This reminds me of a project I was exposed to at school[1]
It allows you to search for code by the test cases it passes. It was a little slow, but that was one of the first times computers truly felt magical to me.
Quote from the linked article:
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The system works by using the keywords to access one of the available code search engines (or a local code search engine for code available at Brown), to get candidate files. Each class or method in these files (depending on what the user is searching for) is considered a potential solution. These solutions are then transformed using a set of about 30 transformations in an attempt to map the code into exactly what the programmer specified. The transformations range from the simple (e.g. changing the name of the method to match the signature) to the complex (e.g. finding a line in the method that computes a value of the returned type and then doing a backward slice until the only free variables are values of the parameter types). All the solutions that can be transformed to match the signature are then tested using the given test cases, security constraints, and JML rules.
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