Autocomplete is the first step. Then you get linting, static analysis, autoformat on save, and code snippets. All built into your fancy IDE with plugins. You are super productive, you learn from its suggestions that you can quickly flip through, and your coworkers are happy that they only have to check your code for correctness and implementation, not style and edge cases.
If you're referring to formal verification tools (which help programmers mathematically prove that their program has certain properties). Then it doesn't need to extend into all the edge cases. Usually if the machine tells you it can't create a proof you add more checks to your code or pick the properties so that they're easy to prove. There's no need for completeness.
If you're referring to anything your parent mentioned, those tools already exist.
