I remember the incredibly elegant AST-based diffing in Eclipse (which I haven't used in about 10 years; I can only assume it's still fantastic), which showed yo

I remember the incredibly elegant AST-based diffing in Eclipse (which I haven't used in about 10 years; I can only assume it's still fantastic), which showed you an outline of which classes, methods etc. have changed. AST-based diff naturally requires a parser for every language, and for some languages like C and C++ you need to bake preprocessor stuff (macros, ifdefs, includes etc.) into the node tree. But it's doable.