Calling a prototype function straight after an object constructor doesn't work.

See the attached unit test, the following:
assertEquals(new Date().testProto(), 'prototype function works');

fails when it should work the same as:
var d = new Date();
assertEquals(d.testProto(), 'prototype function works');

which passes.

Debug log displays:
WARNING: testPrototype.lzx:29: reference to undefined property 'testProto'
ERROR: Compiler.substitute:-1: undefined object does not have a property 'make'
ERROR: Equals: expected «undefined» got 'prototype function works'

Unit test result displays:
Tests: 3 Failures: 1 Errors: 2
TestFailure: testNoVars failed: Equals: expected «undefined» got 'prototype function works'
TestError: testNoVars failed: undefined object does not have a property 'make'
TestError: testNoVars failed: reference to undefined property 'testProto'

The workaround is to assign the object to a var before using it, but this can really be used in a constraint.