Unity may have its detractors and genuine deficiencies but the Unity projects I worked on were much more maintainable due to the constraints of working inside Unity itself.
In what languages have you seen a big code base that you liked? Just curious.
As a game developer who mostly worked in Unity, this is horrifying. Unity-based projects are pile of horseshit in terms of architecture and organization, and I honestly hoped that AAA stuff is held to a higher standard.
It may have changed a bit now that hardware speed doesn't increase that much anymore, but historically, that even applied to game series. Even if you knew there would be a sequel, that sequel would target vastly improved hardware, which means new graphics effects, higher-resolution textures, etc.
That is not an environment that leads to high-quality code. The ability to update a game over the Internet hasn't improved that situation, to state it mildly.
I remember when we'd take UE3 drops, it's take one engineer a whole month of compiler errors + fixing stuff to get it back to where we started with.
https://cs.chromium.org/chromium/src/?sq=package:chromium&ty...
So, while these code bases are wonderfully informative and good to learn from in many ways, they won't teach you "modern" C++ styles. I put "modern" in quotes because there's nothing wrong with choosing a style that doesn't use the latest whiz-bang features.
It's a fine guide, but it was written for google and has some stuff in there as a result of that (no exceptions being on example).
While I can understand the ideas behind it, exceptions do cause head aches, I find it really weird. Enforcing this means using a very limited part of the C++ standard library, e.g. no std::vector, std::map, etc, because all those can throw exceptions. If you say no to exceptions but yes to std::vector then you either need to write code that works in the presence of exceptions (which means you could just say yes to them) or you have shoved your head in the sand like an ostrich thinking if you can't see them they can't happen.