I have an entity, OrderLine, that has a compound primary key consisting of one GUID field (OrderId) and one integer field (LineNumber). This entity has a self-referencing foreign key, consisting of two fields: DependsOnOrderId and DependsOnLineNumber.

When creating a new instance of the OrderLine entity, and passing an object of initial values, I can assign values to the foreign key fields and everything works as expected. However, my issues lies when trying to assign values after entity creation. Assigning a value to the DependsOnOrderId property works correctly. When I assign a value to the DependsOnLineNumber property, I receive an error message: Type Error: undefined is not a function. This error occurs at line breeze.debug.js:4275 and a debugging session shows that it is trying to run a toLowerCase() method on the integer field value of the compound key.

The two lines that appear to be causing the issue are referenced below:

if (kp.dataType === DataType.Guid) {
    keyValues[i] && keyValues[i].toLowerCase();

I was able to resolve this issue satisfactorily by adjusting the lines to read:

if (kp.dataType === DataType.Guid) {
    keyValues[i] = keyValues[i] && ( ( keyValues[i].toLowerCase && keyValues[i].toLowerCase() ) || keyValues[i] );

This was only put together as a proof of concept to resolve the issue and has not been tested in all cases, but it ensures that when comparing a non-GUID value that is part of a GUID/non-GUID composite key, a toLowerCase() call is not attempted against a value that does not have that method.

Has anyone else encountered this error or have suggestions for fixing? I was thinking of putting together a pull request on GitHub, but wanted to check to see if there were other instances of this issue, or possible side effects with my suggested fix.

Thanks!

Answer 1

Your fix looks good, and I've added it to [email protected]

Thanks for your help on this. And sorry it took so long.