It's not the cable that's the problem here; it's the device you're plugging into the cable.
You don't need a cable tester to detect this problem; just plug the device into a spec-compliant USB-C power brick with a USB-C cable and see if it fails to charge.
Comments
Wonder if there are USB C cable testers that detects this.
In practice, most if not all networking/hardware department carries a ethernet cable tester but somehow not true for USB cables.
It's not the cable that's the problem here; it's the device you're plugging into the cable.
You don't need a cable tester to detect this problem; just plug the device into a spec-compliant USB-C power brick with a USB-C cable and see if it fails to charge.
You don't need a tester to detect this (and it's not about cables).